Add testutils package

Add a `testutils` package containing a shared `TestMain` function and
the `with*` functions used by tests in other packages.

The `SharedTestMain` function creates a new postgres container.

Each of the `with*` functions then creates a new database in that
container for the purposes of the test.

pkg/testutils/db.go

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package testutils
+
+import "math/rand"
+
+func randomDBName() string {
+	const length = 15
+	const charset = "abcdefghijklmnopqrstuvwxyz"
+
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = charset[rand.Intn(len(charset))] // #nosec G404
+	}
+
+	return "testdb_" + string(b)
+}

pkg/testutils/util.go

@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package testutils
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"log"
+	"net/url"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/lib/pq"
+	"github.com/testcontainers/testcontainers-go"
+	"github.com/testcontainers/testcontainers-go/modules/postgres"
+	"github.com/testcontainers/testcontainers-go/wait"
+	"github.com/xataio/pgroll/pkg/roll"
+	"github.com/xataio/pgroll/pkg/state"
+)
+
+// The version of postgres against which the tests are run
+// if the POSTGRES_VERSION environment variable is not set.
+const defaultPostgresVersion = "15.3"
+
+// tConnStr holds the connection string to the test container created in TestMain.
+var tConnStr string
+
+// SharedTestMain starts a postgres container to be used by all tests in a package.
+// Each test then connects to the container and creates a new database.
+func SharedTestMain(m *testing.M) {
+	ctx := context.Background()
+
+	waitForLogs := wait.
+		ForLog("database system is ready to accept connections").
+		WithOccurrence(2).
+		WithStartupTimeout(5 * time.Second)
+
+	pgVersion := os.Getenv("POSTGRES_VERSION")
+	if pgVersion == "" {
+		pgVersion = defaultPostgresVersion
+	}
+
+	ctr, err := postgres.RunContainer(ctx,
+		testcontainers.WithImage("postgres:"+pgVersion),
+		testcontainers.WithWaitStrategy(waitForLogs),
+	)
+	if err != nil {
+		os.Exit(1)
+	}
+
+	tConnStr, err = ctr.ConnectionString(ctx, "sslmode=disable")
+	if err != nil {
+		os.Exit(1)
+	}
+
+	exitCode := m.Run()
+
+	if err := ctr.Terminate(ctx); err != nil {
+		log.Printf("Failed to terminate container: %v", err)
+	}
+
+	os.Exit(exitCode)
+}
+
+func WithMigratorAndConnectionToContainer(t *testing.T, fn func(mig *roll.Roll, db *sql.DB)) {
+	t.Helper()
+	ctx := context.Background()
+
+	tDB, err := sql.Open("postgres", tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := tDB.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	dbName := randomDBName()
+
+	_, err = tDB.ExecContext(ctx, fmt.Sprintf("CREATE DATABASE %s", pq.QuoteIdentifier(dbName)))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u, err := url.Parse(tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u.Path = "/" + dbName
+	connStr := u.String()
+
+	st, err := state.New(ctx, connStr, "pgroll")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = st.Init(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	const lockTimeoutMs = 500
+	mig, err := roll.New(ctx, connStr, "public", lockTimeoutMs, st)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := mig.Close(); err != nil {
+			t.Fatalf("Failed to close migrator connection: %v", err)
+		}
+	})
+
+	db, err := sql.Open("postgres", connStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := db.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	fn(mig, db)
+}
+
+func WithStateAndConnectionToContainer(t *testing.T, fn func(*state.State, *sql.DB)) {
+	t.Helper()
+	ctx := context.Background()
+
+	tDB, err := sql.Open("postgres", tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := tDB.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	dbName := randomDBName()
+
+	_, err = tDB.ExecContext(ctx, fmt.Sprintf("CREATE DATABASE %s", pq.QuoteIdentifier(dbName)))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u, err := url.Parse(tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u.Path = "/" + dbName
+	connStr := u.String()
+
+	st, err := state.New(ctx, connStr, "pgroll")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	db, err := sql.Open("postgres", connStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := db.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	fn(st, db)
+}
+
+func WithMigratorInSchemaWithLockTimeoutAndConnectionToContainer(t *testing.T, schema string, lockTimeoutMs int, fn func(mig *roll.Roll, db *sql.DB)) {
+	t.Helper()
+	ctx := context.Background()
+
+	tDB, err := sql.Open("postgres", tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := tDB.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	dbName := randomDBName()
+
+	_, err = tDB.ExecContext(ctx, fmt.Sprintf("CREATE DATABASE %s", pq.QuoteIdentifier(dbName)))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u, err := url.Parse(tConnStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	u.Path = "/" + dbName
+	connStr := u.String()
+
+	st, err := state.New(ctx, connStr, "pgroll")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = st.Init(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	mig, err := roll.New(ctx, connStr, schema, lockTimeoutMs, st)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := mig.Close(); err != nil {
+			t.Fatalf("Failed to close migrator connection: %v", err)
+		}
+	})
+
+	db, err := sql.Open("postgres", connStr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = db.ExecContext(ctx, fmt.Sprintf("CREATE SCHEMA IF NOT EXISTS %s", schema))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		if err := db.Close(); err != nil {
+			t.Fatalf("Failed to close database connection: %v", err)
+		}
+	})
+
+	fn(mig, db)
+}
+
+func WithMigratorInSchemaAndConnectionToContainer(t *testing.T, schema string, fn func(mig *roll.Roll, db *sql.DB)) {
+	WithMigratorInSchemaWithLockTimeoutAndConnectionToContainer(t, schema, 500, fn)
+}