daddy/cmd/server/migration.go

package main

import (
	"context"

	"forge.cadoles.com/Cadoles/daddy/internal/database"
	"forge.cadoles.com/Cadoles/daddy/internal/migration"
	"github.com/jackc/pgx/v4"
	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
	"gitlab.com/wpetit/goweb/service"
)

const (
	migrateUp     = "up"
	migrateLatest = "latest"
	migrateDown   = "down"
)

func applyMigration(ctx context.Context, ctn *service.Container) error {
	migr, err := migration.From(ctn)
	if err != nil {
		return err
	}

	// Register available migrations
	migr.Register(
		m000initialSchema(),
	)

	currentVersion, err := migr.CurrentVersion(ctx)
	if err != nil {
		return errors.Wrap(err, "could not retrieve current data schema version")
	}

	switch migrate {
	case migrateUp:
		if err := migr.Up(ctx); err != nil {
			return errors.Wrap(err, "could not apply up migration")
		}

	case migrateLatest:
		latestVersion, err := migr.LatestVersion()
		if err != nil {
			return errors.Wrap(err, "could not retrieve latest data schema version")
		}

		logger.Info(
			ctx,
			"migrating data schema to latest version",
			logger.F("currentVersion", currentVersion),
			logger.F("latestVersion", latestVersion),
		)

		// Execute migration to latest available version
		if err := migr.Latest(ctx); err != nil {
			return errors.Wrap(err, "could not migrate to latest data schema")
		}

	case migrateDown:
		if err := migr.Down(ctx); err != nil {
			return errors.Wrap(err, "could not apply down migration")
		}

	default:
		return errors.Errorf("unknown migration command: '%s'", migrate)
	}

	logger.Info(
		ctx,
		"migration completed",
	)

	return nil
}

func m000initialSchema() migration.Migration {
	return database.NewMigration(
		"00_initial_schema",
		func(ctx context.Context, tx pgx.Tx) error {
			_, err := tx.Exec(ctx, `
			CREATE TABLE users (
				id SERIAL PRIMARY KEY,
				name TEXT,
				email TEXT NOT NULL,
				CONSTRAINT unique_email unique(email)
			);
			`)

			return err
		},
		func(ctx context.Context, tx pgx.Tx) error {
			_, err := tx.Exec(ctx, `
			DROP TABLE users;
			`)

			return err
		},
	)
}