summercms/modules/lagoon

lagoon

Postgres data layer: the shared GORM connection, per-plugin migrations, model helpers and file attachments.

import "git.golem15.com/golem15/summercms/modules/lagoon"

import "git.golem15.com/golem15/summercms/modules/lagoon/attach"

Overview

lagoon is the WinterCMS models and migrations counterpart: it opens the one *sql.DB pool (pgx stdlib driver) that GORM and the rest of the application share, runs each plugin's gormigrate set in its own history table, and ports the Eloquent model conventions that WinterCMS plugins rely on, such as $fillable, $hidden, $jsonable, encrypted casts and Laravel-style validation rules. Its attach subpackage ports WinterCMS's system_files attachments, storing originals and lazily generated thumbnails in a gocloud.dev blob bucket. The application binary gets the migrate and key commands from lagoon.RuntimeCommands.

Features

• One shared pool: lagoon.Open, lagoon.Use and lagoon.OpenFromApp return a *sql.DB and a *gorm.DB built on that same pool; lagoon.Publish makes both available on the backpack.App.
• Database-ready hooks: lagoon.OnDatabase runs a callback with the pool and GORM handle as soon as the database is published, immediately when it already is, otherwise when lagoon.Publish runs. Plugins register GORM callbacks through it from Boot, which runs before the serve command publishes the database.
• After-commit work: lagoon.Transaction runs a function in a transaction and then the callbacks registered with lagoon.AfterCommit, in order, only after the commit succeeds; a nested lagoon.Transaction is a savepoint whose callbacks are dropped with it when it fails. A nested lagoon.Transaction must be given the outer transaction's handle: given a root handle it returns an error without running its function, rather than open an independent transaction whose callbacks would wait on the outer one. A single-statement write for which GORM opens its own implicit transaction runs its callbacks from lagoon:after_commit once GORM commits, and never when the write fails. A callback registered inside a foreign plain GORM transaction is unsafe because Lagoon cannot observe its commit, so lagoon.AfterCommit warns and skips it. Outside a transaction, callbacks run immediately. The handle a supported callback receives always has an empty statement on the connection its work belongs to. A panicking callback is logged and never turns a committed write into an error.
• Database check at connect time: lagoon.CheckLocale refuses a database whose default collation is not the ICU pl-PL locale, so ordering matches the database default without per-query COLLATE.
• Per-plugin migrations: lagoon.Migrate runs the framework's system_files set (attach.Migrations), backend admin identity set (lagoon.BackendAdminMigrations) and job-queue set (lagoon.QueueMigrations: River's schema pinned at lagoon.RiverSchemaVersion, then the lagoon.JobsTable record table, under the lagoon.QueueHistoryID history), then every pact.HasMigrations set in plugin activation order, each in its own summer_migrations_<plugin_id> history table (lagoon.HistoryTableName). lagoon.RollbackLast and lagoon.Status cover rollback and history.
• Mass assignment: lagoon.Fill copies only allow-listed keys onto a model by GORM column name and silently drops the rest, logging each dropped key once outside production. A json.Number (from a decoder using UseNumber) fills integer, unsigned and float fields. A value that does not fit its column (a fraction, an exponent or an overflow for an integer field, or a value of the wrong type) is a lagoon.FillTypeError naming the key, so a caller can answer it as a validation failure on that field. lagoon.HasFillable and lagoon.HasHidden are the Go forms of $fillable and $hidden.
• Validation: lagoon.Validate accepts Laravel-style rule strings (required, nullable, integer, numeric, between, min, max, in, unique, boolean, email, confirmed, different, mimes) and returns a field-to-messages map, translated through phrasebook when a translator is given. Unknown rule tokens are an error.
• Safe ordering: lagoon.OrderBy appends an ORDER BY only for an allow-listed column and an asc or desc direction.
• Pagination: lagoon.Paginate builds a lagoon.Page with data and meta (current_page, last_page, per_page, total).
• Column types: lagoon.Encrypted stores AES-256-GCM ciphertext under a key derived from app.key, decrypts with previous keys during rotation, and always redacts itself in JSON and string output; lagoon.Jsonable stores JSON as TEXT and keeps SQL NULL distinct from an empty value.
• Lifecycle and relations: hook interfaces matching GORM's native method names (lagoon.HasBeforeCreate, lagoon.HasBeforeSave, lagoon.HasBeforeDelete, lagoon.HasAfterDelete) plus lagoon.HasBeforeValidate; lagoon.WithSoftDeleteCascade runs a cascade inside the parent delete; lagoon.RegisterJoinTable wires pivot models with business columns.
• Imports from Laravel: lagoon.DecryptLaravelPayload decrypts Laravel encrypted payloads with the old application key, for one-off data imports.
• Attachments (attach): the attach.File model for system_files rows, WinterCMS-compatible partitioned storage keys (attach.BlobKey, attach.PartitionDirectory), on-demand thumbnails through attach.File.Thumb, static serving with an optional is_public gate (attach.StaticHandlerPublic), and a two-phase delete that removes blobs only after the database transaction commits (attach.DeleteForOwner, attach.DeleteKeys).

