Add a MySQL provider

.github/workflows/ci.yml

@@ -35,6 +35,17 @@ jobs:
           --health-retries 5
         ports:
           - 5432:5432
+      mysql:
+        image: mysql:8.4
+        env:
+          MYSQL_ROOT_PASSWORD: root
+        options: >-
+          --health-cmd "mysql -uroot -proot -e 'SELECT 1'"
+          --health-interval 5s
+          --health-timeout 5s
+          --health-retries 12
+        ports:
+          - 3306:3306
 
     steps:
       - uses: actions/checkout@08eba0b27e820071cde6df949e0beb9ba4906955

Makefile

@@ -58,6 +58,9 @@ POSTGRES_PORT := 5432
 POSTGRES_USER := postgres
 POSTGRES_PASSWORD := postgres
 POSTGRES_DB := testdb
+MYSQL_SERVICE := test-mysql
+MYSQL_USER := root
+MYSQL_PASSWORD := root
 
 .PHONY: check_pgcli
 check_pgcli:
@@ -83,12 +86,30 @@ define wait_for_postgres
 	echo "✅ Postgres is ready!"
 endef
 
+# mysqladmin ping answers before the server accepts SQL, so wait for a query.
+define wait_for_mysql
+	@echo "Waiting for MySQL to be ready..."
+	@attempts=0; \
+	while ! docker compose -f $(1) exec -T $(2) mysql -u$(3) -p$(4) -e 'SELECT 1' >/dev/null 2>&1; do \
+		attempts=$$((attempts+1)); \
+		if [ $$attempts -gt 60 ]; then \
+			echo "❌ MySQL failed to become ready after 60 seconds"; \
+			echo "Try 'make $(5)' for a fresh start"; \
+			exit 1; \
+		fi; \
+		echo "⏳ Waiting... ($$attempts/60)"; \
+		sleep 1; \
+	done; \
+	echo "✅ MySQL is ready!"
+endef
+
 ## test/db/start: Start PostgreSQL test database
 .PHONY: test/db/start
 test/db/start:
 	@echo 'Starting test database...'
 	docker compose -f $(POSTGRES_COMPOSE_FILE) up -d
 	$(call wait_for_postgres,$(POSTGRES_COMPOSE_FILE),$(POSTGRES_SERVICE),$(POSTGRES_USER),$(POSTGRES_DB),test/db/restart)
+	$(call wait_for_mysql,$(POSTGRES_COMPOSE_FILE),$(MYSQL_SERVICE),$(MYSQL_USER),$(MYSQL_PASSWORD),test/db/restart)
 
 ## test/db/stop: Stop PostgreSQL test database
 .PHONY: test/db/stop
@@ -117,8 +138,9 @@ test/db/clean:
 test/db/restart: test/db/clean
 	@echo "Starting fresh Postgres instance..."
 	docker compose -f $(POSTGRES_COMPOSE_FILE) build --force-rm --no-cache $(POSTGRES_SERVICE)
-	docker compose -f $(POSTGRES_COMPOSE_FILE) up -d $(POSTGRES_SERVICE)
+	docker compose -f $(POSTGRES_COMPOSE_FILE) up -d
 	$(call wait_for_postgres,$(POSTGRES_COMPOSE_FILE),$(POSTGRES_SERVICE),$(POSTGRES_USER),$(POSTGRES_DB),test/db/restart)
+	$(call wait_for_mysql,$(POSTGRES_COMPOSE_FILE),$(MYSQL_SERVICE),$(MYSQL_USER),$(MYSQL_PASSWORD),test/db/restart)
 
 ## test/db/psql: Connect to Postgres database
 .PHONY: test/db/psql

docker-compose.test.yml

@@ -22,3 +22,24 @@ services:
       - "full_page_writes=off"
       - "-c"
       - "max_connections=300"
+
+  test-mysql:
+    image: mysql:8.4
+    environment:
+      MYSQL_ROOT_PASSWORD: root
+    ports:
+      - "3306:3306"
+    healthcheck:
+      test: ["CMD", "mysql", "-uroot", "-proot", "-e", "SELECT 1"]
+      interval: 5s
+      timeout: 3s
+      retries: 12
+    # Durability off, as for Postgres above: this server only ever holds
+    # throwaway test databases, and these settings make every DDL and drop
+    # markedly faster.
+    command:
+      - "--innodb-flush-log-at-trx-commit=0"
+      - "--sync-binlog=0"
+      - "--skip-log-bin"
+      - "--innodb-doublewrite=0"
+      - "--innodb-flush-method=O_DIRECT_NO_FSYNC"

