Pocketbase Migrations

PocketBase Migrations

Guide for creating PocketBase migrations using the Go-based system (0.20+).

Core Workflow

Critical Migration Pattern

ALWAYS follow this workflow:

1. Write ONE migration at a time
2. Execute immediately with mise run migrate
3. Verify it worked with mise run show-collections
4. Only then write the next migration
5. Run mise run backup before destructive changes

Never write multiple migrations without running them between each one.

Migration Structure

package migrations

import (
    "github.com/pocketbase/pocketbase/core"
    "github.com/pocketbase/pocketbase/tools/types"
    m "github.com/pocketbase/pocketbase/migrations"
)

func init() {
    m.Register(func(app core.App) error {
        // Up migration
        return nil
    }, func(app core.App) error {
        // Down migration
        return nil
    })
}

Collection Operations

Create Base Collection

collection := core.NewBaseCollection("posts")

// Add fields
collection.Fields.Add(&core.TextField{
    Name: "title",
    Required: true,
    Max: 100,
})

// Set rules (use types.Pointer())
collection.ListRule = types.Pointer("@request.auth.id != ''")
collection.CreateRule = types.Pointer("@request.auth.id != ''")
collection.UpdateRule = types.Pointer("@request.auth.id = author")
collection.DeleteRule = types.Pointer("@request.auth.id = author")

return app.Save(collection)

Update Existing Collection

collection, err := app.FindCollectionByNameOrId("posts")
if err != nil {
    return err
}

// Add field
collection.Fields.Add(&core.DateField{
    Name: "publishedAt",
})

// Remove field
collection.Fields.RemoveByName("oldField")

// Update rules
collection.UpdateRule = types.Pointer("@request.auth.id = author")

return app.Save(collection)

Common Field Types

See references/field-types.md for complete field type reference.

Quick Reference

// Text
&core.TextField{Name: "title", Required: true, Max: 100}

// Number
&core.NumberField{Name: "price", Min: types.Pointer(0.0)}

// Boolean
&core.BoolField{Name: "isActive"}

// Email
&core.EmailField{Name: "email", Required: true}

// Date
&core.DateField{Name: "publishedAt"}

// Auto-managed date
&core.AutodateField{Name: "created", OnCreate: true}

// Select
&core.SelectField{
    Name: "status",
    Values: []string{"draft", "published"},
    MaxSelect: 1,
}

// File
&core.FileField{
    Name: "avatar",
    MaxSelect: 1,
    MaxSize: 5242880, // bytes
}

// Editor (rich text)
&core.EditorField{
    Name: "content",
    MaxSize: 1048576,
}

// JSON
&core.JSONField{Name: "metadata", MaxSize: 65535}

Working with Relations

Best Practices

1. Create collections in dependency order
2. Fetch collections before creating relations
3. Use actual collection IDs for relations
4. Handle self-referencing relations in separate migrations

Relation Field

// Fetch the target collection first
authorsCollection, err := app.FindCollectionByNameOrId("authors")
if err != nil {
    return err
}

// Add relation field
collection.Fields.Add(&core.RelationField{
    Name: "author",
    Required: true,
    MaxSelect: 1,  // Note: use MaxSelect, not Max
    CollectionId: authorsCollection.Id,
    CascadeDelete: true,
})

// System users collection
collection.Fields.Add(&core.RelationField{
    Name: "creator",
    CollectionId: "_pb_users_auth_",
    MaxSelect: 1,
})

Migration Order for Relations

Create collections in this order:

1. Independent collections (no relations)
2. Collections depending on system collections
3. Collections with relations to other custom collections
4. Self-referencing relations (separate migration)

Example order:

1_create_categories.go       # Independent
2_create_authors.go          # Depends on system users
3_create_posts.go           # Depends on authors & categories
4_create_comments.go        # Depends on posts & users
5_add_parent_to_comments.go # Self-referencing

Collection Rules

Rule Types

• ListRule - List records
• ViewRule - View individual records
• CreateRule - Create records
• UpdateRule - Update records
• DeleteRule - Delete records

Common Patterns

// Public access
types.Pointer("")

// Authenticated only
types.Pointer("@request.auth.id != ''")

// Owner only
types.Pointer("@request.auth.id = author")

// Published or owner
types.Pointer("status = 'published' || author = @request.auth.id")

// Through relations
types.Pointer("author.user = @request.auth.id")

View Collections

viewQuery := `
SELECT 
    posts.id,
    posts.title,
    users.name as author_name
FROM posts
JOIN users ON posts.author = users.id
`
collection := core.NewViewCollection("posts_with_authors", viewQuery)
return app.Save(collection)

Error Handling

Always check errors:

collection, err := app.FindCollectionByNameOrId("posts")
if err != nil {
    return err
}

if err := app.Save(collection); err != nil {
    return err
}

Task Commands

• mise run makemigration <name> - Create new migration file
• mise run migrate - Run pending migrations
• mise run migratedown - Rollback last migration
• mise run show-collections - Display collections
• mise run backup - Backup database to /tmp

Best Practices

1. Import types package for nullable values: "github.com/pocketbase/pocketbase/tools/types"
2. Use types.Pointer() for rule assignments and pointer values
3. Check collection existence before creating relations
4. Validate field names don't conflict with system fields (id, created, updated)
5. Handle errors immediately after operations
6. Never skip migration testing - run each one before writing the next
7. Backup before destructive changes

Common Gotchas

• Use MaxSelect (not Max) for RelationField
• Use MaxSize (not Max) for EditorField
• System users collection ID: "_pb_users_auth_"
• For number min/max: types.Pointer(0.0)
• Empty rules need: types.Pointer("")
• Self-referencing relations need separate migrations

Additional Resources

• Field types reference: references/field-types.md
• Official docs: https://pocketbase.io/docs/go-collections/