Use a read-only snapshot transaction for calculating sync responses (#236)

* Use a read-only snapshot transaction for calculating sync responses

* gb vendor update github.com/lib/pq

src/github.com/matrix-org/dendrite/syncapi/storage/syncserver.go

@@ -187,18 +187,24 @@ func (d *SyncServerDatabase) IncrementalSync(
 	userID string,
 	fromPos, toPos types.StreamPosition,
 	numRecentEventsPerRoom int,
-) (res *types.Response, returnErr error) {
+) (*types.Response, error) {
-	returnErr = common.WithTransaction(d.db, func(txn *sql.Tx) error {
+	txn, err := d.db.BeginTx(ctx, &txReadOnlySnapshot)
+	if err != nil {
+		return nil, err
+	}
+	var succeeded bool
+	defer common.EndTransaction(txn, &succeeded)
+
 	// Work out which rooms to return in the response. This is done by getting not only the currently
 	// joined rooms, but also which rooms have membership transitions for this user between the 2 stream positions.
 	// This works out what the 'state' key should be for each room as well as which membership block
 	// to put the room into.
 	deltas, err := d.getStateDeltas(ctx, txn, fromPos, toPos, userID)
 	if err != nil {
-			return err
+		return nil, err
 	}
 
-		res = types.NewResponse(toPos)
+	res := types.NewResponse(toPos)
 	for _, delta := range deltas {
 		endPos := toPos
 		if delta.membershipPos > 0 && delta.membership == "leave" {
@@ -210,11 +216,12 @@ func (d *SyncServerDatabase) IncrementalSync(
 			// This is all "okay" assuming history_visibility == "shared" which it is by default.
 			endPos = delta.membershipPos
 		}
-			recentStreamEvents, err := d.events.selectRecentEvents(
+		var recentStreamEvents []streamEvent
+		recentStreamEvents, err = d.events.selectRecentEvents(
 			ctx, txn, delta.roomID, fromPos, endPos, numRecentEventsPerRoom,
 		)
 		if err != nil {
-				return err
+			return nil, err
 		}
 		recentEvents := streamEventsToEvents(recentStreamEvents)
 		delta.stateEvents = removeDuplicates(delta.stateEvents, recentEvents) // roll back
@@ -240,47 +247,58 @@ func (d *SyncServerDatabase) IncrementalSync(
 	}
 
 	// TODO: This should be done in getStateDeltas
-		return d.addInvitesToResponse(ctx, txn, userID, res)
+	if err = d.addInvitesToResponse(ctx, txn, userID, res); err != nil {
-	})
+		return nil, err
-	return
+	}
+
+	succeeded = true
+	return res, nil
 }
 
 // CompleteSync a complete /sync API response for the given user.
 func (d *SyncServerDatabase) CompleteSync(
 	ctx context.Context, userID string, numRecentEventsPerRoom int,
-) (res *types.Response, returnErr error) {
+) (*types.Response, error) {
 	// This needs to be all done in a transaction as we need to do multiple SELECTs, and we need to have
 	// a consistent view of the database throughout. This includes extracting the sync stream position.
 	// This does have the unfortunate side-effect that all the matrixy logic resides in this function,
 	// but it's better to not hide the fact that this is being done in a transaction.
-	returnErr = common.WithTransaction(d.db, func(txn *sql.Tx) error {
+	txn, err := d.db.BeginTx(ctx, &txReadOnlySnapshot)
+	if err != nil {
+		return nil, err
+	}
+	var succeeded bool
+	defer common.EndTransaction(txn, &succeeded)
+
 	// Get the current stream position which we will base the sync response on.
 	id, err := d.events.selectMaxID(ctx, txn)
 	if err != nil {
-			return err
+		return nil, err
 	}
 	pos := types.StreamPosition(id)
 
 	// Extract room state and recent events for all rooms the user is joined to.
 	roomIDs, err := d.roomstate.selectRoomIDsWithMembership(ctx, txn, userID, "join")
 	if err != nil {
-			return err
+		return nil, err
 	}
 
 	// Build up a /sync response. Add joined rooms.
-		res = types.NewResponse(pos)
+	res := types.NewResponse(pos)
 	for _, roomID := range roomIDs {
-			stateEvents, err := d.roomstate.selectCurrentState(ctx, txn, roomID)
+		var stateEvents []gomatrixserverlib.Event
+		stateEvents, err = d.roomstate.selectCurrentState(ctx, txn, roomID)
 		if err != nil {
-				return err
+			return nil, err
 		}
 		// TODO: When filters are added, we may need to call this multiple times to get enough events.
 		//       See: https://github.com/matrix-org/synapse/blob/v0.19.3/synapse/handlers/sync.py#L316
-			recentStreamEvents, err := d.events.selectRecentEvents(
+		var recentStreamEvents []streamEvent
+		recentStreamEvents, err = d.events.selectRecentEvents(
 			ctx, txn, roomID, types.StreamPosition(0), pos, numRecentEventsPerRoom,
 		)
 		if err != nil {
-				return err
+			return nil, err
 		}
 		recentEvents := streamEventsToEvents(recentStreamEvents)
 
@@ -292,9 +310,22 @@ func (d *SyncServerDatabase) CompleteSync(
 		res.Rooms.Join[roomID] = *jr
 	}
 
-		return d.addInvitesToResponse(ctx, txn, userID, res)
+	if err = d.addInvitesToResponse(ctx, txn, userID, res); err != nil {
-	})
+		return nil, err
-	return
+	}
+
+	succeeded = true
+	return res, err
+}
+
+var txReadOnlySnapshot = sql.TxOptions{
+	// Set the isolation level so that we see a snapshot of the database.
+	// In PostgreSQL repeatable read transactions will see a snapshot taken
+	// at the first query, and since the transaction is read-only it can't
+	// run into any serialisation errors.
+	// https://www.postgresql.org/docs/9.5/static/transaction-iso.html#XACT-REPEATABLE-READ
+	Isolation: sql.LevelRepeatableRead,
+	ReadOnly:  true,
 }
 
 // GetAccountDataInRange returns all account data for a given user inserted or

vendor/manifest

@@ -98,7 +98,7 @@
 		{
 			"importpath": "github.com/lib/pq",
 			"repository": "https://github.com/lib/pq",
-			"revision": "a6657b2386e9b8be76484c08711b02c7cf867ead",
+			"revision": "23da1db4f16d9658a86ae9b717c245fc078f10f1",
 			"branch": "master"
 		},
 		{

vendor/src/github.com/lib/pq/README.md

@@ -1,6 +1,6 @@
 # pq - A pure Go postgres driver for Go's database/sql package
 
-[![Build Status](https://travis-ci.org/lib/pq.png?branch=master)](https://travis-ci.org/lib/pq)
+[![Build Status](https://travis-ci.org/lib/pq.svg?branch=master)](https://travis-ci.org/lib/pq)
 
 ## Install
 

vendor/src/github.com/lib/pq/array.go

@@ -13,7 +13,7 @@ import (
 
 var typeByteSlice = reflect.TypeOf([]byte{})
 var typeDriverValuer = reflect.TypeOf((*driver.Valuer)(nil)).Elem()
-var typeSqlScanner = reflect.TypeOf((*sql.Scanner)(nil)).Elem()
+var typeSQLScanner = reflect.TypeOf((*sql.Scanner)(nil)).Elem()
 
 // Array returns the optimal driver.Valuer and sql.Scanner for an array or
 // slice of any dimension.
@@ -278,7 +278,7 @@ func (GenericArray) evaluateDestination(rt reflect.Type) (reflect.Type, func([]b
 	// TODO calculate the assign function for other types
 	// TODO repeat this section on the element type of arrays or slices (multidimensional)
 	{
-		if reflect.PtrTo(rt).Implements(typeSqlScanner) {
+		if reflect.PtrTo(rt).Implements(typeSQLScanner) {
 			// dest is always addressable because it is an element of a slice.
 			assign = func(src []byte, dest reflect.Value) (err error) {
 				ss := dest.Addr().Interface().(sql.Scanner)
@@ -587,7 +587,7 @@ func appendArrayElement(b []byte, rv reflect.Value) ([]byte, string, error) {
 		}
 	}
 
-	var del string = ","
+	var del = ","
 	var err error
 	var iv interface{} = rv.Interface()
 

vendor/src/github.com/lib/pq/conn.go

@@ -27,22 +27,22 @@ var (
 	ErrNotSupported              = errors.New("pq: Unsupported command")
 	ErrInFailedTransaction       = errors.New("pq: Could not complete operation in a failed transaction")
 	ErrSSLNotSupported           = errors.New("pq: SSL is not enabled on the server")
-	ErrSSLKeyHasWorldPermissions = errors.New("pq: Private key file has group or world access. Permissions should be u=rw (0600) or less.")
+	ErrSSLKeyHasWorldPermissions = errors.New("pq: Private key file has group or world access. Permissions should be u=rw (0600) or less")
-	ErrCouldNotDetectUsername    = errors.New("pq: Could not detect default username. Please provide one explicitly.")
+	ErrCouldNotDetectUsername    = errors.New("pq: Could not detect default username. Please provide one explicitly")
 
 	errUnexpectedReady = errors.New("unexpected ReadyForQuery")
 	errNoRowsAffected  = errors.New("no RowsAffected available after the empty statement")
-	errNoLastInsertId  = errors.New("no LastInsertId available after the empty statement")
+	errNoLastInsertID  = errors.New("no LastInsertId available after the empty statement")
 )
 
-type drv struct{}
+type Driver struct{}
 
-func (d *drv) Open(name string) (driver.Conn, error) {
+func (d *Driver) Open(name string) (driver.Conn, error) {
 	return Open(name)
 }
 
 func init() {
-	sql.Register("postgres", &drv{})
+	sql.Register("postgres", &Driver{})
 }
 
 type parameterStatus struct {
@@ -98,7 +98,7 @@ type conn struct {
 	namei     int
 	scratch   [512]byte
 	txnStatus transactionStatus
-	txnClosed chan<- struct{}
+	txnFinish func()
 
 	// Save connection arguments to use during CancelRequest.
 	dialer Dialer
@@ -131,9 +131,9 @@ type conn struct {
 }
 
 // Handle driver-side settings in parsed connection string.
-func (c *conn) handleDriverSettings(o values) (err error) {
+func (cn *conn) handleDriverSettings(o values) (err error) {
 	boolSetting := func(key string, val *bool) error {
-		if value := o.Get(key); value != "" {
+		if value, ok := o[key]; ok {
 			if value == "yes" {
 				*val = true
 			} else if value == "no" {
@@ -145,21 +145,20 @@ func (c *conn) handleDriverSettings(o values) (err error) {
 		return nil
 	}
 
-	err = boolSetting("disable_prepared_binary_result", &c.disablePreparedBinaryResult)
+	err = boolSetting("disable_prepared_binary_result", &cn.disablePreparedBinaryResult)
 	if err != nil {
 		return err
 	}
-	err = boolSetting("binary_parameters", &c.binaryParameters)
+	err = boolSetting("binary_parameters", &cn.binaryParameters)
 	if err != nil {
 		return err
 	}
 	return nil
 }
 
-func (c *conn) handlePgpass(o values) {
+func (cn *conn) handlePgpass(o values) {
 	// if a password was supplied, do not process .pgpass
-	_, ok := o["password"]
+	if _, ok := o["password"]; ok {
-	if ok {
 		return
 	}
 	filename := os.Getenv("PGPASSFILE")
@@ -187,11 +186,11 @@ func (c *conn) handlePgpass(o values) {
 	}
 	defer file.Close()
 	scanner := bufio.NewScanner(io.Reader(file))
-	hostname := o.Get("host")
+	hostname := o["host"]
 	ntw, _ := network(o)
-	port := o.Get("port")
+	port := o["port"]
-	db := o.Get("dbname")
+	db := o["dbname"]
-	username := o.Get("user")
+	username := o["user"]
 	// From: https://github.com/tg/pgpass/blob/master/reader.go
 	getFields := func(s string) []string {
 		fs := make([]string, 0, 5)
@@ -230,10 +229,10 @@ func (c *conn) handlePgpass(o values) {
 	}
 }
 
