Informer interface (#27)

* Informer interface

Author: n-r-w

README.md

@@ -95,7 +95,7 @@ func TestDatabase(t *testing.T) {
     configuration.
     */
 
-    pool := testdock.GetPgxPool(t, 
+    pool, _ := testdock.GetPgxPool(t, 
         testdock.DefaultPostgresDSN,
         testdock.WithMigrations("migrations", testdock.GooseMigrateFactoryPGX),        
     )
@@ -115,7 +115,7 @@ import (
 
 func TestMongoDB(t *testing.T) {        
     // Get a connection to a test database
-    db := testdock.GetMongoDatabase(t, testdock.DefaultMongoDSN,
+    db, _ := testdock.GetMongoDatabase(t, testdock.DefaultMongoDSN,
         testdock.WithMode(testdock.RunModeDocker),
         testdock.WithMigrations("migrations", testdock.GolangMigrateFactory),
     )
@@ -166,7 +166,7 @@ TestDock supports two popular migration tools:
 <https://github.com/pressly/goose>
 
 ```go
- db := GetPqConn(t,
+ db, _ := GetPqConn(t,
     "postgres://postgres:secret@127.0.0.1:5432/postgres?sslmode=disable",
     testdock.WithMigrations("migrations/pg/goose", testdock.GooseMigrateFactoryPQ),
     testdock.WithDockerImage("17.2"),
@@ -178,7 +178,7 @@ TestDock supports two popular migration tools:
 <https://github.com/golang-migrate/migrate>
 
 ```go
-db := GetMongoDatabase(t,
+db, _ := GetMongoDatabase(t,
     testdock.DefaultMongoDSN,
     WithDockerRepository("mongo"),
     WithDockerImage("6.0.20"),

db.go

@@ -11,6 +11,18 @@ import (
 	"github.com/cenkalti/backoff/v5"
 )
 
+// Informer interface for database information.
+type Informer interface {
+	// DSN returns the real database connection string.
+	DSN() string
+	// Host returns the host of the database server.
+	Host() string
+	// Port returns the port of the database server.
+	Port() int
+	// DatabaseName returns the database name for testing.
+	DatabaseName() string
+}
+
 const (
 	// DefaultRetryTimeout is the default retry timeout.
 	DefaultRetryTimeout = time.Second * 3
@@ -210,3 +222,23 @@ func (d *testDB) retryConnect(info string, op func() error) error {
 
 	return nil
 }
+
+// DSN returns the real database connection string.
+func (d *testDB) DSN() string {
+	return d.url.replaceDatabase(d.databaseName).string(false)
+}
+
+// Host returns the database host.
+func (d *testDB) Host() string {
+	return d.url.Host
+}
+
+// Port returns the database port.
+func (d *testDB) Port() int {
+	return d.url.Port
+}
+
+// DatabaseName returns the database name for testing.
+func (d *testDB) DatabaseName() string {
+	return d.databaseName
+}

mongodb.go

@@ -13,7 +13,7 @@ import (
 const mongoDriverName = "mongodb"
 
 // GetMongoDatabase  initializes a test MongoDB database, applies migrations, and returns a database connection.
-func GetMongoDatabase(tb testing.TB, dsn string, opt ...Option) *mongo.Database {
+func GetMongoDatabase(tb testing.TB, dsn string, opt ...Option) (*mongo.Database, Informer) {
 	tb.Helper()
 
 	url, err := parseURL(dsn)
@@ -42,7 +42,7 @@ func GetMongoDatabase(tb testing.TB, dsn string, opt ...Option) *mongo.Database
 
 	tb.Cleanup(func() { _ = client.Disconnect(context.Background()) })
 
-	return client.Database(tDB.databaseName)
+	return client.Database(tDB.databaseName), tDB
 }
 
 // connectDB connects to MongoDB with retries

mongodb_test.go

@@ -14,13 +14,15 @@ func TestMongoDB(t *testing.T) {
 	ctx := context.Background()
 
 	// Create test database and return a MongoDB client
-	db := GetMongoDatabase(t,
+	db, informer := GetMongoDatabase(t,
 		DefaultMongoDSN,
 		WithDockerRepository("mongo"),
 		WithDockerImage("6.0.20"),
 		WithMigrations("migrations/mongodb", GolangMigrateFactory),
 	)
 
+	checkInformer(t, DefaultMongoDSN, informer)
+
 	// Test collection
 	collection := db.Collection("test_collection")
 

mysql.go

@@ -10,7 +10,7 @@ import (
 
 // GetMySQLConn inits a test mysql database, applies migrations.
 // Use user root for docker test database.
-func GetMySQLConn(tb testing.TB, dsn string, opt ...Option) *sql.DB {
+func GetMySQLConn(tb testing.TB, dsn string, opt ...Option) (*sql.DB, Informer) {
 	tb.Helper()
 
 	url, err := parseURL(dsn)

mysql_test.go

@@ -9,13 +9,15 @@ import (
 func Test_MySQLDB(t *testing.T) {
 	t.Parallel()
 