go.mod

@@ -3,12 +3,14 @@ module github.com/bashhack/testdb
 go 1.27.0
 
 require (
+	github.com/go-sql-driver/mysql v1.10.1
 	github.com/jackc/pgx/v5 v5.11.0
 	gorm.io/driver/postgres v1.6.0
 	gorm.io/gorm v1.31.0
 )
 
 require (
+	filippo.io/edwards25519 v1.2.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
 	github.com/jackc/puddle/v2 v2.2.2 // indirect

go.sum

@@ -1,6 +1,10 @@
+filippo.io/edwards25519 v1.2.0 h1:crnVqOiS4jqYleHd9vaKZ+HKtHfllngJIiOpNpoJsjo=
+filippo.io/edwards25519 v1.2.0/go.mod h1:xzAOLCNug/yB62zG1bQ8uziwrIqIuxhctzJT18Q77mc=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-sql-driver/mysql v1.10.1 h1:arlSnNLq6a5yxGxV7qg9lF4j0C+KwD6NbQyKr9QL6ME=
+github.com/go-sql-driver/mysql v1.10.1/go.mod h1:M+cqaI7+xxXGG9swrdeUIoPG3Y3KCkF0pZej+SK+nWk=
 github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
 github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
 github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=

go.work.sum

@@ -1,4 +1,8 @@
+filippo.io/edwards25519 v1.2.0 h1:crnVqOiS4jqYleHd9vaKZ+HKtHfllngJIiOpNpoJsjo=
+filippo.io/edwards25519 v1.2.0/go.mod h1:xzAOLCNug/yB62zG1bQ8uziwrIqIuxhctzJT18Q77mc=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/go-sql-driver/mysql v1.10.1 h1:arlSnNLq6a5yxGxV7qg9lF4j0C+KwD6NbQyKr9QL6ME=
+github.com/go-sql-driver/mysql v1.10.1/go.mod h1:M+cqaI7+xxXGG9swrdeUIoPG3Y3KCkF0pZej+SK+nWk=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=

helpers.go

@@ -0,0 +1,59 @@
+package testdb
+
+import (
+	"io"
+	"testing"
+)
+
+// RunConfiguredMigrations and RegisterCleanup are what every database
+// package's Setup and New are built from, so all providers behave the same
+// way around a test: migrations run under the test's context, cleanup closes
+// the entity before dropping, and KeepOnFailure means the same thing
+// everywhere.
+
+// RunConfiguredMigrations runs the Migrator set with WithMigrator, if any.
+// On failure it drops the database (or keeps it, under KeepOnFailure, since
+// a half-applied migration is exactly what one wants to look at) and calls
+// t.Fatalf, so it does not return. callerName is the function the test
+// called, for the message.
+func RunConfiguredMigrations(t testing.TB, db *TestDatabase, callerName string) {
+	t.Helper()
+	if db.Config().Migrator == nil {
+		return
+	}
+	err := db.RunMigrations(ContextOf(t))
+	if err == nil {
+		return
+	}
+	if db.Config().KeepOnFailure {
+		db.Keep()
+	}
+	if closeErr := db.Close(); closeErr != nil {
+		t.Logf("Warning: failed to close database after migration error: %v", closeErr)
+	}
+	t.Fatalf("%s: migrations failed: %v", callerName, err)
+}
+
+// RegisterCleanup arranges for the database to go away when the test ends:
+// the entity is closed first if it implements io.Closer, then Close drops
+// the database. With KeepOnFailure, a failed test's database is kept
+// instead (see Keep).
+func RegisterCleanup(t testing.TB, db *TestDatabase) {
+	t.Cleanup(func() {
+		if entity := db.Entity(); entity != nil {
+			if closer, ok := entity.(io.Closer); ok {
+				if err := closer.Close(); err != nil {
+					t.Logf("Warning: failed to close entity: %v", err)
+				}
+			}
+		}
+
+		if db.Config().KeepOnFailure && t.Failed() {
+			db.Keep()
+		}
+
+		if err := db.Close(); err != nil {
+			t.Errorf("testdb cleanup failed: %v", err)
+		}
+	})
+}

keep_test.go

@@ -30,6 +30,11 @@ func (p *countingProvider) Cleanup(ctx context.Context) error {
 	return p.mockProvider.Cleanup(ctx)
 }
 