-func (c *conn) writeBuf(b byte) *writeBuf {
+func (cn *conn) writeBuf(b byte) *writeBuf {
-	c.scratch[0] = b
+	cn.scratch[0] = b
 	return &writeBuf{
-		buf: c.scratch[:5],
+		buf: cn.scratch[:5],
 		pos: 1,
 	}
 }
@@ -256,13 +255,13 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	// * Very low precedence defaults applied in every situation
 	// * Environment variables
 	// * Explicitly passed connection information
-	o.Set("host", "localhost")
+	o["host"] = "localhost"
-	o.Set("port", "5432")
+	o["port"] = "5432"
 	// N.B.: Extra float digits should be set to 3, but that breaks
 	// Postgres 8.4 and older, where the max is 2.
-	o.Set("extra_float_digits", "2")
+	o["extra_float_digits"] = "2"
 	for k, v := range parseEnviron(os.Environ()) {
-		o.Set(k, v)
+		o[k] = v
 	}
 
 	if strings.HasPrefix(name, "postgres://") || strings.HasPrefix(name, "postgresql://") {
@@ -277,9 +276,9 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	}
 
 	// Use the "fallback" application name if necessary
-	if fallback := o.Get("fallback_application_name"); fallback != "" {
+	if fallback, ok := o["fallback_application_name"]; ok {
-		if !o.Isset("application_name") {
+		if _, ok := o["application_name"]; !ok {
-			o.Set("application_name", fallback)
+			o["application_name"] = fallback
 		}
 	}
 
@@ -290,30 +289,29 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	// parsing its value is not worth it.  Instead, we always explicitly send
 	// client_encoding as a separate run-time parameter, which should override
 	// anything set in options.
-	if enc := o.Get("client_encoding"); enc != "" && !isUTF8(enc) {
+	if enc, ok := o["client_encoding"]; ok && !isUTF8(enc) {
 		return nil, errors.New("client_encoding must be absent or 'UTF8'")
 	}
-	o.Set("client_encoding", "UTF8")
+	o["client_encoding"] = "UTF8"
 	// DateStyle needs a similar treatment.
-	if datestyle := o.Get("datestyle"); datestyle != "" {
+	if datestyle, ok := o["datestyle"]; ok {
 		if datestyle != "ISO, MDY" {
 			panic(fmt.Sprintf("setting datestyle must be absent or %v; got %v",
 				"ISO, MDY", datestyle))
 		}
 	} else {
-		o.Set("datestyle", "ISO, MDY")
+		o["datestyle"] = "ISO, MDY"
 	}
 
 	// If a user is not provided by any other means, the last
 	// resort is to use the current operating system provided user
 	// name.
-	if o.Get("user") == "" {
+	if _, ok := o["user"]; !ok {
 		u, err := userCurrent()
 		if err != nil {
 			return nil, err
-		} else {
-			o.Set("user", u)
 		}
+		o["user"] = u
 	}
 
 	cn := &conn{
@@ -335,7 +333,7 @@ func DialOpen(d Dialer, name string) (_ driver.Conn, err error) {
 	cn.startup(o)
 
 	// reset the deadline, in case one was set (see dial)
-	if timeout := o.Get("connect_timeout"); timeout != "" && timeout != "0" {
+	if timeout, ok := o["connect_timeout"]; ok && timeout != "0" {
 		err = cn.c.SetDeadline(time.Time{})
 	}
 	return cn, err
@@ -349,7 +347,7 @@ func dial(d Dialer, o values) (net.Conn, error) {
 	}
 
 	// Zero or not specified means wait indefinitely.
-	if timeout := o.Get("connect_timeout"); timeout != "" && timeout != "0" {
+	if timeout, ok := o["connect_timeout"]; ok && timeout != "0" {
 		seconds, err := strconv.ParseInt(timeout, 10, 0)
 		if err != nil {
 			return nil, fmt.Errorf("invalid value for parameter connect_timeout: %s", err)
@@ -371,31 +369,18 @@ func dial(d Dialer, o values) (net.Conn, error) {
 }
 
 func network(o values) (string, string) {
-	host := o.Get("host")
+	host := o["host"]
 
 	if strings.HasPrefix(host, "/") {
-		sockPath := path.Join(host, ".s.PGSQL."+o.Get("port"))
+		sockPath := path.Join(host, ".s.PGSQL."+o["port"])
 		return "unix", sockPath
 	}
 
-	return "tcp", net.JoinHostPort(host, o.Get("port"))
+	return "tcp", net.JoinHostPort(host, o["port"])
 }
 
 type values map[string]string
 
-func (vs values) Set(k, v string) {
-	vs[k] = v
-}
-
-func (vs values) Get(k string) (v string) {
-	return vs[k]
-}
-
-func (vs values) Isset(k string) bool {
-	_, ok := vs[k]
-	return ok
-}
-
 // scanner implements a tokenizer for libpq-style option strings.
 type scanner struct {
 	s []rune
@@ -466,7 +451,7 @@ func parseOpts(name string, o values) error {
 		// Skip any whitespace after the =
 		if r, ok = s.SkipSpaces(); !ok {
 			// If we reach the end here, the last value is just an empty string as per libpq.
-			o.Set(string(keyRunes), "")
+			o[string(keyRunes)] = ""
 			break
 		}
 
@@ -501,7 +486,7 @@ func parseOpts(name string, o values) error {
 			}
 		}
 
-		o.Set(string(keyRunes), string(valRunes))
+		o[string(keyRunes)] = string(valRunes)
 	}
 
 	return nil
@@ -520,13 +505,17 @@ func (cn *conn) checkIsInTransaction(intxn bool) {
 }
 
 func (cn *conn) Begin() (_ driver.Tx, err error) {
+	return cn.begin("")
+}
+
+func (cn *conn) begin(mode string) (_ driver.Tx, err error) {
 	if cn.bad {
 		return nil, driver.ErrBadConn
 	}
 	defer cn.errRecover(&err)
 
 	cn.checkIsInTransaction(false)
-	_, commandTag, err := cn.simpleExec("BEGIN")
+	_, commandTag, err := cn.simpleExec("BEGIN" + mode)
 	if err != nil {
 		return nil, err
 	}
@@ -542,9 +531,8 @@ func (cn *conn) Begin() (_ driver.Tx, err error) {
 }
 
 func (cn *conn) closeTxn() {
-	if cn.txnClosed != nil {
+	if finish := cn.txnFinish; finish != nil {
-		close(cn.txnClosed)
+		finish()
-		cn.txnClosed = nil
 	}
 }
 
@@ -665,6 +653,12 @@ func (cn *conn) simpleQuery(q string) (res *rows, err error) {
 					cn: cn,
 				}
 			}
+			// Set the result and tag to the last command complete if there wasn't a
+			// query already run. Although queries usually return from here and cede
+			// control to Next, a query with zero results does not.
+			if t == 'C' && res.colNames == nil {
+				res.result, res.tag = cn.parseComplete(r.string())
+			}
 			res.done = true
 		case 'Z':
 			cn.processReadyForQuery(r)
@@ -703,7 +697,7 @@ var emptyRows noRows
 var _ driver.Result = noRows{}
 
 func (noRows) LastInsertId() (int64, error) {
-	return 0, errNoLastInsertId
+	return 0, errNoLastInsertID
 }
 
 func (noRows) RowsAffected() (int64, error) {
@@ -712,7 +706,7 @@ func (noRows) RowsAffected() (int64, error) {
 
 // Decides which column formats to use for a prepared statement.  The input is
 // an array of type oids, one element per result column.
-func decideColumnFormats(colTyps []oid.Oid, forceText bool) (colFmts []format, colFmtData []byte) {
+func decideColumnFormats(colTyps []fieldDesc, forceText bool) (colFmts []format, colFmtData []byte) {
 	if len(colTyps) == 0 {
 		return nil, colFmtDataAllText
 	}
@@ -724,8 +718,8 @@ func decideColumnFormats(colTyps []oid.Oid, forceText bool) (colFmts []format, c
 
 	allBinary := true
 	allText := true
-	for i, o := range colTyps {
+	for i, t := range colTyps {
-		switch o {
+		switch t.OID {
 		// This is the list of types to use binary mode for when receiving them
 		// through a prepared statement.  If a type appears in this list, it
 		// must also be implemented in binaryDecode in encode.go.
@@ -845,7 +839,7 @@ func (cn *conn) query(query string, args []driver.Value) (_ *rows, err error) {
 		rows.colNames, rows.colFmts, rows.colTyps = cn.readPortalDescribeResponse()
 		cn.postExecuteWorkaround()
 		return rows, nil
-	} else {
+	}
 	st := cn.prepareTo(query, "")
 	st.exec(args)
 	return &rows{
@@ -855,7 +849,6 @@ func (cn *conn) query(query string, args []driver.Value) (_ *rows, err error) {
 		colFmts:  st.colFmts,
 	}, nil
 }
-}
 
 // Implement the optional "Execer" interface for one-shot queries
 func (cn *conn) Exec(query string, args []driver.Value) (res driver.Result, err error) {
@@ -881,7 +874,7 @@ func (cn *conn) Exec(query string, args []driver.Value) (res driver.Result, err
 		cn.postExecuteWorkaround()
 		res, _, err = cn.readExecuteResponse("Execute")
 		return res, err
-	} else {
+	}
 	// Use the unnamed statement to defer planning until bind
 	// time, or else value-based selectivity estimates cannot be
 	// used.
@@ -892,7 +885,6 @@ func (cn *conn) Exec(query string, args []driver.Value) (res driver.Result, err
 	}
 	return r, err
 }
-}
 
 func (cn *conn) send(m *writeBuf) {
 	_, err := cn.c.Write(m.wrap())
@@ -901,16 +893,9 @@ func (cn *conn) send(m *writeBuf) {
 	}
 }
 
-func (cn *conn) sendStartupPacket(m *writeBuf) {
+func (cn *conn) sendStartupPacket(m *writeBuf) error {
-	// sanity check
-	if m.buf[0] != 0 {
-		panic("oops")
-	}
-
 	_, err := cn.c.Write((m.wrap())[1:])
-	if err != nil {
+	return err
-		panic(err)
-	}
 }
 
 // Send a message of type typ to the server on the other end of cn.  The
@@ -1032,7 +1017,9 @@ func (cn *conn) ssl(o values) {
 
 	w := cn.writeBuf(0)
 	w.int32(80877103)
-	cn.sendStartupPacket(w)
+	if err := cn.sendStartupPacket(w); err != nil {
+		panic(err)
+	}
 
 	b := cn.scratch[:1]
 	_, err := io.ReadFull(cn.c, b)
@@ -1093,7 +1080,9 @@ func (cn *conn) startup(o values) {
 		w.string(v)
 	}
 	w.string("")
-	cn.sendStartupPacket(w)
+	if err := cn.sendStartupPacket(w); err != nil {
+		panic(err)
+	}
 
 	for {
 		t, r := cn.recv()
@@ -1119,7 +1108,7 @@ func (cn *conn) auth(r *readBuf, o values) {
 		// OK
 	case 3:
 		w := cn.writeBuf('p')
-		w.string(o.Get("password"))
+		w.string(o["password"])
 		cn.send(w)
 
 		t, r := cn.recv()
@@ -1133,7 +1122,7 @@ func (cn *conn) auth(r *readBuf, o values) {
 	case 5:
 		s := string(r.next(4))
 		w := cn.writeBuf('p')
-		w.string("md5" + md5s(md5s(o.Get("password")+o.Get("user"))+s))
+		w.string("md5" + md5s(md5s(o["password"]+o["user"])+s))
 		cn.send(w)
 
 		t, r := cn.recv()
@@ -1155,10 +1144,10 @@ const formatText format = 0
 const formatBinary format = 1
 
 // One result-column format code with the value 1 (i.e. all binary).
-var colFmtDataAllBinary []byte = []byte{0, 1, 0, 1}
+var colFmtDataAllBinary = []byte{0, 1, 0, 1}
 
