Add test infrastructure code for dendrite unit/integ tests (#2331)

* Add test infrastructure code for dendrite unit/integ tests

Start re-enabling some syncapi storage tests in the process.

* Linting

* Add postgres service to unit tests

* dendrite not syncv3

* Skip test which doesn't work

* Linting

* Add `jetstream.PrepareForTests`

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>

test/db.go

@@ -0,0 +1,127 @@
+// 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 (
+	"database/sql"
+	"fmt"
+	"os"
+	"os/exec"
+	"os/user"
+	"testing"
+)
+
+type DBType int
+
+var DBTypeSQLite DBType = 1
+var DBTypePostgres DBType = 2
+
+var Quiet = false
+
+func createLocalDB(dbName string) 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)
+	}
+	return dbName
+}
+
+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 {
+		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()
+	}
+	dbName := os.Getenv("POSTGRES_DB")
+	if dbName == "" {
+		dbName = createLocalDB("dendrite_test")
+	}
+	connStr = fmt.Sprintf(
+		"user=%s dbname=%s sslmode=disable",
+		user, dbName,
+	)
+	// 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)
+	}
+
+	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) {
+			testFn(tt, dbt)
+		})
+	}
+}