Usage

Open the shared pool once at boot and publish it, so plugins and handlers reuse the same handles:

sqlDB, gdb, err := lagoon.OpenFromApp(ctx, app)
if err != nil {
	return err
}
if err := lagoon.Publish(app, sqlDB, gdb); err != nil {
	return err
}

A model uses the column types and helpers directly:

type Post struct {
	ID       uint                      `gorm:"column:id;primaryKey"`
	Title    string                    `gorm:"column:title"`
	Tags     lagoon.Jsonable[[]string] `gorm:"column:tags"`
	APIToken lagoon.Encrypted          `gorm:"column:api_token"`
}

func (Post) Fillable() []string { return []string{"title"} }

func createPost(ctx context.Context, gdb *gorm.DB, tr *phrasebook.Translator, input map[string]any) (map[string][]string, error) {
	var post Post
	rules := map[string]string{"title": "required|max:255|unique:posts"}
	if errs, err := lagoon.Validate(ctx, gdb, &post, rules, input, tr); err != nil || errs != nil {
		return errs, err
	}
	if err := lagoon.Fill(&post, post.Fillable(), input, false); err != nil {
		return nil, err
	}
	post.APIToken = lagoon.NewEncrypted("change-me")
	return nil, gdb.Create(&post).Error
}

A plugin registers its GORM callbacks from Boot through lagoon.OnDatabase, so they are installed whenever the database is published, and defers side effects until the write commits:

func (p *Plugin) Boot(app *backpack.App) error {
	return lagoon.OnDatabase(app, func(_ *sql.DB, gdb *gorm.DB) error {
		return gdb.Callback().Create().After("gorm:after_create").Register("acme:post_created", func(db *gorm.DB) {
			if db.Error != nil {
				return
			}
			lagoon.AfterCommit(db.Statement.Context, db, func(ctx context.Context, db *gorm.DB) {
				// runs only once the insert is committed
			})
		})
	})
}

func publish(ctx context.Context, gdb *gorm.DB, post *Post) error {
	return lagoon.Transaction(ctx, gdb, func(ctx context.Context, tx *gorm.DB) error {
		return tx.Create(post).Error // acme:post_created work waits for this commit
	})
}

A plugin ships its schema as an ordered gormigrate set; migrate runs it after the framework sets:

func (p *Plugin) Migrations() []*gormigrate.Migration {
	return []*gormigrate.Migration{{
		ID: "202601010001_create_posts",
		Migrate: func(tx *gorm.DB) error {
			return tx.Exec(`CREATE TABLE posts (id SERIAL PRIMARY KEY, title TEXT NOT NULL, tags TEXT, api_token TEXT)`).Error
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Exec(`DROP TABLE IF EXISTS posts`).Error
		},
	}}
}