 // No result-column format codes (i.e. all text).
-var colFmtDataAllText []byte = []byte{0, 0}
+var colFmtDataAllText = []byte{0, 0}
 
 type stmt struct {
 	cn         *conn
@@ -1166,7 +1155,7 @@ type stmt struct {
 	colNames   []string
 	colFmts    []format
 	colFmtData []byte
-	colTyps    []oid.Oid
+	colTyps    []fieldDesc
 	paramTyps  []oid.Oid
 	closed     bool
 }
@@ -1327,17 +1316,19 @@ func (cn *conn) parseComplete(commandTag string) (driver.Result, string) {
 
 type rows struct {
 	cn       *conn
-	closed   chan<- struct{}
+	finish   func()
 	colNames []string
-	colTyps  []oid.Oid
+	colTyps  []fieldDesc
 	colFmts  []format
 	done     bool
 	rb       readBuf
+	result   driver.Result
+	tag      string
 }
 
 func (rs *rows) Close() error {
-	if rs.closed != nil {
+	if finish := rs.finish; finish != nil {
-		defer close(rs.closed)
+		defer finish()
 	}
 	// no need to look at cn.bad as Next() will
 	for {
@@ -1345,7 +1336,12 @@ func (rs *rows) Close() error {
 		switch err {
 		case nil:
 		case io.EOF:
+			// rs.Next can return io.EOF on both 'Z' (ready for query) and 'T' (row
+			// description, used with HasNextResultSet). We need to fetch messages until
+			// we hit a 'Z', which is done by waiting for done to be set.
+			if rs.done {
 				return nil
+			}
 		default:
 			return err
 		}
@@ -1356,6 +1352,17 @@ func (rs *rows) Columns() []string {
 	return rs.colNames
 }
 
+func (rs *rows) Result() driver.Result {
+	if rs.result == nil {
+		return emptyRows
+	}
+	return rs.result
+}
+
+func (rs *rows) Tag() string {
+	return rs.tag
+}
+
 func (rs *rows) Next(dest []driver.Value) (err error) {
 	if rs.done {
 		return io.EOF
@@ -1373,6 +1380,9 @@ func (rs *rows) Next(dest []driver.Value) (err error) {
 		case 'E':
 			err = parseError(&rs.rb)
 		case 'C', 'I':
+			if t == 'C' {
+				rs.result, rs.tag = conn.parseComplete(rs.rb.string())
+			}
 			continue
 		case 'Z':
 			conn.processReadyForQuery(&rs.rb)
@@ -1396,7 +1406,7 @@ func (rs *rows) Next(dest []driver.Value) (err error) {
 					dest[i] = nil
 					continue
 				}
-				dest[i] = decode(&conn.parameterStatus, rs.rb.next(l), rs.colTyps[i], rs.colFmts[i])
+				dest[i] = decode(&conn.parameterStatus, rs.rb.next(l), rs.colTyps[i].OID, rs.colFmts[i])
 			}
 			return
 		case 'T':
@@ -1502,7 +1512,7 @@ func (cn *conn) sendBinaryModeQuery(query string, args []driver.Value) {
 	cn.send(b)
 }
 
-func (c *conn) processParameterStatus(r *readBuf) {
+func (cn *conn) processParameterStatus(r *readBuf) {
 	var err error
 
 	param := r.string()
@@ -1513,13 +1523,13 @@ func (c *conn) processParameterStatus(r *readBuf) {
 		var minor int
 		_, err = fmt.Sscanf(r.string(), "%d.%d.%d", &major1, &major2, &minor)
 		if err == nil {
-			c.parameterStatus.serverVersion = major1*10000 + major2*100 + minor
+			cn.parameterStatus.serverVersion = major1*10000 + major2*100 + minor
 		}
 
 	case "TimeZone":
-		c.parameterStatus.currentLocation, err = time.LoadLocation(r.string())
+		cn.parameterStatus.currentLocation, err = time.LoadLocation(r.string())
 		if err != nil {
-			c.parameterStatus.currentLocation = nil
+			cn.parameterStatus.currentLocation = nil
 		}
 
 	default:
@@ -1527,8 +1537,8 @@ func (c *conn) processParameterStatus(r *readBuf) {
 	}
 }
 
-func (c *conn) processReadyForQuery(r *readBuf) {
+func (cn *conn) processReadyForQuery(r *readBuf) {
-	c.txnStatus = transactionStatus(r.byte())
+	cn.txnStatus = transactionStatus(r.byte())
 }
 
 func (cn *conn) readReadyForQuery() {
@@ -1543,9 +1553,9 @@ func (cn *conn) readReadyForQuery() {
 	}
 }
 
-func (c *conn) processBackendKeyData(r *readBuf) {
+func (cn *conn) processBackendKeyData(r *readBuf) {
-	c.processID = r.int32()
+	cn.processID = r.int32()
-	c.secretKey = r.int32()
+	cn.secretKey = r.int32()
 }
 
 func (cn *conn) readParseResponse() {
@@ -1563,7 +1573,7 @@ func (cn *conn) readParseResponse() {
 	}
 }
 
-func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames []string, colTyps []oid.Oid) {
+func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames []string, colTyps []fieldDesc) {
 	for {
 		t, r := cn.recv1()
 		switch t {
@@ -1589,7 +1599,7 @@ func (cn *conn) readStatementDescribeResponse() (paramTyps []oid.Oid, colNames [
 	}
 }
 
-func (cn *conn) readPortalDescribeResponse() (colNames []string, colFmts []format, colTyps []oid.Oid) {
+func (cn *conn) readPortalDescribeResponse() (colNames []string, colFmts []format, colTyps []fieldDesc) {
 	t, r := cn.recv1()
 	switch t {
 	case 'T':
@@ -1685,31 +1695,33 @@ func (cn *conn) readExecuteResponse(protocolState string) (res driver.Result, co
 	}
 }
 
-func parseStatementRowDescribe(r *readBuf) (colNames []string, colTyps []oid.Oid) {
+func parseStatementRowDescribe(r *readBuf) (colNames []string, colTyps []fieldDesc) {
 	n := r.int16()
 	colNames = make([]string, n)
-	colTyps = make([]oid.Oid, n)
+	colTyps = make([]fieldDesc, n)
 	for i := range colNames {
 		colNames[i] = r.string()
 		r.next(6)
-		colTyps[i] = r.oid()
+		colTyps[i].OID = r.oid()
-		r.next(6)
+		colTyps[i].Len = r.int16()
+		colTyps[i].Mod = r.int32()
 		// format code not known when describing a statement; always 0
 		r.next(2)
 	}
 	return
 }
 
-func parsePortalRowDescribe(r *readBuf) (colNames []string, colFmts []format, colTyps []oid.Oid) {
+func parsePortalRowDescribe(r *readBuf) (colNames []string, colFmts []format, colTyps []fieldDesc) {
 	n := r.int16()
 	colNames = make([]string, n)
 	colFmts = make([]format, n)
-	colTyps = make([]oid.Oid, n)
+	colTyps = make([]fieldDesc, n)
 	for i := range colNames {
 		colNames[i] = r.string()
 		r.next(6)
-		colTyps[i] = r.oid()
+		colTyps[i].OID = r.oid()
-		r.next(6)
+		colTyps[i].Len = r.int16()
+		colTyps[i].Mod = r.int32()
 		colFmts[i] = format(r.int16())
 	}
 	return

vendor/src/github.com/lib/pq/conn_go18.go

@@ -4,8 +4,11 @@ package pq
 
 import (
 	"context"
+	"database/sql"
 	"database/sql/driver"
-	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
 )
 
 // Implement the "QueryerContext" interface
@@ -14,15 +17,15 @@ func (cn *conn) QueryContext(ctx context.Context, query string, args []driver.Na
 	for i, nv := range args {
 		list[i] = nv.Value
 	}
-	var closed chan<- struct{}
+	finish := cn.watchCancel(ctx)
-	if ctx.Done() != nil {
-		closed = watchCancel(ctx, cn.cancel)
-	}
 	r, err := cn.query(query, list)
 	if err != nil {
+		if finish != nil {
+			finish()
+		}
 		return nil, err
 	}
-	r.closed = closed
+	r.finish = finish
 	return r, nil
 }
 
@@ -33,9 +36,8 @@ func (cn *conn) ExecContext(ctx context.Context, query string, args []driver.Nam
 		list[i] = nv.Value
 	}
 
-	if ctx.Done() != nil {
+	if finish := cn.watchCancel(ctx); finish != nil {
-		closed := watchCancel(ctx, cn.cancel)
+		defer finish()
-		defer close(closed)
 	}
 
 	return cn.Exec(query, list)
@@ -43,50 +45,84 @@ func (cn *conn) ExecContext(ctx context.Context, query string, args []driver.Nam
 
 // Implement the "ConnBeginTx" interface
 func (cn *conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
-	if opts.Isolation != 0 {
+	var mode string
-		return nil, errors.New("isolation levels not supported")
+
+	switch sql.IsolationLevel(opts.Isolation) {
+	case sql.LevelDefault:
+		// Don't touch mode: use the server's default
+	case sql.LevelReadUncommitted:
+		mode = " ISOLATION LEVEL READ UNCOMMITTED"
+	case sql.LevelReadCommitted:
+		mode = " ISOLATION LEVEL READ COMMITTED"
+	case sql.LevelRepeatableRead:
+		mode = " ISOLATION LEVEL REPEATABLE READ"
+	case sql.LevelSerializable:
+		mode = " ISOLATION LEVEL SERIALIZABLE"
+	default:
+		return nil, fmt.Errorf("pq: isolation level not supported: %d", opts.Isolation)
 	}
+
 	if opts.ReadOnly {
-		return nil, errors.New("read-only transactions not supported")
+		mode += " READ ONLY"
+	} else {
+		mode += " READ WRITE"
 	}
-	tx, err := cn.Begin()
+
+	tx, err := cn.begin(mode)
 	if err != nil {
 		return nil, err
 	}
-	if ctx.Done() != nil {
+	cn.txnFinish = cn.watchCancel(ctx)
-		cn.txnClosed = watchCancel(ctx, cn.cancel)
-	}
 	return tx, nil
 }
 
-func watchCancel(ctx context.Context, cancel func()) chan<- struct{} {
+func (cn *conn) watchCancel(ctx context.Context) func() {
-	closed := make(chan struct{})
+	if done := ctx.Done(); done != nil {
+		finished := make(chan struct{})
 		go func() {
 			select {
-		case <-ctx.Done():
+			case <-done:
-			cancel()
+				_ = cn.cancel()
-		case <-closed:
+				finished <- struct{}{}
+			case <-finished:
 			}
 		}()
-	return closed
+		return func() {
+			select {
+			case <-finished:
+			case finished <- struct{}{}:
+			}
+		}
+	}
+	return nil
 }
 
-func (cn *conn) cancel() {
+func (cn *conn) cancel() error {
-	var err error
+	c, err := dial(cn.dialer, cn.opts)
-	can := &conn{}
-	can.c, err = dial(cn.dialer, cn.opts)
 	if err != nil {
-		return
+		return err
+	}
+	defer c.Close()
+
+	{
+		can := conn{
+			c: c,
 		}
 		can.ssl(cn.opts)
 
-	defer can.errRecover(&err)
-
 		w := can.writeBuf(0)
 		w.int32(80877102) // cancel request code
 		w.int32(cn.processID)
 		w.int32(cn.secretKey)
 
-	can.sendStartupPacket(w)
+		if err := can.sendStartupPacket(w); err != nil {
-	_ = can.c.Close()
+			return err
+		}
+	}
+
+	// Read until EOF to ensure that the server received the cancel.
+	{
+		_, err := io.Copy(ioutil.Discard, c)
+		return err
+	}
 }

vendor/src/github.com/lib/pq/conn_test.go

@@ -136,7 +136,7 @@ func TestOpenURL(t *testing.T) {
 	testURL("postgresql://")
 }
 