-	db := GetMySQLConn(t,
+	db, informer := GetMySQLConn(t,
 		DefaultMySQLDSN,
 		WithMigrations("migrations/pg/goose", GooseMigrateFactoryMySQL),
 		WithRetryTimeout(time.Second*5),
 		WithTotalRetryDuration(time.Second*60), //nolint:mnd // for Docker 30s not enough
 	)
 
+	checkInformer(t, DefaultMySQLDSN, informer)
+
 	testSQLHelper(t, db)
 }
 

postgresql.go

@@ -14,7 +14,7 @@ import (
 
 // GetPgxPool inits a test postgresql (pgx driver) database, applies migrations,
 // and returns pgx connection pool to the database.
-func GetPgxPool(tb testing.TB, dsn string, opt ...Option) *pgxpool.Pool {
+func GetPgxPool(tb testing.TB, dsn string, opt ...Option) (*pgxpool.Pool, Informer) {
 	tb.Helper()
 
 	tDB := newTDB(tb, "pgx", dsn, getPostgresOptions(tb, dsn, opt...))
@@ -26,12 +26,12 @@ func GetPgxPool(tb testing.TB, dsn string, opt ...Option) *pgxpool.Pool {
 
 	tb.Cleanup(func() { db.Close() })
 
-	return db
+	return db, tDB
 }
 
 // GetPqConn inits a test postgresql (pq driver) database, applies migrations,
 // and returns sql connection to the database.
-func GetPqConn(tb testing.TB, dsn string, opt ...Option) *sql.DB {
+func GetPqConn(tb testing.TB, dsn string, opt ...Option) (*sql.DB, Informer) {
 	tb.Helper()
 
 	tDB := newTDB(tb, "postgres", dsn, getPostgresOptions(tb, dsn, opt...))
@@ -43,7 +43,7 @@ func GetPqConn(tb testing.TB, dsn string, opt ...Option) *sql.DB {
 
 	tb.Cleanup(func() { _ = db.Close() })
 
-	return db
+	return db, tDB
 }
 
 // connectPgxDB connects to the database with retries using pgx.

postgresql_test.go

@@ -13,32 +13,36 @@ const testPostgresImage = "17.2"
 func Test_PgxGooseDB(t *testing.T) {
 	t.Parallel()
 
-	db := GetPgxPool(t,
+	db, informer := GetPgxPool(t,
 		DefaultPostgresDSN,
 		WithMigrations("migrations/pg/goose", GooseMigrateFactoryPGX),
 		WithDockerImage(testPostgresImage),
 	)
 
+	checkInformer(t, DefaultPostgresDSN, informer)
+
 	testPgxHelper(t, db)
 }
 
 func Test_PgxGomigrateDB(t *testing.T) {
 	t.Parallel()
 
-	db := GetPgxPool(t,
+	db, informer := GetPgxPool(t,
 		DefaultPostgresDSN,
 		WithMigrations("migrations/pg/gomigrate", GolangMigrateFactory),
 		WithDockerImage(testPostgresImage),
 		WithMode(RunModeDocker), // force run in docker
 	)
 
+	checkInformer(t, DefaultPostgresDSN, informer)
+
 	testPgxHelper(t, db)
 }
 
 func Test_LibPGDB(t *testing.T) {
 	t.Parallel()
 
-	db := GetPqConn(t,
+	db, _ := GetPqConn(t,
 		DefaultPostgresDSN,
 		WithMigrations("migrations/pg/goose", GooseMigrateFactoryPQ),
 		WithDockerImage(testPostgresImage),

prepare_test.go

@@ -0,0 +1,24 @@
+package testdock
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func checkInformer(t *testing.T, defaultDSN string, informer Informer) {
+	t.Helper()
+
+	defaultURL, err := parseURL(defaultDSN)
+	require.NoError(t, err)
+
+	url, err := parseURL(informer.DSN())
+	require.NoError(t, err)
+
+	require.NotEqual(t, defaultURL.Database, url.Database)
+	require.NotEqual(t, defaultURL.Database, informer.DatabaseName())
+	require.Equal(t, defaultURL.User, url.User)
+	require.Equal(t, defaultURL.Password, url.Password)
+	require.Equal(t, defaultURL.Host, informer.Host())
+	require.Equal(t, url.Port, informer.Port())
+}

sql.go

@@ -9,7 +9,7 @@ import (
 // GetSQLConn inits a test database, applies migrations, and returns sql connection to the database.
 // driver: https://go.dev/wiki/SQLDrivers.
 // Do not forget to import corresponding driver package.
-func GetSQLConn(tb testing.TB, driver, dsn string, opt ...Option) *sql.DB {
+func GetSQLConn(tb testing.TB, driver, dsn string, opt ...Option) (*sql.DB, Informer) {
 	tb.Helper()
 
 	tDB := newTDB(tb, driver, dsn, opt)
@@ -19,9 +19,11 @@ func GetSQLConn(tb testing.TB, driver, dsn string, opt ...Option) *sql.DB {
 		tDB.logger.Fatalf("%v", err)
 	}
 
+	
+
 	tb.Cleanup(func() { _ = db.Close() })
 
-	return db
+	return db, tDB
 }
 
 // connectSQLDB connects to the database with retries using database/sql.