snapshot of https://github.com/ent/ent.git (master, 2026-09-15; blobs > 131072B omitted)

examples/migration/ent/migrate/migratedata/migratedata.go

@@ -0,0 +1,120 @@
+// Copyright 2019-present Facebook Inc. All rights reserved.
+// This source code is licensed under the Apache 2.0 license found
+// in the LICENSE file in the root directory of this source tree.
+
+//go:build migratedata_20221126185750
+
+// Package migratedata holds the functions for generating data migration files.
+// It exists here for documentation and reference purpose only and has no runtime
+// effect on the actual migration files.
+package migratedata
+
+import (
+	"context"
+	"fmt"
+
+	"ariga.io/atlas/sql/migrate"
+	"entgo.io/ent/dialect"
+	"entgo.io/ent/dialect/sql"
+	"entgo.io/ent/dialect/sql/schema"
+	"entgo.io/ent/dialect/sql/sqljson"
+	"entgo.io/ent/examples/migration/ent"
+	"entgo.io/ent/examples/migration/ent/user"
+)
+
+// BackfillUserTags was used to generate the migration file '20221126185750_backfill_user_tags.sql'.
+// It exists here for documentation purpose only, and can be used as a reference for future data migrations.
+func BackfillUserTags(dir *migrate.LocalDir) error {
+	w := &schema.DirWriter{Dir: dir}
+	client := ent.NewClient(ent.Driver(schema.NewWriteDriver(dialect.MySQL, w)))
+
+	// Add defaults "foo" and "bar" tags for users without any.
+	err := client.User.
+		Update().
+		Where(func(s *sql.Selector) {
+			s.Where(
+				sql.Or(
+					sql.IsNull(user.FieldTags),
+					sqljson.ValueIsNull(user.FieldTags),
+				),
+			)
+		}).
+		SetTags([]string{"foo", "bar"}).
+		Exec(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed generating backfill statement: %w", err)
+	}
+	// Document all changes until now with a custom comment.
+	w.Change("Backfill NULL or null tags with a default value.")
+
+	// Append the "org" special tag for users with a specific prefix or suffix.
+	err = client.User.
+		Update().
+		Where(
+			user.Or(
+				user.NameHasPrefix("org-"),
+				user.NameHasSuffix("-org"),
+			),
+			// Append to only those without this tag.
+			func(s *sql.Selector) {
+				s.Where(
+					sql.Not(sqljson.ValueContains(user.FieldTags, "org")),
+				)
+			},
+		).
+		AppendTags([]string{"org"}).
+		Exec(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed generating backfill statement: %w", err)
+	}
+	// Document all changes until now with a custom comment.
+	w.Change("Append the 'org' tag for organization accounts in case they don't have it.")
+
+	// Write the content to the migration directory.
+	return w.Flush("backfill_user_tags")
+}
+
+// BackfillUnknown back-fills all empty users' names with the default value 'Unknown'.
+func BackfillUnknown(dir *migrate.LocalDir) error {
+	w := &schema.DirWriter{Dir: dir}
+	client := ent.NewClient(ent.Driver(schema.NewWriteDriver(dialect.MySQL, w)))
+
+	// Change all empty names to 'unknown'.
+	err := client.User.
+		Update().
+		Where(
+			user.NameEQ(""),
+		).
+		SetName("Unknown").
+		Exec(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed generating statement: %w", err)
+	}
+
+	// Write the content to the migration directory.
+	return w.FlushChange(
+		"unknown_names",
+		"Backfill all empty user names with default value 'unknown'.",
+	)
+}
+
+// SeedUsers add the initial users to the database.
+func SeedUsers(dir *migrate.LocalDir) error {
+	w := &schema.DirWriter{Dir: dir}
+	client := ent.NewClient(ent.Driver(schema.NewWriteDriver(dialect.MySQL, w)))
+
+	// The statement that generates the INSERT statement.
+	err := client.User.CreateBulk(
+		client.User.Create().SetName("a8m").SetAge(1).SetTags([]string{"foo"}),
+		client.User.Create().SetName("nati").SetAge(1).SetTags([]string{"bar"}),
+	).Exec(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed generating statement: %w", err)
+	}
+
+	// Write the content to the migration directory.
+	return w.FlushChange(
+		"seed_users",
+		"Add the initial users to the database.",
+	)
+}