-const pgpass_file = "/tmp/pqgotest_pgpass"
+const pgpassFile = "/tmp/pqgotest_pgpass"
 
 func TestPgpass(t *testing.T) {
 	if os.Getenv("TRAVIS") != "true" {
@@ -160,11 +160,11 @@ func TestPgpass(t *testing.T) {
 		rows, err := txn.Query("SELECT USER")
 		if err != nil {
 			txn.Rollback()
-			rows.Close()
 			if expected != "fail" {
 				t.Fatalf(reason, err)
 			}
 		} else {
+			rows.Close()
 			if expected != "ok" {
 				t.Fatalf(reason, err)
 			}
@@ -172,10 +172,10 @@ func TestPgpass(t *testing.T) {
 		txn.Rollback()
 	}
 	testAssert("", "ok", "missing .pgpass, unexpected error %#v")
-	os.Setenv("PGPASSFILE", pgpass_file)
+	os.Setenv("PGPASSFILE", pgpassFile)
 	testAssert("host=/tmp", "fail", ", unexpected error %#v")
-	os.Remove(pgpass_file)
+	os.Remove(pgpassFile)
-	pgpass, err := os.OpenFile(pgpass_file, os.O_RDWR|os.O_CREATE, 0644)
+	pgpass, err := os.OpenFile(pgpassFile, os.O_RDWR|os.O_CREATE, 0644)
 	if err != nil {
 		t.Fatalf("Unexpected error writing pgpass file %#v", err)
 	}
@@ -191,7 +191,7 @@ localhost:*:*:*:pass_C
 	pgpass.Close()
 
 	assertPassword := func(extra values, expected string) {
-		o := &values{
+		o := values{
 			"host":               "localhost",
 			"sslmode":            "disable",
 			"connect_timeout":    "20",
@@ -203,17 +203,17 @@ localhost:*:*:*:pass_C
 			"datestyle":          "ISO, MDY",
 		}
 		for k, v := range extra {
-			(*o)[k] = v
+			o[k] = v
 		}
-		(&conn{}).handlePgpass(*o)
+		(&conn{}).handlePgpass(o)
-		if o.Get("password") != expected {
+		if pw := o["password"]; pw != expected {
-			t.Fatalf("For %v expected %s got %s", extra, expected, o.Get("password"))
+			t.Fatalf("For %v expected %s got %s", extra, expected, pw)
 		}
 	}
 	// wrong permissions for the pgpass file means it should be ignored
 	assertPassword(values{"host": "example.com", "user": "foo"}, "")
 	// fix the permissions and check if it has taken effect
-	os.Chmod(pgpass_file, 0600)
+	os.Chmod(pgpassFile, 0600)
 	assertPassword(values{"host": "server", "dbname": "some_db", "user": "some_user"}, "pass_A")
 	assertPassword(values{"host": "example.com", "user": "foo"}, "pass_fallback")
 	assertPassword(values{"host": "example.com", "dbname": "some_db", "user": "some_user"}, "pass_B")
@@ -221,7 +221,7 @@ localhost:*:*:*:pass_C
 	assertPassword(values{"host": "", "user": "some_user"}, "pass_C")
 	assertPassword(values{"host": "/tmp", "user": "some_user"}, "pass_C")
 	// cleanup
-	os.Remove(pgpass_file)
+	os.Remove(pgpassFile)
 	os.Setenv("PGPASSFILE", "")
 }
 
@@ -393,8 +393,8 @@ func TestEmptyQuery(t *testing.T) {
 	if _, err := res.RowsAffected(); err != errNoRowsAffected {
 		t.Fatalf("expected %s, got %v", errNoRowsAffected, err)
 	}
-	if _, err := res.LastInsertId(); err != errNoLastInsertId {
+	if _, err := res.LastInsertId(); err != errNoLastInsertID {
-		t.Fatalf("expected %s, got %v", errNoLastInsertId, err)
+		t.Fatalf("expected %s, got %v", errNoLastInsertID, err)
 	}
 	rows, err := db.Query("")
 	if err != nil {
@@ -425,8 +425,8 @@ func TestEmptyQuery(t *testing.T) {
 	if _, err := res.RowsAffected(); err != errNoRowsAffected {
 		t.Fatalf("expected %s, got %v", errNoRowsAffected, err)
 	}
-	if _, err := res.LastInsertId(); err != errNoLastInsertId {
+	if _, err := res.LastInsertId(); err != errNoLastInsertID {
-		t.Fatalf("expected %s, got %v", errNoLastInsertId, err)
+		t.Fatalf("expected %s, got %v", errNoLastInsertID, err)
 	}
 	rows, err = stmt.Query()
 	if err != nil {
@@ -686,17 +686,28 @@ func TestCloseBadConn(t *testing.T) {
 	if err := cn.Close(); err != nil {
 		t.Fatal(err)
 	}
+
+	// During the Go 1.9 cycle, https://github.com/golang/go/commit/3792db5
+	// changed this error from
+	//
+	// net.errClosing = errors.New("use of closed network connection")
+	//
+	// to
+	//
+	// internal/poll.ErrClosing = errors.New("use of closed file or network connection")
+	const errClosing = "use of closed"
+
 	// Verify write after closing fails.
 	if _, err := nc.Write(nil); err == nil {
 		t.Fatal("expected error")
-	} else if !strings.Contains(err.Error(), "use of closed network connection") {
+	} else if !strings.Contains(err.Error(), errClosing) {
-		t.Fatalf("expected use of closed network connection error, got %s", err)
+		t.Fatalf("expected %s error, got %s", errClosing, err)
 	}
 	// Verify second close fails.
 	if err := cn.Close(); err == nil {
 		t.Fatal("expected error")
-	} else if !strings.Contains(err.Error(), "use of closed network connection") {
+	} else if !strings.Contains(err.Error(), errClosing) {
-		t.Fatalf("expected use of closed network connection error, got %s", err)
+		t.Fatalf("expected %s error, got %s", errClosing, err)
 	}
 }
 
@@ -1042,16 +1053,16 @@ func TestIssue282(t *testing.T) {
 	db := openTestConn(t)
 	defer db.Close()
 
-	var search_path string
+	var searchPath string
 	err := db.QueryRow(`
 		SET LOCAL search_path TO pg_catalog;
 		SET LOCAL search_path TO pg_catalog;
-		SHOW search_path`).Scan(&search_path)
+		SHOW search_path`).Scan(&searchPath)
 	if err != nil {
 		t.Fatal(err)
 	}
-	if search_path != "pg_catalog" {
+	if searchPath != "pg_catalog" {
-		t.Fatalf("unexpected search_path %s", search_path)
+		t.Fatalf("unexpected search_path %s", searchPath)
 	}
 }
 
@@ -1493,3 +1504,111 @@ func TestQuoteIdentifier(t *testing.T) {
 		}
 	}
 }
+
+func TestRowsResultTag(t *testing.T) {
+	type ResultTag interface {
+		Result() driver.Result
+		Tag() string
+	}
+
+	tests := []struct {
+		query string
+		tag   string
+		ra    int64
+	}{
+		{
+			query: "CREATE TEMP TABLE temp (a int)",
+			tag:   "CREATE TABLE",
+		},
+		{
+			query: "INSERT INTO temp VALUES (1), (2)",
+			tag:   "INSERT",
+			ra:    2,
+		},
+		{
+			query: "SELECT 1",
+		},
+		// A SELECT anywhere should take precedent.
+		{
+			query: "SELECT 1; INSERT INTO temp VALUES (1), (2)",
+		},
+		{
+			query: "INSERT INTO temp VALUES (1), (2); SELECT 1",
+		},
+		// Multiple statements that don't return rows should return the last tag.
+		{
+			query: "CREATE TEMP TABLE t (a int); DROP TABLE t",
+			tag:   "DROP TABLE",
+		},
+		// Ensure a rows-returning query in any position among various tags-returing
+		// statements will prefer the rows.
+		{
+			query: "SELECT 1; CREATE TEMP TABLE t (a int); DROP TABLE t",
+		},
+		{
+			query: "CREATE TEMP TABLE t (a int); SELECT 1; DROP TABLE t",
+		},
+		{
+			query: "CREATE TEMP TABLE t (a int); DROP TABLE t; SELECT 1",
+		},
+		// Verify that an no-results query doesn't set the tag.
+		{
+			query: "CREATE TEMP TABLE t (a int); SELECT 1 WHERE FALSE; DROP TABLE t;",
+		},
+	}
+
+	// If this is the only test run, this will correct the connection string.
+	openTestConn(t).Close()
+
+	conn, err := Open("")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	q := conn.(driver.Queryer)
+
+	for _, test := range tests {
+		if rows, err := q.Query(test.query, nil); err != nil {
+			t.Fatalf("%s: %s", test.query, err)
+		} else {
+			r := rows.(ResultTag)
+			if tag := r.Tag(); tag != test.tag {
+				t.Fatalf("%s: unexpected tag %q", test.query, tag)
+			}
+			res := r.Result()
+			if ra, _ := res.RowsAffected(); ra != test.ra {
+				t.Fatalf("%s: unexpected rows affected: %d", test.query, ra)
+			}
+			rows.Close()
+		}
+	}
+}
+
+// TestQuickClose tests that closing a query early allows a subsequent query to work.
+func TestQuickClose(t *testing.T) {
+	db := openTestConn(t)
+	defer db.Close()
+
+	tx, err := db.Begin()
+	if err != nil {
+		t.Fatal(err)
+	}
+	rows, err := tx.Query("SELECT 1; SELECT 2;")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := rows.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	var id int
+	if err := tx.QueryRow("SELECT 3").Scan(&id); err != nil {
+		t.Fatal(err)
+	}
+	if id != 3 {
+		t.Fatalf("unexpected %d", id)
+	}
+	if err := tx.Commit(); err != nil {
+		t.Fatal(err)
+	}
+}

vendor/src/github.com/lib/pq/encode_test.go

@@ -370,17 +370,17 @@ func TestInfinityTimestamp(t *testing.T) {
 		t.Errorf("Scanning -infinity, expected time %q, got %q", y1500, resultT.String())
 	}
 
-	y_1500 := time.Date(-1500, time.January, 1, 0, 0, 0, 0, time.UTC)
+	ym1500 := time.Date(-1500, time.January, 1, 0, 0, 0, 0, time.UTC)
 	y11500 := time.Date(11500, time.January, 1, 0, 0, 0, 0, time.UTC)
 	var s string
-	err = db.QueryRow("SELECT $1::timestamp::text", y_1500).Scan(&s)
+	err = db.QueryRow("SELECT $1::timestamp::text", ym1500).Scan(&s)
 	if err != nil {
 		t.Errorf("Encoding -infinity, expected no error, got %q", err)
 	}
 	if s != "-infinity" {
 		t.Errorf("Encoding -infinity, expected %q, got %q", "-infinity", s)
 	}
-	err = db.QueryRow("SELECT $1::timestamptz::text", y_1500).Scan(&s)
+	err = db.QueryRow("SELECT $1::timestamptz::text", ym1500).Scan(&s)
 	if err != nil {
 		t.Errorf("Encoding -infinity, expected no error, got %q", err)
 	}

vendor/src/github.com/lib/pq/go18_test.go

@@ -5,6 +5,8 @@ package pq
 import (
 	"context"
 	"database/sql"
+	"runtime"
+	"strings"
 	"testing"
 	"time"
 )
@@ -72,6 +74,8 @@ func TestMultipleSimpleQuery(t *testing.T) {
 	}
 }
 
+const contextRaceIterations = 100
+
 func TestContextCancelExec(t *testing.T) {
 	db := openTestConn(t)
 	defer db.Close()
@@ -79,10 +83,7 @@ func TestContextCancelExec(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 
 	// Delay execution for just a bit until db.ExecContext has begun.
-	go func() {
+	defer time.AfterFunc(time.Millisecond*10, cancel).Stop()
-		time.Sleep(time.Millisecond * 10)
-		cancel()
-	}()
 
 	// Not canceled until after the exec has started.
 	if _, err := db.ExecContext(ctx, "select pg_sleep(1)"); err == nil {
@@ -97,6 +98,20 @@ func TestContextCancelExec(t *testing.T) {
 	} else if err.Error() != "context canceled" {
 		t.Fatalf("unexpected error: %s", err)
 	}
+
+	for i := 0; i < contextRaceIterations; i++ {
+		func() {
+			ctx, cancel := context.WithCancel(context.Background())
+			defer cancel()
+			if _, err := db.ExecContext(ctx, "select 1"); err != nil {
+				t.Fatal(err)
+			}
+		}()
+
+		if _, err := db.Exec("select 1"); err != nil {
+			t.Fatal(err)
+		}
+	}
 }
 
 func TestContextCancelQuery(t *testing.T) {
@@ -106,10 +121,7 @@ func TestContextCancelQuery(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 
 	// Delay execution for just a bit until db.QueryContext has begun.
-	go func() {
+	defer time.AfterFunc(time.Millisecond*10, cancel).Stop()
-		time.Sleep(time.Millisecond * 10)
-		cancel()
-	}()
 