API reference

Identifier	Description
lagoon.OpenFromApp	Opens the shared pool from database.dsn and publishes the app.key encryption keys.
lagoon.Open	Opens and pings a DSN, checks the locale and returns the pool plus a GORM handle on it.
lagoon.Use	Returns a GORM handle on an existing pool after the same checks.
lagoon.Publish	Stores the pool and GORM handle on the backpack.App, then runs the callbacks queued by lagoon.OnDatabase.
lagoon.OnDatabase	Runs a callback with the pool and GORM handle once the database is published.
lagoon.Transaction	Runs a function in a transaction (a savepoint when nested) and its lagoon.AfterCommit callbacks after the commit.
lagoon.AfterCommit	Registers work to run after the surrounding transaction commits.
lagoon.AfterCommitCallback	Name of the GORM callback, lagoon:after_commit, that runs single-statement after-commit work.
lagoon.DSN	Reads database.dsn from config.
lagoon.CheckLocale	Fails unless the database default locale is ICU pl-PL.
lagoon.Migrate	Runs framework and plugin migrations in order.
lagoon.RollbackLast	Rolls back the last migration of one plugin.
lagoon.Status	Lists applied migration IDs per plugin as lagoon.StatusRow values.
lagoon.HistoryTableName	Returns the gormigrate history table for a plugin ID.
lagoon.BackendAdminMigrations	Creates the backend user, role and admin token blacklist tables and seeds the system roles.
lagoon.QueueMigrations	Migrates River's schema to lagoon.RiverSchemaVersion and creates the summer_jobs job record table.
lagoon.QueueHistoryID	History id of the job-queue set, summercms.conga.
lagoon.JobsTable	Name of the job record table, summer_jobs.
lagoon.RiverSchemaVersion	The pinned River schema version, 7.
lagoon.RuntimeCommands	Returns the migrate, migrate:rollback, migrate:status and key:generate commands.
lagoon.KeyGenerateCommand	Returns the key:generate command on its own.
lagoon.LoadAppKey	Decodes app.key and app.previous_keys.
lagoon.PublishEncryptionKeys	Installs the keys used by lagoon.Encrypted columns.
lagoon.Encrypted	Encrypted text column; lagoon.Encrypted.Reveal is the only plaintext accessor.
lagoon.Jsonable	Generic JSON-as-TEXT column with NULL tracking.
lagoon.Fill	Allow-listed mass assignment by column name.
lagoon.FillTypeError	Returned by lagoon.Fill when a requested value does not fit its column; Key names the column.
lagoon.Validate	Laravel-style rule validation with a unique database check.
lagoon.OrderBy	Allow-listed ORDER BY.
lagoon.Paginate	Builds a lagoon.Page with lagoon.PageMeta.
lagoon.WithSoftDeleteCascade	Runs a cascade inside the parent delete transaction.
lagoon.RegisterJoinTable	Registers a custom pivot model for a many-to-many field.
lagoon.DecryptLaravelPayload	Decrypts a Laravel AES-256-CBC payload for data imports.
attach.File	The system_files row model.
attach.Owner	Implemented by models that own attachments; returns the stored morph type name.
attach.OpenBucket	Opens the uploads bucket from config.
attach.Publish	Stores the bucket on the backpack.App.
attach.StaticHandler	Serves stored files and thumbnails under a URL prefix.
attach.StaticHandlerPublic	attach.StaticHandler plus a 404 for rows that are not public.
attach.DeleteForOwner	Deletes an owner's attachment rows in a transaction and reports their blob keys.
attach.DeleteKeys	Deletes blobs, including thumbnails, after the transaction commits.
attach.Migrations	Creates the system_files table.

Configuration

Keys are read from the compass config; the SUMMER_ environment overlay maps a double underscore to a dot, for example SUMMER_DATABASE__DSN to database.dsn.

Key	Default	Controls
database.dsn	none (required)	Postgres connection string used by lagoon.OpenFromApp and every database command.
app.key	none (required)	Base64 encoding of 32 random bytes; the source of the lagoon.Encrypted column key. Generate one with key:generate.
app.previous_keys	empty	List of earlier base64 keys still accepted when decrypting, for key rotation.
storage.uploads.bucket_url	none (required by attach.OpenBucket)	Uploads bucket URL, file:// or mem://.
storage.uploads.public_path_prefix	/storage/uploads	URL prefix used when building public file and thumbnail URLs.

database:
  dsn: postgres://acme:<secret>@127.0.0.1:5432/acme?sslmode=disable
app:
  key: <base64 key from key:generate>
storage:
  uploads:
    bucket_url: file:///var/lib/acme/uploads

CLI commands

lagoon.RuntimeCommands adds these commands to the application binary. All of them except key:generate open the database through lagoon.OpenFromApp, so they need database.dsn and app.key.

Command	Flags	Description
migrate	none	Runs the framework migrations, then each plugin's migrations in dependency order.
migrate:rollback	--plugin <id>	Rolls back the last migration of the given plugin; without the flag, of the last activated plugin that has migrations.
migrate:status	none	Prints a table of plugin, history table and applied migration IDs.
key:generate	none	Prints a fresh base64 32-byte key for app.key; writes nothing.

Dependencies

• SummerCMS modules: backpack, bonfire, compass, pact, party, phrasebook (validation messages).
• Third-party: gorm.io/gorm, gorm.io/driver/postgres, github.com/jackc/pgx/v5 (stdlib driver), github.com/go-gormigrate/gormigrate/v2, github.com/go-playground/validator/v10, github.com/riverqueue/river (its rivermigrate and riverdriver/riverdatabasesql packages, for the River schema in lagoon.QueueMigrations).
• Third-party, attach only: gocloud.dev/blob (file and memory drivers), github.com/disintegration/imaging (thumbnails).
• Standard library: database/sql, crypto/aes, crypto/cipher, crypto/hkdf, log/slog, image, among others.

Testing

go test ./modules/lagoon/...

The database tests in lagoon and lagoon/attach start a postgres:16-alpine container, initialised with the ICU pl-PL locale, through testcontainers-go, so they need a running Docker daemon. They are skipped by go test -short ./modules/lagoon/..., which runs only the unit tests.