migrate: Add example

migrate/example/example_test.go

@@ -0,0 +1,60 @@
+// Copyright (C) 2017 ScyllaDB
+// Use of this source code is governed by a ALv2-style
+// license that can be found in the LICENSE file.
+
+// +build all integration
+
+package example
+
+import (
+	"context"
+	"testing"
+
+	"github.com/scylladb/gocqlx/v2"
+	"github.com/scylladb/gocqlx/v2/gocqlxtest"
+	"github.com/scylladb/gocqlx/v2/migrate"
+)
+
+// Running examples locally:
+// make run-scylla
+// make run-examples
+func TestExample(t *testing.T) {
+	const ks = "migrate_example"
+
+	cluster := gocqlxtest.CreateCluster()
+	cluster.Keyspace = ks
+
+	if err := gocqlxtest.CreateKeyspace(cluster, ks); err != nil {
+		t.Fatal("CreateKeyspace:", err)
+	}
+	session, err := gocqlx.WrapSession(cluster.CreateSession())
+	if err != nil {
+		t.Fatal("CreateSession:", err)
+	}
+	defer session.Close()
+
+	// Add callback prints
+	printEvent := func(ctx context.Context, session gocqlx.Session, ev migrate.CallbackEvent, name string) error {
+		t.Log(ev, name)
+		return nil
+	}
+
+	reg := migrate.CallbackRegister{}
+	reg.Add(migrate.BeforeMigration, "m1.cql", printEvent)
+	reg.Add(migrate.AfterMigration, "m1.cql", printEvent)
+	reg.Add(migrate.CallComment, "1", printEvent)
+	reg.Add(migrate.CallComment, "2", printEvent)
+	reg.Add(migrate.CallComment, "3", printEvent)
+
+	migrate.Callback = reg.Callback
+
+	// First run prints data
+	if err := migrate.Migrate(context.Background(), session, "migrations"); err != nil {
+		t.Fatal("Migrate:", err)
+	}
+
+	// Second run skips the processed files
+	if err := migrate.Migrate(context.Background(), session, "migrations"); err != nil {
+		t.Fatal("Migrate:", err)
+	}
+}