 	// Not canceled until after the exec has started.
 	if _, err := db.QueryContext(ctx, "select pg_sleep(1)"); err == nil {
@@ -124,6 +136,55 @@ func TestContextCancelQuery(t *testing.T) {
 	} else if err.Error() != "context canceled" {
 		t.Fatalf("unexpected error: %s", err)
 	}
+
+	for i := 0; i < contextRaceIterations; i++ {
+		func() {
+			ctx, cancel := context.WithCancel(context.Background())
+			rows, err := db.QueryContext(ctx, "select 1")
+			cancel()
+			if err != nil {
+				t.Fatal(err)
+			} else if err := rows.Close(); err != nil {
+				t.Fatal(err)
+			}
+		}()
+
+		if rows, err := db.Query("select 1"); err != nil {
+			t.Fatal(err)
+		} else if err := rows.Close(); err != nil {
+			t.Fatal(err)
+		}
+	}
+}
+
+// TestIssue617 tests that a failed query in QueryContext doesn't lead to a
+// goroutine leak.
+func TestIssue617(t *testing.T) {
+	db := openTestConn(t)
+	defer db.Close()
+
+	const N = 10
+
+	numGoroutineStart := runtime.NumGoroutine()
+	for i := 0; i < N; i++ {
+		func() {
+			ctx, cancel := context.WithCancel(context.Background())
+			defer cancel()
+			_, err := db.QueryContext(ctx, `SELECT * FROM DOESNOTEXIST`)
+			pqErr, _ := err.(*Error)
+			// Expecting "pq: relation \"doesnotexist\" does not exist" error.
+			if err == nil || pqErr == nil || pqErr.Code != "42P01" {
+				t.Fatalf("expected undefined table error, got %v", err)
+			}
+		}()
+	}
+	numGoroutineFinish := runtime.NumGoroutine()
+
+	// We use N/2 and not N because the GC and other actors may increase or
+	// decrease the number of goroutines.
+	if numGoroutineFinish-numGoroutineStart >= N/2 {
+		t.Errorf("goroutine leak detected, was %d, now %d", numGoroutineStart, numGoroutineFinish)
+	}
 }
 
 func TestContextCancelBegin(t *testing.T) {
@@ -137,10 +198,7 @@ func TestContextCancelBegin(t *testing.T) {
 	}
 
 	// Delay execution for just a bit until tx.Exec has begun.
-	go func() {
+	defer time.AfterFunc(time.Millisecond*10, cancel).Stop()
-		time.Sleep(time.Millisecond * 10)
-		cancel()
-	}()
 
 	// Not canceled until after the exec has started.
 	if _, err := tx.Exec("select pg_sleep(1)"); err == nil {
@@ -162,4 +220,100 @@ func TestContextCancelBegin(t *testing.T) {
 	} else if err.Error() != "context canceled" {
 		t.Fatalf("unexpected error: %s", err)
 	}
+
+	for i := 0; i < contextRaceIterations; i++ {
+		func() {
+			ctx, cancel := context.WithCancel(context.Background())
+			tx, err := db.BeginTx(ctx, nil)
+			cancel()
+			if err != nil {
+				t.Fatal(err)
+			} else if err := tx.Rollback(); err != nil && err != sql.ErrTxDone {
+				t.Fatal(err)
+			}
+		}()
+
+		if tx, err := db.Begin(); err != nil {
+			t.Fatal(err)
+		} else if err := tx.Rollback(); err != nil {
+			t.Fatal(err)
+		}
+	}
+}
+
+func TestTxOptions(t *testing.T) {
+	db := openTestConn(t)
+	defer db.Close()
+	ctx := context.Background()
+
+	tests := []struct {
+		level     sql.IsolationLevel
+		isolation string
+	}{
+		{
+			level:     sql.LevelDefault,
+			isolation: "",
+		},
+		{
+			level:     sql.LevelReadUncommitted,
+			isolation: "read uncommitted",
+		},
+		{
+			level:     sql.LevelReadCommitted,
+			isolation: "read committed",
+		},
+		{
+			level:     sql.LevelRepeatableRead,
+			isolation: "repeatable read",
+		},
+		{
+			level:     sql.LevelSerializable,
+			isolation: "serializable",
+		},
+	}
+
+	for _, test := range tests {
+		for _, ro := range []bool{true, false} {
+			tx, err := db.BeginTx(ctx, &sql.TxOptions{
+				Isolation: test.level,
+				ReadOnly:  ro,
+			})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			var isolation string
+			err = tx.QueryRow("select current_setting('transaction_isolation')").Scan(&isolation)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if test.isolation != "" && isolation != test.isolation {
+				t.Errorf("wrong isolation level: %s != %s", isolation, test.isolation)
+			}
+
+			var isRO string
+			err = tx.QueryRow("select current_setting('transaction_read_only')").Scan(&isRO)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if ro != (isRO == "on") {
+				t.Errorf("read/[write,only] not set: %t != %s for level %s",
+					ro, isRO, test.isolation)
+			}
+
+			tx.Rollback()
+		}
+	}
+
+	_, err := db.BeginTx(ctx, &sql.TxOptions{
+		Isolation: sql.LevelLinearizable,
+	})
+	if err == nil {
+		t.Fatal("expected LevelLinearizable to fail")
+	}
+	if !strings.Contains(err.Error(), "isolation level not supported") {
+		t.Errorf("Expected error to mention isolation level, got %q", err)
+	}
 }

vendor/src/github.com/lib/pq/listen_example/doc.go

@@ -51,21 +51,15 @@ mechanism to avoid polling the database while waiting for more work to arrive.
     }
 
     func waitForNotification(l *pq.Listener) {
-        for {
         select {
             case <-l.Notify:
                 fmt.Println("received notification, new work available")
-                    return
             case <-time.After(90 * time.Second):
-                    go func() {
+                go l.Ping()
-                        l.Ping()
-                    }()
                 // Check if there's more work available, just in case it takes
                 // a while for the Listener to notice connection loss and
                 // reconnect.
                 fmt.Println("received no work for 90 seconds, checking for new work")
-                    return
-            }
         }
     }
 

vendor/src/github.com/lib/pq/notify_test.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"runtime"
 	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 )
@@ -235,15 +234,10 @@ func TestConnExecDeadlock(t *testing.T) {
 	// calls Close on the net.Conn; equivalent to a network failure
 	l.Close()
 
-	var done int32 = 0
+	defer time.AfterFunc(10*time.Second, func() {
-	go func() {
-		time.Sleep(10 * time.Second)
-		if atomic.LoadInt32(&done) != 1 {
 		panic("timed out")
-		}
+	}).Stop()
-	}()
 	wg.Wait()
-	atomic.StoreInt32(&done, 1)
 }
 
 // Test for ListenerConn being closed while a slow query is executing
@@ -271,15 +265,11 @@ func TestListenerConnCloseWhileQueryIsExecuting(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	var done int32 = 0
+
-	go func() {
+	defer time.AfterFunc(10*time.Second, func() {
-		time.Sleep(10 * time.Second)
-		if atomic.LoadInt32(&done) != 1 {
 		panic("timed out")
-		}
+	}).Stop()
-	}()
 	wg.Wait()
-	atomic.StoreInt32(&done, 1)
 }
 
 func TestNotifyExtra(t *testing.T) {

vendor/src/github.com/lib/pq/oid/gen.go

@@ -10,10 +10,22 @@ import (
 	"log"
 	"os"
 	"os/exec"
+	"strings"
 
 	_ "github.com/lib/pq"
 )
 
+// OID represent a postgres Object Identifier Type.
+type OID struct {
+	ID   int
+	Type string
+}
+
+// Name returns an upper case version of the oid type.
+func (o OID) Name() string {
+	return strings.ToUpper(o.Type)
+}
+
 func main() {
 	datname := os.Getenv("PGDATABASE")
 	sslmode := os.Getenv("PGSSLMODE")
@@ -30,6 +42,25 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
+	rows, err := db.Query(`
+		SELECT typname, oid
+		FROM pg_type WHERE oid < 10000
+		ORDER BY oid;
+	`)
+	if err != nil {
+		log.Fatal(err)
+	}
+	oids := make([]*OID, 0)
+	for rows.Next() {
+		var oid OID
+		if err = rows.Scan(&oid.Type, &oid.ID); err != nil {
+			log.Fatal(err)
+		}
+		oids = append(oids, &oid)
+	}
+	if err = rows.Err(); err != nil {
+		log.Fatal(err)
+	}
 	cmd := exec.Command("gofmt")
 	cmd.Stderr = os.Stderr
 	w, err := cmd.StdinPipe()
@@ -45,30 +76,18 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	fmt.Fprintln(w, "// generated by 'go run gen.go'; do not edit")
+	fmt.Fprintln(w, "// Code generated by gen.go. DO NOT EDIT.")
 	fmt.Fprintln(w, "\npackage oid")
 	fmt.Fprintln(w, "const (")
-	rows, err := db.Query(`
+	for _, oid := range oids {
-		SELECT typname, oid
+		fmt.Fprintf(w, "T_%s Oid = %d\n", oid.Type, oid.ID)
-		FROM pg_type WHERE oid < 10000
-		ORDER BY oid;
-	`)
-	if err != nil {
-		log.Fatal(err)
-	}
-	var name string
-	var oid int
-	for rows.Next() {
-		err = rows.Scan(&name, &oid)
-		if err != nil {
-			log.Fatal(err)
-		}
-		fmt.Fprintf(w, "T_%s Oid = %d\n", name, oid)
-	}
-	if err = rows.Err(); err != nil {
-		log.Fatal(err)
 	}
 	fmt.Fprintln(w, ")")
+	fmt.Fprintln(w, "var TypeName = map[Oid]string{")
+	for _, oid := range oids {
+		fmt.Fprintf(w, "T_%s: \"%s\",\n", oid.Type, oid.Name())
+	}
+	fmt.Fprintln(w, "}")
 	w.Close()
 	cmd.Wait()
 }

vendor/src/github.com/lib/pq/oid/types.go

@@ -1,4 +1,4 @@
-// generated by 'go run gen.go'; do not edit
+// Code generated by gen.go. DO NOT EDIT.
 
