pocketbase/migrations/1679943780_normalize_single_multiple_values.go

package migrations

import (
	"fmt"

	"github.com/pocketbase/dbx"
	"github.com/pocketbase/pocketbase/daos"
	"github.com/pocketbase/pocketbase/models"
	"github.com/pocketbase/pocketbase/models/schema"
)

// Normalizes old single and multiple values of MultiValuer fields (file, select, relation).
func init() {
	AppMigrations.Register(func(db dbx.Builder) error {
		dao := daos.New(db)

		collections := []*models.Collection{}
		if err := dao.CollectionQuery().All(&collections); err != nil {
			return err
		}

		for _, c := range collections {
			if c.IsView() {
				// skip view collections
				continue
			}

			for _, f := range c.Schema.Fields() {
				opt, ok := f.Options.(schema.MultiValuer)
				if !ok {
					continue
				}

				var updateQuery *dbx.Query

				if opt.IsMultiple() {
					updateQuery = dao.DB().NewQuery(fmt.Sprintf(
						`UPDATE {{%s}} set [[%s]] = (
							CASE
								WHEN COALESCE([[%s]], '') = ''
								THEN '[]'
								ELSE (
									CASE
										WHEN json_valid([[%s]]) AND json_type([[%s]]) == 'array'
										THEN [[%s]]
										ELSE json_array([[%s]])
									END
								)
							END
						)`,
						c.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
					))
				} else {
					updateQuery = dao.DB().NewQuery(fmt.Sprintf(
						`UPDATE {{%s}} set [[%s]] = (
							CASE
								WHEN COALESCE([[%s]], '[]') = '[]'
								THEN ''
								ELSE (
									CASE
										WHEN json_valid([[%s]]) AND json_type([[%s]]) == 'array'
										THEN COALESCE(json_extract([[%s]], '$[#-1]'), '')
										ELSE [[%s]]
									END
								)
							END
						)`,
						c.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
						f.Name,
					))
				}

				if _, err := updateQuery.Execute(); err != nil {
					return err
				}
			}
		}

		// trigger view query update after the records normalization
		// (ignore save error in case of invalid query to allow users to change it from the UI)
		for _, c := range collections {
			if !c.IsView() {
				continue
			}

			dao.SaveCollection(c)
		}

		return nil
	}, func(db dbx.Builder) error {
		return nil
	})
}