dendrite/test/db.go
kegsay ea92f80c12
Add database namespacing for unit tests (#2340)
* Add database namespacing for unit tests

Background: Running `go test ./...` will run tests in different packages concurrently.
This can be stopped or limited by using `-p 1` (no concurrency). We want concurrency,
but this causes problems when running Postgres DBs in CI. The problem is that, in CI,
we have 1x postgres server exposing 1x postgres DB, which we wipe clean at the end of
each test via `defer close()`. When tests run concurrently, calls to `close()` will
delete data/tables which other tests are currently using, causing havoc.

Fix this by:
 - Creating a database per package.
 - Namespacing the database name by a hash of the current working directory (the directory containing those `_test.go` files)

This is exactly what SQLite does, quite unintentionally, via the use of `file:dendrite_test.db`,
which dumps the file into the current working directory which is the package running the tests,
hence deleting the file is safe when running concurrently.

* Linting

* Don't create the database in a txn

* dupe db is not an error
2022-04-11 10:23:01 +01:00

171 lines
5 KiB
Go

// Copyright 2022 The Matrix.org Foundation C.I.C.
//
// 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 test
import (
"crypto/sha256"
"database/sql"
"encoding/hex"
"fmt"
"os"
"os/exec"
"os/user"
"testing"
"github.com/lib/pq"
)
type DBType int
var DBTypeSQLite DBType = 1
var DBTypePostgres DBType = 2
var Quiet = false
func createLocalDB(dbName string) {
if !Quiet {
fmt.Println("Note: tests require a postgres install accessible to the current user")
}
createDB := exec.Command("createdb", dbName)
if !Quiet {
createDB.Stdout = os.Stdout
createDB.Stderr = os.Stderr
}
err := createDB.Run()
if err != nil && !Quiet {
fmt.Println("createLocalDB returned error:", err)
}
}
func createRemoteDB(t *testing.T, dbName, user, connStr string) {
db, err := sql.Open("postgres", connStr+" dbname=postgres")
if err != nil {
t.Fatalf("failed to open postgres conn with connstr=%s : %s", connStr, err)
}
_, err = db.Exec(fmt.Sprintf(`CREATE DATABASE %s;`, dbName))
if err != nil {
pqErr, ok := err.(*pq.Error)
if !ok {
t.Fatalf("failed to CREATE DATABASE: %s", err)
}
// we ignore duplicate database error as we expect this
if pqErr.Code != "42P04" {
t.Fatalf("failed to CREATE DATABASE with code=%s msg=%s", pqErr.Code, pqErr.Message)
}
}
_, err = db.Exec(fmt.Sprintf(`GRANT ALL PRIVILEGES ON DATABASE %s TO %s`, dbName, user))
if err != nil {
t.Fatalf("failed to GRANT: %s", err)
}
_ = db.Close()
}
func currentUser() string {
user, err := user.Current()
if err != nil {
if !Quiet {
fmt.Println("cannot get current user: ", err)
}
os.Exit(2)
}
return user.Username
}
// Prepare a sqlite or postgres connection string for testing.
// Returns the connection string to use and a close function which must be called when the test finishes.
// Calling this function twice will return the same database, which will have data from previous tests
// unless close() is called.
// TODO: namespace for concurrent package tests
func PrepareDBConnectionString(t *testing.T, dbType DBType) (connStr string, close func()) {
if dbType == DBTypeSQLite {
// this will be made in the current working directory which namespaces concurrent package runs correctly
dbname := "dendrite_test.db"
return fmt.Sprintf("file:%s", dbname), func() {
err := os.Remove(dbname)
if err != nil {
t.Fatalf("failed to cleanup sqlite db '%s': %s", dbname, err)
}
}
}
// Required vars: user and db
// We'll try to infer from the local env if they are missing
user := os.Getenv("POSTGRES_USER")
if user == "" {
user = currentUser()
}
connStr = fmt.Sprintf(
"user=%s sslmode=disable",
user,
)
// optional vars, used in CI
password := os.Getenv("POSTGRES_PASSWORD")
if password != "" {
connStr += fmt.Sprintf(" password=%s", password)
}
host := os.Getenv("POSTGRES_HOST")
if host != "" {
connStr += fmt.Sprintf(" host=%s", host)
}
// superuser database
postgresDB := os.Getenv("POSTGRES_DB")
// we cannot use 'dendrite_test' here else 2x concurrently running packages will try to use the same db.
// instead, hash the current working directory, snaffle the first 16 bytes and append that to dendrite_test
// and use that as the unique db name. We do this because packages are per-directory hence by hashing the
// working (test) directory we ensure we get a consistent hash and don't hash against concurrent packages.
wd, err := os.Getwd()
if err != nil {
t.Fatalf("cannot get working directory: %s", err)
}
hash := sha256.Sum256([]byte(wd))
dbName := fmt.Sprintf("dendrite_test_%s", hex.EncodeToString(hash[:16]))
if postgresDB == "" { // local server, use createdb
createLocalDB(dbName)
} else { // remote server, shell into the postgres user and CREATE DATABASE
createRemoteDB(t, dbName, user, connStr)
}
connStr += fmt.Sprintf(" dbname=%s", dbName)
return connStr, func() {
// Drop all tables on the database to get a fresh instance
db, err := sql.Open("postgres", connStr)
if err != nil {
t.Fatalf("failed to connect to postgres db '%s': %s", connStr, err)
}
_, err = db.Exec(`DROP SCHEMA public CASCADE;
CREATE SCHEMA public;`)
if err != nil {
t.Fatalf("failed to cleanup postgres db '%s': %s", connStr, err)
}
_ = db.Close()
}
}
// Creates subtests with each known DBType
func WithAllDatabases(t *testing.T, testFn func(t *testing.T, db DBType)) {
dbs := map[string]DBType{
"postgres": DBTypePostgres,
"sqlite": DBTypeSQLite,
}
for dbName, dbType := range dbs {
dbt := dbType
t.Run(dbName, func(tt *testing.T) {
tt.Parallel()
testFn(tt, dbt)
})
}
}