 package oid
 
@@ -18,6 +18,7 @@ const (
 	T_xid              Oid = 28
 	T_cid              Oid = 29
 	T_oidvector        Oid = 30
+	T_pg_ddl_command   Oid = 32
 	T_pg_type          Oid = 71
 	T_pg_attribute     Oid = 75
 	T_pg_proc          Oid = 81
@@ -28,6 +29,7 @@ const (
 	T_pg_node_tree     Oid = 194
 	T__json            Oid = 199
 	T_smgr             Oid = 210
+	T_index_am_handler Oid = 325
 	T_point            Oid = 600
 	T_lseg             Oid = 601
 	T_path             Oid = 602
@@ -133,6 +135,9 @@ const (
 	T__uuid            Oid = 2951
 	T_txid_snapshot    Oid = 2970
 	T_fdw_handler      Oid = 3115
+	T_pg_lsn           Oid = 3220
+	T__pg_lsn          Oid = 3221
+	T_tsm_handler      Oid = 3310
 	T_anyenum          Oid = 3500
 	T_tsvector         Oid = 3614
 	T_tsquery          Oid = 3615
@@ -144,6 +149,8 @@ const (
 	T__regconfig       Oid = 3735
 	T_regdictionary    Oid = 3769
 	T__regdictionary   Oid = 3770
+	T_jsonb            Oid = 3802
+	T__jsonb           Oid = 3807
 	T_anyrange         Oid = 3831
 	T_event_trigger    Oid = 3838
 	T_int4range        Oid = 3904
@@ -158,4 +165,179 @@ const (
 	T__daterange       Oid = 3913
 	T_int8range        Oid = 3926
 	T__int8range       Oid = 3927
+	T_pg_shseclabel    Oid = 4066
+	T_regnamespace     Oid = 4089
+	T__regnamespace    Oid = 4090
+	T_regrole          Oid = 4096
+	T__regrole         Oid = 4097
 )
+
+var TypeName = map[Oid]string{
+	T_bool:             "BOOL",
+	T_bytea:            "BYTEA",
+	T_char:             "CHAR",
+	T_name:             "NAME",
+	T_int8:             "INT8",
+	T_int2:             "INT2",
+	T_int2vector:       "INT2VECTOR",
+	T_int4:             "INT4",
+	T_regproc:          "REGPROC",
+	T_text:             "TEXT",
+	T_oid:              "OID",
+	T_tid:              "TID",
+	T_xid:              "XID",
+	T_cid:              "CID",
+	T_oidvector:        "OIDVECTOR",
+	T_pg_ddl_command:   "PG_DDL_COMMAND",
+	T_pg_type:          "PG_TYPE",
+	T_pg_attribute:     "PG_ATTRIBUTE",
+	T_pg_proc:          "PG_PROC",
+	T_pg_class:         "PG_CLASS",
+	T_json:             "JSON",
+	T_xml:              "XML",
+	T__xml:             "_XML",
+	T_pg_node_tree:     "PG_NODE_TREE",
+	T__json:            "_JSON",
+	T_smgr:             "SMGR",
+	T_index_am_handler: "INDEX_AM_HANDLER",
+	T_point:            "POINT",
+	T_lseg:             "LSEG",
+	T_path:             "PATH",
+	T_box:              "BOX",
+	T_polygon:          "POLYGON",
+	T_line:             "LINE",
+	T__line:            "_LINE",
+	T_cidr:             "CIDR",
+	T__cidr:            "_CIDR",
+	T_float4:           "FLOAT4",
+	T_float8:           "FLOAT8",
+	T_abstime:          "ABSTIME",
+	T_reltime:          "RELTIME",
+	T_tinterval:        "TINTERVAL",
+	T_unknown:          "UNKNOWN",
+	T_circle:           "CIRCLE",
+	T__circle:          "_CIRCLE",
+	T_money:            "MONEY",
+	T__money:           "_MONEY",
+	T_macaddr:          "MACADDR",
+	T_inet:             "INET",
+	T__bool:            "_BOOL",
+	T__bytea:           "_BYTEA",
+	T__char:            "_CHAR",
+	T__name:            "_NAME",
+	T__int2:            "_INT2",
+	T__int2vector:      "_INT2VECTOR",
+	T__int4:            "_INT4",
+	T__regproc:         "_REGPROC",
+	T__text:            "_TEXT",
+	T__tid:             "_TID",
+	T__xid:             "_XID",
+	T__cid:             "_CID",
+	T__oidvector:       "_OIDVECTOR",
+	T__bpchar:          "_BPCHAR",
+	T__varchar:         "_VARCHAR",
+	T__int8:            "_INT8",
+	T__point:           "_POINT",
+	T__lseg:            "_LSEG",
+	T__path:            "_PATH",
+	T__box:             "_BOX",
+	T__float4:          "_FLOAT4",
+	T__float8:          "_FLOAT8",
+	T__abstime:         "_ABSTIME",
+	T__reltime:         "_RELTIME",
+	T__tinterval:       "_TINTERVAL",
+	T__polygon:         "_POLYGON",
+	T__oid:             "_OID",
+	T_aclitem:          "ACLITEM",
+	T__aclitem:         "_ACLITEM",
+	T__macaddr:         "_MACADDR",
+	T__inet:            "_INET",
+	T_bpchar:           "BPCHAR",
+	T_varchar:          "VARCHAR",
+	T_date:             "DATE",
+	T_time:             "TIME",
+	T_timestamp:        "TIMESTAMP",
+	T__timestamp:       "_TIMESTAMP",
+	T__date:            "_DATE",
+	T__time:            "_TIME",
+	T_timestamptz:      "TIMESTAMPTZ",
+	T__timestamptz:     "_TIMESTAMPTZ",
+	T_interval:         "INTERVAL",
+	T__interval:        "_INTERVAL",
+	T__numeric:         "_NUMERIC",
+	T_pg_database:      "PG_DATABASE",
+	T__cstring:         "_CSTRING",
+	T_timetz:           "TIMETZ",
+	T__timetz:          "_TIMETZ",
+	T_bit:              "BIT",
+	T__bit:             "_BIT",
+	T_varbit:           "VARBIT",
+	T__varbit:          "_VARBIT",
+	T_numeric:          "NUMERIC",
+	T_refcursor:        "REFCURSOR",
+	T__refcursor:       "_REFCURSOR",
+	T_regprocedure:     "REGPROCEDURE",
+	T_regoper:          "REGOPER",
+	T_regoperator:      "REGOPERATOR",
+	T_regclass:         "REGCLASS",
+	T_regtype:          "REGTYPE",
+	T__regprocedure:    "_REGPROCEDURE",
+	T__regoper:         "_REGOPER",
+	T__regoperator:     "_REGOPERATOR",
+	T__regclass:        "_REGCLASS",
+	T__regtype:         "_REGTYPE",
+	T_record:           "RECORD",
+	T_cstring:          "CSTRING",
+	T_any:              "ANY",
+	T_anyarray:         "ANYARRAY",
+	T_void:             "VOID",
+	T_trigger:          "TRIGGER",
+	T_language_handler: "LANGUAGE_HANDLER",
+	T_internal:         "INTERNAL",
+	T_opaque:           "OPAQUE",
+	T_anyelement:       "ANYELEMENT",
+	T__record:          "_RECORD",
+	T_anynonarray:      "ANYNONARRAY",
+	T_pg_authid:        "PG_AUTHID",
+	T_pg_auth_members:  "PG_AUTH_MEMBERS",
+	T__txid_snapshot:   "_TXID_SNAPSHOT",
+	T_uuid:             "UUID",
+	T__uuid:            "_UUID",
+	T_txid_snapshot:    "TXID_SNAPSHOT",
+	T_fdw_handler:      "FDW_HANDLER",
+	T_pg_lsn:           "PG_LSN",
+	T__pg_lsn:          "_PG_LSN",
+	T_tsm_handler:      "TSM_HANDLER",
+	T_anyenum:          "ANYENUM",
+	T_tsvector:         "TSVECTOR",
+	T_tsquery:          "TSQUERY",
+	T_gtsvector:        "GTSVECTOR",
+	T__tsvector:        "_TSVECTOR",
+	T__gtsvector:       "_GTSVECTOR",
+	T__tsquery:         "_TSQUERY",
+	T_regconfig:        "REGCONFIG",
+	T__regconfig:       "_REGCONFIG",
+	T_regdictionary:    "REGDICTIONARY",
+	T__regdictionary:   "_REGDICTIONARY",
+	T_jsonb:            "JSONB",
+	T__jsonb:           "_JSONB",
+	T_anyrange:         "ANYRANGE",
+	T_event_trigger:    "EVENT_TRIGGER",
+	T_int4range:        "INT4RANGE",
+	T__int4range:       "_INT4RANGE",
+	T_numrange:         "NUMRANGE",
+	T__numrange:        "_NUMRANGE",
+	T_tsrange:          "TSRANGE",
+	T__tsrange:         "_TSRANGE",
+	T_tstzrange:        "TSTZRANGE",
+	T__tstzrange:       "_TSTZRANGE",
+	T_daterange:        "DATERANGE",
+	T__daterange:       "_DATERANGE",
+	T_int8range:        "INT8RANGE",
+	T__int8range:       "_INT8RANGE",
+	T_pg_shseclabel:    "PG_SHSECLABEL",
+	T_regnamespace:     "REGNAMESPACE",
+	T__regnamespace:    "_REGNAMESPACE",
+	T_regrole:          "REGROLE",
+	T__regrole:         "_REGROLE",
+}

vendor/src/github.com/lib/pq/rows.go

@@ -0,0 +1,93 @@
+package pq
+
+import (
+	"math"
+	"reflect"
+	"time"
+
+	"github.com/lib/pq/oid"
+)
+
+const headerSize = 4
+
+type fieldDesc struct {
+	// The object ID of the data type.
+	OID oid.Oid
+	// The data type size (see pg_type.typlen).
+	// Note that negative values denote variable-width types.
+	Len int
+	// The type modifier (see pg_attribute.atttypmod).
+	// The meaning of the modifier is type-specific.
+	Mod int
+}
+
+func (fd fieldDesc) Type() reflect.Type {
+	switch fd.OID {
+	case oid.T_int8:
+		return reflect.TypeOf(int64(0))
+	case oid.T_int4:
+		return reflect.TypeOf(int32(0))
+	case oid.T_int2:
+		return reflect.TypeOf(int16(0))
+	case oid.T_varchar, oid.T_text:
+		return reflect.TypeOf("")
+	case oid.T_bool:
+		return reflect.TypeOf(false)
+	case oid.T_date, oid.T_time, oid.T_timetz, oid.T_timestamp, oid.T_timestamptz:
+		return reflect.TypeOf(time.Time{})
+	case oid.T_bytea:
+		return reflect.TypeOf([]byte(nil))
+	default:
+		return reflect.TypeOf(new(interface{})).Elem()
+	}
+}
+
+func (fd fieldDesc) Name() string {
+	return oid.TypeName[fd.OID]
+}
+
+func (fd fieldDesc) Length() (length int64, ok bool) {
+	switch fd.OID {
+	case oid.T_text, oid.T_bytea:
+		return math.MaxInt64, true
+	case oid.T_varchar, oid.T_bpchar:
+		return int64(fd.Mod - headerSize), true
+	default:
+		return 0, false
+	}
+}
+
+func (fd fieldDesc) PrecisionScale() (precision, scale int64, ok bool) {
+	switch fd.OID {
+	case oid.T_numeric, oid.T__numeric:
+		mod := fd.Mod - headerSize
+		precision = int64((mod >> 16) & 0xffff)
+		scale = int64(mod & 0xffff)
+		return precision, scale, true
+	default:
+		return 0, 0, false
+	}
+}
+
+// ColumnTypeScanType returns the value type that can be used to scan types into.
+func (rs *rows) ColumnTypeScanType(index int) reflect.Type {
+	return rs.colTyps[index].Type()
+}
+
+// ColumnTypeDatabaseTypeName return the database system type name.
+func (rs *rows) ColumnTypeDatabaseTypeName(index int) string {
+	return rs.colTyps[index].Name()
+}
+
+// ColumnTypeLength returns the length of the column type if the column is a
+// variable length type. If the column is not a variable length type ok
+// should return false.
+func (rs *rows) ColumnTypeLength(index int) (length int64, ok bool) {
+	return rs.colTyps[index].Length()
+}
+
+// ColumnTypePrecisionScale should return the precision and scale for decimal
+// types. If not applicable, ok should be false.
+func (rs *rows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
+	return rs.colTyps[index].PrecisionScale()
+}

