dendrite/clientapi/auth/storage/accounts/filter_table.go

108 lines
3.1 KiB
Go

// Copyright 2017 Jan Christian Grünhage
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package accounts
import (
"context"
"database/sql"
"github.com/matrix-org/gomatrixserverlib"
)
const filterSchema = `
-- Stores data about filters
CREATE TABLE IF NOT EXISTS account_filter (
-- The filter
filter TEXT NOT NULL,
-- The ID
id SERIAL UNIQUE,
-- The localpart of the Matrix user ID associated to this filter
localpart TEXT NOT NULL,
PRIMARY KEY(id, localpart)
);
CREATE INDEX IF NOT EXISTS account_filter_localpart ON account_filter(localpart);
`
const selectFilterSQL = "" +
"SELECT filter FROM account_filter WHERE localpart = $1 AND id = $2"
const selectFilterIDByContentSQL = "" +
"SELECT id FROM account_filter WHERE localpart = $1 AND filter = $2"
const insertFilterSQL = "" +
"INSERT INTO account_filter (filter, id, localpart) VALUES ($1, DEFAULT, $2) RETURNING id"
type filterStatements struct {
selectFilterStmt *sql.Stmt
selectFilterIDByContentStmt *sql.Stmt
insertFilterStmt *sql.Stmt
}
func (s *filterStatements) prepare(db *sql.DB) (err error) {
_, err = db.Exec(filterSchema)
if err != nil {
return
}
if s.selectFilterStmt, err = db.Prepare(selectFilterSQL); err != nil {
return
}
if s.selectFilterIDByContentStmt, err = db.Prepare(selectFilterIDByContentSQL); err != nil {
return
}
if s.insertFilterStmt, err = db.Prepare(insertFilterSQL); err != nil {
return
}
return
}
func (s *filterStatements) selectFilter(
ctx context.Context, localpart string, filterID string,
) (filter []byte, err error) {
err = s.selectFilterStmt.QueryRowContext(ctx, localpart, filterID).Scan(&filter)
return
}
func (s *filterStatements) insertFilter(
ctx context.Context, filter []byte, localpart string,
) (filterID string, err error) {
var existingFilterID string
// This can result in a race condition when two clients try to insert the
// same filter and localpart at the same time, however this is not a
// problem as both calls will result in the same filterID
filterJSON, err := gomatrixserverlib.CanonicalJSON(filter)
if err != nil {
return "", err
}
// Check if filter already exists in the database
err = s.selectFilterIDByContentStmt.QueryRowContext(ctx,
localpart, filterJSON).Scan(&existingFilterID)
if err != nil && err != sql.ErrNoRows {
return "", err
}
// If it does, return the existing ID
if existingFilterID != "" {
return existingFilterID, err
}
// Otherwise insert the filter and return the new ID
err = s.insertFilterStmt.QueryRowContext(ctx, filterJSON, localpart).
Scan(&filterID)
return
}