dendrite/common/httpapi.go

182 lines
6.3 KiB
Go

package common
import (
"net/http"
"time"
"github.com/matrix-org/dendrite/clientapi/auth"
"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
"github.com/matrix-org/dendrite/common/config"
"github.com/matrix-org/gomatrixserverlib"
"github.com/matrix-org/util"
opentracing "github.com/opentracing/opentracing-go"
"github.com/opentracing/opentracing-go/ext"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promauto"
"github.com/prometheus/client_golang/prometheus/promhttp"
"github.com/sirupsen/logrus"
)
// BasicAuth is used for authorization on /metrics handlers
type BasicAuth struct {
Username string `yaml:"username"`
Password string `yaml:"password"`
}
// MakeAuthAPI turns a util.JSONRequestHandler function into an http.Handler which authenticates the request.
func MakeAuthAPI(
metricsName string, data auth.Data,
f func(*http.Request, *authtypes.Device) util.JSONResponse,
) http.Handler {
h := func(req *http.Request) util.JSONResponse {
device, err := auth.VerifyUserFromRequest(req, data)
if err != nil {
return *err
}
// add the user ID to the logger
logger := util.GetLogger((req.Context()))
logger = logger.WithField("user_id", device.UserID)
req = req.WithContext(util.ContextWithLogger(req.Context(), logger))
return f(req, device)
}
return MakeExternalAPI(metricsName, h)
}
// MakeExternalAPI turns a util.JSONRequestHandler function into an http.Handler.
// This is used for APIs that are called from the internet.
func MakeExternalAPI(metricsName string, f func(*http.Request) util.JSONResponse) http.Handler {
h := util.MakeJSONAPI(util.NewJSONRequestHandler(f))
withSpan := func(w http.ResponseWriter, req *http.Request) {
span := opentracing.StartSpan(metricsName)
defer span.Finish()
req = req.WithContext(opentracing.ContextWithSpan(req.Context(), span))
h.ServeHTTP(w, req)
}
return http.HandlerFunc(withSpan)
}
// MakeHTMLAPI adds Span metrics to the HTML Handler function
// This is used to serve HTML alongside JSON error messages
func MakeHTMLAPI(metricsName string, f func(http.ResponseWriter, *http.Request) *util.JSONResponse) http.Handler {
withSpan := func(w http.ResponseWriter, req *http.Request) {
span := opentracing.StartSpan(metricsName)
defer span.Finish()
req = req.WithContext(opentracing.ContextWithSpan(req.Context(), span))
if err := f(w, req); err != nil {
h := util.MakeJSONAPI(util.NewJSONRequestHandler(func(req *http.Request) util.JSONResponse {
return *err
}))
h.ServeHTTP(w, req)
}
}
return promhttp.InstrumentHandlerCounter(
promauto.NewCounterVec(
prometheus.CounterOpts{
Name: metricsName,
Help: "Total number of http requests for HTML resources",
},
[]string{"code"},
),
http.HandlerFunc(withSpan),
)
}
// MakeInternalAPI turns a util.JSONRequestHandler function into an http.Handler.
// This is used for APIs that are internal to dendrite.
// If we are passed a tracing context in the request headers then we use that
// as the parent of any tracing spans we create.
func MakeInternalAPI(metricsName string, f func(*http.Request) util.JSONResponse) http.Handler {
h := util.MakeJSONAPI(util.NewJSONRequestHandler(f))
withSpan := func(w http.ResponseWriter, req *http.Request) {
carrier := opentracing.HTTPHeadersCarrier(req.Header)
tracer := opentracing.GlobalTracer()
clientContext, err := tracer.Extract(opentracing.HTTPHeaders, carrier)
var span opentracing.Span
if err == nil {
// Default to a span without RPC context.
span = tracer.StartSpan(metricsName)
} else {
// Set the RPC context.
span = tracer.StartSpan(metricsName, ext.RPCServerOption(clientContext))
}
defer span.Finish()
req = req.WithContext(opentracing.ContextWithSpan(req.Context(), span))
h.ServeHTTP(w, req)
}
return http.HandlerFunc(withSpan)
}
// MakeFedAPI makes an http.Handler that checks matrix federation authentication.
func MakeFedAPI(
metricsName string,
serverName gomatrixserverlib.ServerName,
keyRing gomatrixserverlib.KeyRing,
f func(*http.Request, *gomatrixserverlib.FederationRequest) util.JSONResponse,
) http.Handler {
h := func(req *http.Request) util.JSONResponse {
fedReq, errResp := gomatrixserverlib.VerifyHTTPRequest(
req, time.Now(), serverName, keyRing,
)
if fedReq == nil {
return errResp
}
return f(req, fedReq)
}
return MakeExternalAPI(metricsName, h)
}
// SetupHTTPAPI registers an HTTP API mux under /api and sets up a metrics
// listener.
func SetupHTTPAPI(servMux *http.ServeMux, apiMux http.Handler, cfg *config.Dendrite) {
if cfg.Metrics.Enabled {
servMux.Handle("/metrics", WrapHandlerInBasicAuth(promhttp.Handler(), cfg.Metrics.BasicAuth))
}
servMux.Handle("/api/", http.StripPrefix("/api", apiMux))
}
// WrapHandlerInBasicAuth adds basic auth to a handler. Only used for /metrics
func WrapHandlerInBasicAuth(h http.Handler, b BasicAuth) http.HandlerFunc {
if b.Username == "" || b.Password == "" {
logrus.Warn("Metrics are exposed without protection. Make sure you set up protection at proxy level.")
}
return func(w http.ResponseWriter, r *http.Request) {
// Serve without authorization if either Username or Password is unset
if b.Username == "" || b.Password == "" {
h.ServeHTTP(w, r)
return
}
user, pass, ok := r.BasicAuth()
if !ok || user != b.Username || pass != b.Password {
http.Error(w, http.StatusText(http.StatusForbidden), http.StatusForbidden)
return
}
h.ServeHTTP(w, r)
}
}
// WrapHandlerInCORS adds CORS headers to all responses, including all error
// responses.
// Handles OPTIONS requests directly.
func WrapHandlerInCORS(h http.Handler) http.HandlerFunc {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Access-Control-Allow-Origin", "*")
w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
w.Header().Set("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Authorization")
if r.Method == http.MethodOptions && r.Header.Get("Access-Control-Request-Method") != "" {
// Its easiest just to always return a 200 OK for everything. Whether
// this is technically correct or not is a question, but in the end this
// is what a lot of other people do (including synapse) and the clients
// are perfectly happy with it.
w.WriteHeader(http.StatusOK)
} else {
h.ServeHTTP(w, r)
}
})
}