vendor/src/github.com/lib/pq/rows_test.go

@@ -0,0 +1,220 @@
+// +build go1.8
+
+package pq
+
+import (
+	"math"
+	"reflect"
+	"testing"
+
+	"github.com/lib/pq/oid"
+)
+
+func TestDataTypeName(t *testing.T) {
+	tts := []struct {
+		typ  oid.Oid
+		name string
+	}{
+		{oid.T_int8, "INT8"},
+		{oid.T_int4, "INT4"},
+		{oid.T_int2, "INT2"},
+		{oid.T_varchar, "VARCHAR"},
+		{oid.T_text, "TEXT"},
+		{oid.T_bool, "BOOL"},
+		{oid.T_numeric, "NUMERIC"},
+		{oid.T_date, "DATE"},
+		{oid.T_time, "TIME"},
+		{oid.T_timetz, "TIMETZ"},
+		{oid.T_timestamp, "TIMESTAMP"},
+		{oid.T_timestamptz, "TIMESTAMPTZ"},
+		{oid.T_bytea, "BYTEA"},
+	}
+
+	for i, tt := range tts {
+		dt := fieldDesc{OID: tt.typ}
+		if name := dt.Name(); name != tt.name {
+			t.Errorf("(%d) got: %s want: %s", i, name, tt.name)
+		}
+	}
+}
+
+func TestDataType(t *testing.T) {
+	tts := []struct {
+		typ  oid.Oid
+		kind reflect.Kind
+	}{
+		{oid.T_int8, reflect.Int64},
+		{oid.T_int4, reflect.Int32},
+		{oid.T_int2, reflect.Int16},
+		{oid.T_varchar, reflect.String},
+		{oid.T_text, reflect.String},
+		{oid.T_bool, reflect.Bool},
+		{oid.T_date, reflect.Struct},
+		{oid.T_time, reflect.Struct},
+		{oid.T_timetz, reflect.Struct},
+		{oid.T_timestamp, reflect.Struct},
+		{oid.T_timestamptz, reflect.Struct},
+		{oid.T_bytea, reflect.Slice},
+	}
+
+	for i, tt := range tts {
+		dt := fieldDesc{OID: tt.typ}
+		if kind := dt.Type().Kind(); kind != tt.kind {
+			t.Errorf("(%d) got: %s want: %s", i, kind, tt.kind)
+		}
+	}
+}
+
+func TestDataTypeLength(t *testing.T) {
+	tts := []struct {
+		typ    oid.Oid
+		len    int
+		mod    int
+		length int64
+		ok     bool
+	}{
+		{oid.T_int4, 0, -1, 0, false},
+		{oid.T_varchar, 65535, 9, 5, true},
+		{oid.T_text, 65535, -1, math.MaxInt64, true},
+		{oid.T_bytea, 65535, -1, math.MaxInt64, true},
+	}
+
+	for i, tt := range tts {
+		dt := fieldDesc{OID: tt.typ, Len: tt.len, Mod: tt.mod}
+		if l, k := dt.Length(); k != tt.ok || l != tt.length {
+			t.Errorf("(%d) got: %d, %t want: %d, %t", i, l, k, tt.length, tt.ok)
+		}
+	}
+}
+
+func TestDataTypePrecisionScale(t *testing.T) {
+	tts := []struct {
+		typ              oid.Oid
+		mod              int
+		precision, scale int64
+		ok               bool
+	}{
+		{oid.T_int4, -1, 0, 0, false},
+		{oid.T_numeric, 589830, 9, 2, true},
+		{oid.T_text, -1, 0, 0, false},
+	}
+
+	for i, tt := range tts {
+		dt := fieldDesc{OID: tt.typ, Mod: tt.mod}
+		p, s, k := dt.PrecisionScale()
+		if k != tt.ok {
+			t.Errorf("(%d) got: %t want: %t", i, k, tt.ok)
+		}
+		if p != tt.precision {
+			t.Errorf("(%d) wrong precision got: %d want: %d", i, p, tt.precision)
+		}
+		if s != tt.scale {
+			t.Errorf("(%d) wrong scale got: %d want: %d", i, s, tt.scale)
+		}
+	}
+}
+
+func TestRowsColumnTypes(t *testing.T) {
+	columnTypesTests := []struct {
+		Name     string
+		TypeName string
+		Length   struct {
+			Len int64
+			OK  bool
+		}
+		DecimalSize struct {
+			Precision int64
+			Scale     int64
+			OK        bool
+		}
+		ScanType reflect.Type
+	}{
+		{
+			Name:     "a",
+			TypeName: "INT4",
+			Length: struct {
+				Len int64
+				OK  bool
+			}{
+				Len: 0,
+				OK:  false,
+			},
+			DecimalSize: struct {
+				Precision int64
+				Scale     int64
+				OK        bool
+			}{
+				Precision: 0,
+				Scale:     0,
+				OK:        false,
+			},
+			ScanType: reflect.TypeOf(int32(0)),
+		}, {
+			Name:     "bar",
+			TypeName: "TEXT",
+			Length: struct {
+				Len int64
+				OK  bool
+			}{
+				Len: math.MaxInt64,
+				OK:  true,
+			},
+			DecimalSize: struct {
+				Precision int64
+				Scale     int64
+				OK        bool
+			}{
+				Precision: 0,
+				Scale:     0,
+				OK:        false,
+			},
+			ScanType: reflect.TypeOf(""),
+		},
+	}
+
+	db := openTestConn(t)
+	defer db.Close()
+
+	rows, err := db.Query("SELECT 1 AS a, text 'bar' AS bar, 1.28::numeric(9, 2) AS dec")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	columns, err := rows.ColumnTypes()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(columns) != 3 {
+		t.Errorf("expected 3 columns found %d", len(columns))
+	}
+
+	for i, tt := range columnTypesTests {
+		c := columns[i]
+		if c.Name() != tt.Name {
+			t.Errorf("(%d) got: %s, want: %s", i, c.Name(), tt.Name)
+		}
+		if c.DatabaseTypeName() != tt.TypeName {
+			t.Errorf("(%d) got: %s, want: %s", i, c.DatabaseTypeName(), tt.TypeName)
+		}
+		l, ok := c.Length()
+		if l != tt.Length.Len {
+			t.Errorf("(%d) got: %d, want: %d", i, l, tt.Length.Len)
+		}
+		if ok != tt.Length.OK {
+			t.Errorf("(%d) got: %t, want: %t", i, ok, tt.Length.OK)
+		}
+		p, s, ok := c.DecimalSize()
+		if p != tt.DecimalSize.Precision {
+			t.Errorf("(%d) got: %d, want: %d", i, p, tt.DecimalSize.Precision)
+		}
+		if s != tt.DecimalSize.Scale {
+			t.Errorf("(%d) got: %d, want: %d", i, s, tt.DecimalSize.Scale)
+		}
+		if ok != tt.DecimalSize.OK {
+			t.Errorf("(%d) got: %t, want: %t", i, ok, tt.DecimalSize.OK)
+		}
+		if c.ScanType() != tt.ScanType {
+			t.Errorf("(%d) got: %v, want: %v", i, c.ScanType(), tt.ScanType)
+		}
+	}
+}

vendor/src/github.com/lib/pq/ssl.go

@@ -15,7 +15,7 @@ import (
 func ssl(o values) func(net.Conn) net.Conn {
 	verifyCaOnly := false
 	tlsConf := tls.Config{}
-	switch mode := o.Get("sslmode"); mode {
+	switch mode := o["sslmode"]; mode {
 	// "require" is the default.
 	case "", "require":
 		// We must skip TLS's own verification since it requires full
@@ -23,15 +23,19 @@ func ssl(o values) func(net.Conn) net.Conn {
 		tlsConf.InsecureSkipVerify = true
 
 		// From http://www.postgresql.org/docs/current/static/libpq-ssl.html:
-		// Note: For backwards compatibility with earlier versions of PostgreSQL, if a
+		//
-		// root CA file exists, the behavior of sslmode=require will be the same as
+		// Note: For backwards compatibility with earlier versions of
-		// that of verify-ca, meaning the server certificate is validated against the
+		// PostgreSQL, if a root CA file exists, the behavior of
-		// CA. Relying on this behavior is discouraged, and applications that need
+		// sslmode=require will be the same as that of verify-ca, meaning the
-		// certificate validation should always use verify-ca or verify-full.
+		// server certificate is validated against the CA. Relying on this
-		if _, err := os.Stat(o.Get("sslrootcert")); err == nil {
+		// behavior is discouraged, and applications that need certificate
+		// validation should always use verify-ca or verify-full.
+		if sslrootcert, ok := o["sslrootcert"]; ok {
+			if _, err := os.Stat(sslrootcert); err == nil {
 				verifyCaOnly = true
 			} else {
-			o.Set("sslrootcert", "")
+				delete(o, "sslrootcert")
+			}
 		}
 	case "verify-ca":
 		// We must skip TLS's own verification since it requires full
@@ -39,7 +43,7 @@ func ssl(o values) func(net.Conn) net.Conn {
 		tlsConf.InsecureSkipVerify = true
 		verifyCaOnly = true
 	case "verify-full":
-		tlsConf.ServerName = o.Get("host")
+		tlsConf.ServerName = o["host"]
 	case "disable":
 		return nil
 	default:
@@ -64,37 +68,42 @@ func ssl(o values) func(net.Conn) net.Conn {
 // in the user's home directory. The configured files must exist and have
 // the correct permissions.
 func sslClientCertificates(tlsConf *tls.Config, o values) {
-	sslkey := o.Get("sslkey")
+	// user.Current() might fail when cross-compiling. We have to ignore the
-	sslcert := o.Get("sslcert")
+	// error and continue without home directory defaults, since we wouldn't
+	// know from where to load them.
+	user, _ := user.Current()
 
-	var cinfo, kinfo os.FileInfo
+	// In libpq, the client certificate is only loaded if the setting is not blank.
-	var err error
+	//
-
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1036-L1037
-	if sslcert != "" && sslkey != "" {
+	sslcert := o["sslcert"]
-		// Check that both files exist. Note that we don't do any more extensive
+	if len(sslcert) == 0 && user != nil {
-		// checks than this (such as checking that the paths aren't directories);
+		sslcert = filepath.Join(user.HomeDir, ".postgresql", "postgresql.crt")
-		// LoadX509KeyPair() will take care of the rest.
-		cinfo, err = os.Stat(sslcert)
-		if err != nil {
-			panic(err)
 	}
-
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1045
-		kinfo, err = os.Stat(sslkey)
+	if len(sslcert) == 0 {
-		if err != nil {
-			panic(err)
-		}
-	} else {
-		// Automatically find certificates from ~/.postgresql
-		sslcert, sslkey, cinfo, kinfo = sslHomeCertificates()
-
-		if cinfo == nil || kinfo == nil {
-			// No certificates to load
 		return
 	}
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1050:L1054
+	if _, err := os.Stat(sslcert); os.IsNotExist(err) {
+		return
+	} else if err != nil {
+		panic(err)
 	}
 
-	// The files must also have the correct permissions
+	// In libpq, the ssl key is only loaded if the setting is not blank.
-	sslCertificatePermissions(cinfo, kinfo)
+	//
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1123-L1222
+	sslkey := o["sslkey"]
+	if len(sslkey) == 0 && user != nil {
+		sslkey = filepath.Join(user.HomeDir, ".postgresql", "postgresql.key")
+	}
+
+	if len(sslkey) > 0 {
+		if err := sslKeyPermissions(sslkey); err != nil {
+			panic(err)
+		}
+	}
 
 	cert, err := tls.LoadX509KeyPair(sslcert, sslkey)
 	if err != nil {
@@ -105,7 +114,10 @@ func sslClientCertificates(tlsConf *tls.Config, o values) {
 
 // sslCertificateAuthority adds the RootCA specified in the "sslrootcert" setting.
 func sslCertificateAuthority(tlsConf *tls.Config, o values) {
-	if sslrootcert := o.Get("sslrootcert"); sslrootcert != "" {
+	// In libpq, the root certificate is only loaded if the setting is not blank.
+	//
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L950-L951
+	if sslrootcert := o["sslrootcert"]; len(sslrootcert) > 0 {
 		tlsConf.RootCAs = x509.NewCertPool()
 
 		cert, err := ioutil.ReadFile(sslrootcert)
@@ -113,41 +125,12 @@ func sslCertificateAuthority(tlsConf *tls.Config, o values) {
 			panic(err)
 		}
 
-		ok := tlsConf.RootCAs.AppendCertsFromPEM(cert)
+		if !tlsConf.RootCAs.AppendCertsFromPEM(cert) {
-		if !ok {
 			errorf("couldn't parse pem in sslrootcert")
 		}
 	}
 }
 
-// sslHomeCertificates returns the path and stats of certificates in the current
-// user's home directory.
-func sslHomeCertificates() (cert, key string, cinfo, kinfo os.FileInfo) {
-	user, err := user.Current()
-
-	if err != nil {
-		// user.Current() might fail when cross-compiling. We have to ignore the
-		// error and continue without client certificates, since we wouldn't know
-		// from where to load them.
-		return
-	}
-
-	cert = filepath.Join(user.HomeDir, ".postgresql", "postgresql.crt")
-	key = filepath.Join(user.HomeDir, ".postgresql", "postgresql.key")
-
-	cinfo, err = os.Stat(cert)
-	if err != nil {
-		cinfo = nil
-	}
-
-	kinfo, err = os.Stat(key)
-	if err != nil {
-		kinfo = nil
-	}
-
-	return
-}
-
 // sslVerifyCertificateAuthority carries out a TLS handshake to the server and
 // verifies the presented certificate against the CA, i.e. the one specified in
 // sslrootcert or the system CA if sslrootcert was not specified.