+// InspectCommand stands in for a database client invocation.
+func (p *countingProvider) InspectCommand(dsn string) string {
+	return "connect-with " + dsn
+}
+
 func TestCloseDropsByDefault(t *testing.T) {
 	provider := &countingProvider{}
 	db, err := New(t, provider, nil)
@@ -74,8 +79,29 @@ func TestKeepLeavesDatabaseAndLogsHowToConnect(t *testing.T) {
 	if kept == "" {
 		t.Fatalf("expected a 'kept database' log line, got %v", spy.logs)
 	}
-	if !strings.Contains(kept, db.Name()) || !strings.Contains(kept, "psql") || !strings.Contains(kept, db.DSN()) {
-		t.Errorf("kept-database log should name the database and give a psql command with its DSN, got: %s", kept)
+	if !strings.Contains(kept, db.Name()) || !strings.Contains(kept, "connect-with "+db.DSN()) {
+		t.Errorf("kept-database log should name the database and give the provider's connect command, got: %s", kept)
+	}
+}
+
+func TestKeepLogsDSNWhenProviderHasNoInspectCommand(t *testing.T) {
+	spy := &verboseSpyTB{TB: t}
+	db, err := New(spy, &mockProvider{}, nil) // mockProvider has no InspectCommand
+	if err != nil {
+		t.Fatal(err)
+	}
+	db.Keep()
+	if err := db.Close(); err != nil {
+		t.Fatal(err)
+	}
+	var kept string
+	for _, msg := range spy.logs {
+		if strings.Contains(msg, "kept database") {
+			kept = msg
+		}
+	}
+	if !strings.Contains(kept, db.DSN()) {
+		t.Errorf("without an InspectCommander the log should show the DSN, got: %s", kept)
 	}
 }
 

migrate/golangmigrate/go.mod

@@ -4,11 +4,13 @@ go 1.27.0
 
 require (
 	github.com/bashhack/testdb v0.0.0
+	github.com/go-sql-driver/mysql v1.10.1
 	github.com/golang-migrate/migrate/v4 v4.20.1
-	github.com/jackc/pgx/v5 v5.9.2
+	github.com/jackc/pgx/v5 v5.11.0
 )
 
 require (
+	filippo.io/edwards25519 v1.2.0 // indirect
 	github.com/jackc/pgerrcode v0.0.0-20220416144525-469b46aa5efa // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect

migrate/golangmigrate/go.sum

@@ -1,3 +1,5 @@
+filippo.io/edwards25519 v1.2.0 h1:crnVqOiS4jqYleHd9vaKZ+HKtHfllngJIiOpNpoJsjo=
+filippo.io/edwards25519 v1.2.0/go.mod h1:xzAOLCNug/yB62zG1bQ8uziwrIqIuxhctzJT18Q77mc=
 github.com/Azure/go-ansiterm v0.0.0-20250102033503-faa5f7b0171c h1:udKWzYgxTojEKWjV8V+WSxDXJ4NFATAsZjh8iIbsQIg=
 github.com/Azure/go-ansiterm v0.0.0-20250102033503-faa5f7b0171c/go.mod h1:xomTg63KZ2rFqZQzSB4Vz2SUXa1BpHTVz9L5PTmPC4E=
 github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
@@ -27,6 +29,8 @@ github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
 github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/go-sql-driver/mysql v1.10.1 h1:arlSnNLq6a5yxGxV7qg9lF4j0C+KwD6NbQyKr9QL6ME=
+github.com/go-sql-driver/mysql v1.10.1/go.mod h1:M+cqaI7+xxXGG9swrdeUIoPG3Y3KCkF0pZej+SK+nWk=
 github.com/golang-migrate/migrate/v4 v4.20.1 h1:2N/ToVTKrKl58ynBpgeVJ4In7VcLCjWTZtm4eP1LxhU=
 github.com/golang-migrate/migrate/v4 v4.20.1/go.mod h1:DDPgKVb4ovSWc4FwSPfV2Uz1160f4XBiTHTrAJtljmM=
 github.com/jackc/pgerrcode v0.0.0-20220416144525-469b46aa5efa h1:s+4MhCQ6YrzisK6hFJUX53drDT4UsSW3DEhKn0ifuHw=
@@ -35,8 +39,8 @@ github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsI
 github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
 github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 h1:iCEnooe7UlwOQYpKFhBabPMi4aNAfoODPEFNiAnClxo=
 github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761/go.mod h1:5TJZWKEWniPve33vlWYSoGYefn3gLQRzjfDlhSJ9ZKM=
-github.com/jackc/pgx/v5 v5.9.2 h1:3ZhOzMWnR4yJ+RW1XImIPsD1aNSz4T4fyP7zlQb56hw=
-github.com/jackc/pgx/v5 v5.9.2/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
+github.com/jackc/pgx/v5 v5.11.0 h1:IzBBtyK9AHqf98cctWFifYSci2hgQR/cd56wB4p+ogg=
+github.com/jackc/pgx/v5 v5.11.0/go.mod h1:mal1tBGAFfLHvZzaYh77YS/eC6IX9OWbRV1QIIM0Jn4=
 github.com/jackc/puddle/v2 v2.2.2 h1:PR8nw+E/1w0GLuRFSmiioY6UooMp6KJv0/61nB7icHo=
 github.com/jackc/puddle/v2 v2.2.2/go.mod h1:vriiEXHvEE654aYKXXjOvZM39qJ0q+azkZFrfEOc3H4=
 github.com/jinzhu/inflection v1.0.0 h1:K317FqzuhWc8YvSVlFMCCUb36O/S9MCKRDI7QkRKD/E=

