feat(plugin-tools): first version of the package with some nice plugin utilities

packages/plugin-tools/src/index.ts

@@ -0,0 +1,56 @@
+import { type GeneratorPlugin, type StoragePlugin } from './types.js';
+
+export const createStoragePlugin = (initialize: StoragePlugin['initialize']): StoragePlugin => {
+  return {
+    type: 'storage',
+    initialize,
+  };
+};
+
+export const createGeneratorPlugin = (generate: GeneratorPlugin['generate']): GeneratorPlugin => {
+  return {
+    type: 'generator',
+    generate,
+  };
+};
+
+export const isGeneratorPlugin = (plugin: any): plugin is GeneratorPlugin => {
+  if (!plugin || typeof plugin !== 'object') {
+    return false;
+  }
+
+  if (plugin.type === 'generator') {
+    return typeof plugin.generate === 'function';
+  }
+
+  return false;
+};
+
+export const isStoragePlugin = (plugin: any): plugin is StoragePlugin => {
+  if (!plugin || typeof plugin !== 'object') {
+    return false;
+  }
+
+  if (plugin.type === 'storage') {
+    return typeof plugin.initialize === 'function';
+  }
+
+  return false;
+};
+
+/**
+ * Get a timestamp string in the format YYYYMMDDHHmmssmmm based on the current time (UTC)
+ *
+ * Can be used to prefix migration filenames so that they are executed in the correct order
+ *
+ * @returns A timestamp string in the format YYYYMMDDHHmmssmmm
+ */
+export const getTimestampPrefix = () => new Date().toISOString().replaceAll(/[-:ZT.]/g, '');
+
+/**
+ * A utility function to sanitize a migration name so that it can be used as a filename
+ *
+ * @param name A migration name to sanitize
+ * @returns A sanitized migration name that can be used as a filename
+ */
+export const sanitizeMigrationName = (name: string) => name.replaceAll(/[\W/\\:|*?'"<>]/g, '_').trim();

packages/plugin-tools/src/types.ts

@@ -0,0 +1,88 @@
+export type MigrationStatus = 'failed' | 'done';
+
+export type MigrationHistoryEntry = {
+  name: string;
+  status: MigrationStatus;
+  date: Date;
+  error?: unknown;
+};
+
+export type Storage = {
+  /**
+   * Acquire a lock on the given migrations.
+   *
+   * To best support concurrent migrations (e.g. when multiple services are deployed at the same time and want to migrate the same database)
+   * the plugin should try to lock all migrations at once (i.e. in a transaction) and ignore migrations that are already locked (or done).
+   * The successfully locked migrations should be returned and are the migrations that will be executed.
+   *
+   * If one of the migrations to lock is in a failed state, the plugin should throw an error to abort the migration attempt.
+   *
+   * @returns The migrations that were successfully locked.
+   */
+  lock(migrations: string[]): Promise<string[]>;
+  /**
+   * The unlock method is called after all migrations have been executed or when the process is interrupted (e.g. by a SIGTERM or SIGINT signal).
+   *
+   * Depending on the plugin implementation, the unlock method is usually a no-op for already succeeded or failed migrations.
+   *
+   * @param migrations The previously successfully locked migrations that should now be unlocked.
+   */
+  unlock(migrations: string[]): Promise<void>;
+  /**
+   * Get the history of previously executed migrations.
+   *
+   * For failed migrations, the error property should be set.
+   * Emigrate will not sort the history entries, so the plugin should return the entries in the order they were executed.
+   * The order doesn't affect the execution of migrations, but it does affect the order in which the history is displayed in the CLI.
+   * Migrations that have not yet been executed will always be run in alphabetical order.
+   *
+   * The history has two purposes:
+   * 1. To determine which migrations have already been executed.
+   * 2. To list the migration history in the CLI.
+   */
+  getHistory(): AsyncIterable<MigrationHistoryEntry>;
+  /**
+   * Called when a migration has been successfully executed.
+   *
+   * @param migration The name of the migration that should be marked as done.
+   */
+  onSuccess(migration: string): Promise<void>;
+  /**
+   * Called when a migration has failed.
+   *
+   * @param migration The name of the migration that should be marked as failed.
+   * @param error The error that caused the migration to fail.
+   */
+  onError(migration: string, error: Error): Promise<void>;
+};
+
+export type StoragePlugin = {
+  type: 'storage';
+  initialize(): Promise<Storage>;
+};
+
+export type MigrationFile = {
+  /**
+   * The complete filename of the migration file, including the extension.
+   *
+   * Migrations that have not yet been executed will be run in alphabetical order, so preferably prefix the filename with a timestamp (and avoid unix timestamp and prefer something more human readable).
+   */
+  filename: string;
+  /**
+   * The content of the migration file.
+   */
+  content: string;
+};
+
+export type GeneratorPlugin = {
+  type: 'generator';
+  /**
+   * Used to generate a new migration file.
+   *
+   * @param name The name of the migration that should be generated (provided as arguments to the CLI)
+   * @returns The generated migration file.
+   */
+  generate(name: string): Promise<MigrationFile>;
+};
+
+export type Plugin = StoragePlugin | GeneratorPlugin;