vendor/src/github.com/lib/pq/ssl_permissions.go

@@ -4,13 +4,17 @@ package pq
 
 import "os"
 
-// sslCertificatePermissions checks the permissions on user-supplied certificate
+// sslKeyPermissions checks the permissions on user-supplied ssl key files.
-// files. The key file should have very little access.
+// The key file should have very little access.
 //
 // libpq does not check key file permissions on Windows.
-func sslCertificatePermissions(cert, key os.FileInfo) {
+func sslKeyPermissions(sslkey string) error {
-	kmode := key.Mode()
+	info, err := os.Stat(sslkey)
-	if kmode != kmode&0600 {
+	if err != nil {
-		panic(ErrSSLKeyHasWorldPermissions)
+		return err
 	}
+	if info.Mode().Perm()&0077 != 0 {
+		return ErrSSLKeyHasWorldPermissions
+	}
+	return nil
 }

vendor/src/github.com/lib/pq/ssl_test.go

@@ -6,7 +6,6 @@ import (
 	_ "crypto/sha256"
 	"crypto/x509"
 	"database/sql"
-	"fmt"
 	"os"
 	"path/filepath"
 	"testing"
@@ -42,10 +41,13 @@ func openSSLConn(t *testing.T, conninfo string) (*sql.DB, error) {
 }
 
 func checkSSLSetup(t *testing.T, conninfo string) {
-	db, err := openSSLConn(t, conninfo)
+	_, err := openSSLConn(t, conninfo)
-	if err == nil {
+	if pge, ok := err.(*Error); ok {
-		db.Close()
+		if pge.Code.Name() != "invalid_authorization_specification" {
-		t.Fatalf("expected error with conninfo=%q", conninfo)
+			t.Fatalf("unexpected error code '%s'", pge.Code.Name())
+		}
+	} else {
+		t.Fatalf("expected %T, got %v", (*Error)(nil), err)
 	}
 }
 
@@ -150,120 +152,128 @@ func TestSSLVerifyCA(t *testing.T) {
 	checkSSLSetup(t, "sslmode=disable user=pqgossltest")
 
 	// Not OK according to the system CA
+	{
 		_, err := openSSLConn(t, "host=postgres sslmode=verify-ca user=pqgossltest")
-	if err == nil {
+		if _, ok := err.(x509.UnknownAuthorityError); !ok {
-		t.Fatal("expected error")
+			t.Fatalf("expected %T, got %#+v", x509.UnknownAuthorityError{}, err)
+		}
+	}
+
+	// Still not OK according to the system CA; empty sslrootcert is treated as unspecified.
+	{
+		_, err := openSSLConn(t, "host=postgres sslmode=verify-ca user=pqgossltest sslrootcert=''")
+		if _, ok := err.(x509.UnknownAuthorityError); !ok {
+			t.Fatalf("expected %T, got %#+v", x509.UnknownAuthorityError{}, err)
 		}
-	_, ok := err.(x509.UnknownAuthorityError)
-	if !ok {
-		t.Fatalf("expected x509.UnknownAuthorityError, got %#+v", err)
 	}
 
 	rootCertPath := filepath.Join(os.Getenv("PQSSLCERTTEST_PATH"), "root.crt")
 	rootCert := "sslrootcert=" + rootCertPath + " "
 	// No match on Common Name, but that's OK
-	_, err = openSSLConn(t, rootCert+"host=127.0.0.1 sslmode=verify-ca user=pqgossltest")
+	if _, err := openSSLConn(t, rootCert+"host=127.0.0.1 sslmode=verify-ca user=pqgossltest"); err != nil {
-	if err != nil {
 		t.Fatal(err)
 	}
 	// Everything OK
-	_, err = openSSLConn(t, rootCert+"host=postgres sslmode=verify-ca user=pqgossltest")
+	if _, err := openSSLConn(t, rootCert+"host=postgres sslmode=verify-ca user=pqgossltest"); err != nil {
-	if err != nil {
 		t.Fatal(err)
 	}
 }
 
-func getCertConninfo(t *testing.T, source string) string {
-	var sslkey string
-	var sslcert string
-
-	certpath := os.Getenv("PQSSLCERTTEST_PATH")
-
-	switch source {
-	case "missingkey":
-		sslkey = "/tmp/filedoesnotexist"
-		sslcert = filepath.Join(certpath, "postgresql.crt")
-	case "missingcert":
-		sslkey = filepath.Join(certpath, "postgresql.key")
-		sslcert = "/tmp/filedoesnotexist"
-	case "certtwice":
-		sslkey = filepath.Join(certpath, "postgresql.crt")
-		sslcert = filepath.Join(certpath, "postgresql.crt")
-	case "valid":
-		sslkey = filepath.Join(certpath, "postgresql.key")
-		sslcert = filepath.Join(certpath, "postgresql.crt")
-	default:
-		t.Fatalf("invalid source %q", source)
-	}
-	return fmt.Sprintf("sslmode=require user=pqgosslcert sslkey=%s sslcert=%s", sslkey, sslcert)
-}
-
 // Authenticate over SSL using client certificates
 func TestSSLClientCertificates(t *testing.T) {
 	maybeSkipSSLTests(t)
 	// Environment sanity check: should fail without SSL
 	checkSSLSetup(t, "sslmode=disable user=pqgossltest")
 
-	// Should also fail without a valid certificate
+	const baseinfo = "sslmode=require user=pqgosslcert"
-	db, err := openSSLConn(t, "sslmode=require user=pqgosslcert")
+
-	if err == nil {
+	// Certificate not specified, should fail
-		db.Close()
+	{
-		t.Fatal("expected error")
+		_, err := openSSLConn(t, baseinfo)
-	}
+		if pge, ok := err.(*Error); ok {
-	pge, ok := err.(*Error)
-	if !ok {
-		t.Fatal("expected pq.Error")
-	}
 			if pge.Code.Name() != "invalid_authorization_specification" {
-		t.Fatalf("unexpected error code %q", pge.Code.Name())
+				t.Fatalf("unexpected error code '%s'", pge.Code.Name())
+			}
+		} else {
+			t.Fatalf("expected %T, got %v", (*Error)(nil), err)
+		}
 	}
 
-	// Should work
+	// Empty certificate specified, should fail
-	db, err = openSSLConn(t, getCertConninfo(t, "valid"))
+	{
-	if err != nil {
+		_, err := openSSLConn(t, baseinfo+" sslcert=''")
-		t.Fatal(err)
+		if pge, ok := err.(*Error); ok {
+			if pge.Code.Name() != "invalid_authorization_specification" {
+				t.Fatalf("unexpected error code '%s'", pge.Code.Name())
 			}
+		} else {
+			t.Fatalf("expected %T, got %v", (*Error)(nil), err)
+		}
+	}
+
+	// Non-existent certificate specified, should fail
+	{
+		_, err := openSSLConn(t, baseinfo+" sslcert=/tmp/filedoesnotexist")
+		if pge, ok := err.(*Error); ok {
+			if pge.Code.Name() != "invalid_authorization_specification" {
+				t.Fatalf("unexpected error code '%s'", pge.Code.Name())
+			}
+		} else {
+			t.Fatalf("expected %T, got %v", (*Error)(nil), err)
+		}
+	}
+
+	certpath, ok := os.LookupEnv("PQSSLCERTTEST_PATH")
+	if !ok {
+		t.Fatalf("PQSSLCERTTEST_PATH not present in environment")
+	}
+
+	sslcert := filepath.Join(certpath, "postgresql.crt")
+
+	// Cert present, key not specified, should fail
+	{
+		_, err := openSSLConn(t, baseinfo+" sslcert="+sslcert)
+		if _, ok := err.(*os.PathError); !ok {
+			t.Fatalf("expected %T, got %#+v", (*os.PathError)(nil), err)
+		}
+	}
+
+	// Cert present, empty key specified, should fail
+	{
+		_, err := openSSLConn(t, baseinfo+" sslcert="+sslcert+" sslkey=''")
+		if _, ok := err.(*os.PathError); !ok {
+			t.Fatalf("expected %T, got %#+v", (*os.PathError)(nil), err)
+		}
+	}
+
+	// Cert present, non-existent key, should fail
+	{
+		_, err := openSSLConn(t, baseinfo+" sslcert="+sslcert+" sslkey=/tmp/filedoesnotexist")
+		if _, ok := err.(*os.PathError); !ok {
+			t.Fatalf("expected %T, got %#+v", (*os.PathError)(nil), err)
+		}
+	}
+
+	// Key has wrong permissions (passing the cert as the key), should fail
+	if _, err := openSSLConn(t, baseinfo+" sslcert="+sslcert+" sslkey="+sslcert); err != ErrSSLKeyHasWorldPermissions {
+		t.Fatalf("expected %s, got %#+v", ErrSSLKeyHasWorldPermissions, err)
+	}
+
+	sslkey := filepath.Join(certpath, "postgresql.key")
+
+	// Should work
+	if db, err := openSSLConn(t, baseinfo+" sslcert="+sslcert+" sslkey="+sslkey); err != nil {
+		t.Fatal(err)
+	} else {
 		rows, err := db.Query("SELECT 1")
 		if err != nil {
 			t.Fatal(err)
 		}
-	rows.Close()
+		if err := rows.Close(); err != nil {
+			t.Fatal(err)
+		}
+		if err := db.Close(); err != nil {
+			t.Fatal(err)
 		}
-
-// Test errors with ssl certificates
-func TestSSLClientCertificatesMissingFiles(t *testing.T) {
-	maybeSkipSSLTests(t)
-	// Environment sanity check: should fail without SSL
-	checkSSLSetup(t, "sslmode=disable user=pqgossltest")
-
-	// Key missing, should fail
-	_, err := openSSLConn(t, getCertConninfo(t, "missingkey"))
-	if err == nil {
-		t.Fatal("expected error")
-	}
-	// should be a PathError
-	_, ok := err.(*os.PathError)
-	if !ok {
-		t.Fatalf("expected PathError, got %#+v", err)
-	}
-
-	// Cert missing, should fail
-	_, err = openSSLConn(t, getCertConninfo(t, "missingcert"))
-	if err == nil {
-		t.Fatal("expected error")
-	}
-	// should be a PathError
-	_, ok = err.(*os.PathError)
-	if !ok {
-		t.Fatalf("expected PathError, got %#+v", err)
-	}
-
-	// Key has wrong permissions, should fail
-	_, err = openSSLConn(t, getCertConninfo(t, "certtwice"))
-	if err == nil {
-		t.Fatal("expected error")
-	}
-	if err != ErrSSLKeyHasWorldPermissions {
-		t.Fatalf("expected ErrSSLKeyHasWorldPermissions, got %#+v", err)
 	}
 }

vendor/src/github.com/lib/pq/ssl_windows.go

@@ -2,8 +2,8 @@
 
 package pq
 
-import "os"
+// sslKeyPermissions checks the permissions on user-supplied ssl key files.
-
+// The key file should have very little access.
-// sslCertificatePermissions checks the permissions on user-supplied certificate
+//
-// files. In libpq, this is a no-op on Windows.
+// libpq does not check key file permissions on Windows.
-func sslCertificatePermissions(cert, key os.FileInfo) {}
+func sslKeyPermissions(string) error { return nil }

vendor/src/github.com/lib/pq/uuid_test.go

@@ -33,7 +33,7 @@ func TestDecodeUUIDBackend(t *testing.T) {
 	db := openTestConn(t)
 	defer db.Close()
 
-	var s string = "a0ecc91d-a13f-4fe4-9fce-7e09777cc70a"
+	var s = "a0ecc91d-a13f-4fe4-9fce-7e09777cc70a"
 	var scanned interface{}
 
 	err := db.QueryRow(`SELECT $1::uuid`, s).Scan(&scanned)