migrate/golangmigrate/golangmigrate.go

@@ -17,14 +17,17 @@ import (
 	"os"
 	"strings"
 
+	mysqldriver "github.com/go-sql-driver/mysql"
 	"github.com/golang-migrate/migrate/v4"
-	// Registers the pgx5:// database driver that this package connects with.
+	// Registers the mysql:// database driver.
+	_ "github.com/golang-migrate/migrate/v4/database/mysql"
+	// Registers the pgx5:// database driver.
 	_ "github.com/golang-migrate/migrate/v4/database/pgx/v5"
 	"github.com/golang-migrate/migrate/v4/source/iofs"
 )
 
-// Migrator applies golang-migrate migrations to a PostgreSQL database.
-// Create one with Dir or FS.
+// Migrator applies golang-migrate migrations to a PostgreSQL or MySQL
+// database. Create one with Dir or FS.
 type Migrator struct {
 	fsys fs.FS
 	path string
@@ -101,18 +104,28 @@ func (m *Migrator) Migrate(ctx context.Context, dsn string) (err error) {
 	return nil
 }
 
-// databaseURL rewrites the DSN's scheme to pgx5, the one golang-migrate's
-// pgx/v5 driver registers; the rest of the URL is the same.
+// databaseURL turns a testdb DSN into the URL golang-migrate's drivers
+// register for: a PostgreSQL URL gets the pgx5 scheme, and go-sql-driver's
+// native MySQL DSN (which has no scheme) is prefixed with mysql://, which is
+// the form golang-migrate's MySQL driver parses.
 func databaseURL(dsn string) (string, error) {
+	if !strings.Contains(dsn, "://") {
+		if _, err := mysqldriver.ParseDSN(dsn); err == nil {
+			return "mysql://" + dsn, nil
+		}
+		return "", errors.New("golangmigrate: the DSN must be a PostgreSQL URL (postgres://...) or a native MySQL DSN (user:pass@tcp(host:port)/db)")
+	}
 	u, err := url.Parse(dsn)
-	if err != nil || u.Scheme == "" {
-		return "", errors.New("golangmigrate: the DSN must be a URL (postgres://...)")
+	if err != nil {
+		return "", fmt.Errorf("golangmigrate: parse DSN: %w", err)
 	}
 	switch strings.ToLower(u.Scheme) {
 	case "postgres", "postgresql", "pgx", "pgx5":
 		u.Scheme = "pgx5"
+	case "mysql":
+		return "", errors.New("golangmigrate: give MySQL DSNs in go-sql-driver's native form (user:pass@tcp(host:port)/db), as testdb's mysql package does")
 	default:
-		return "", fmt.Errorf("golangmigrate: unsupported DSN scheme %q; only PostgreSQL is supported", u.Scheme)
+		return "", fmt.Errorf("golangmigrate: unsupported DSN scheme %q", u.Scheme)
 	}
 	return u.String(), nil
 }