AsyncPipe; table schemata; migrations; File logging

src/orm/services/Migrations.ts

@@ -0,0 +1,98 @@
+import {Inject, Singleton} from '../../di'
+import {CanonicalInstantiable} from '../../service/CanonicalInstantiable'
+import {Migration} from '../migrations/Migration'
+import {CanonicalDefinition, CanonicalResolver} from '../../service/Canonical'
+import {Migrator} from '../migrations/Migrator'
+import {UniversalPath} from '../../util'
+import {lib} from '../../lib'
+import {CommandLine} from '../../cli'
+import {MigrateDirective} from '../directive/MigrateDirective'
+import {RollbackDirective} from '../directive/RollbackDirective'
+import {CreateMigrationDirective} from '../directive/CreateMigrationDirective'
+
+/**
+ * Service unit that loads and instantiates migration classes.
+ */
+@Singleton()
+export class Migrations extends CanonicalInstantiable<Migration> {
+    @Inject()
+    protected readonly migrator!: Migrator
+
+    @Inject()
+    protected readonly cli!: CommandLine
+
+    protected appPath = ['migrations']
+
+    protected canonicalItem = 'migration'
+
+    protected suffix = '.migration.js'
+
+    async up(): Promise<void> {
+        if ( await this.path.exists() ) {
+            await super.up()
+        } else {
+            this.logging.debug(`Base migration path does not exist, or has no files: ${this.path}`)
+        }
+
+        // Register the migrations for @extollo/lib
+        const basePath = lib().concat('migrations')
+        const resolver = await this.buildMigrationNamespaceResolver('@extollo', basePath)
+        this.registerNamespace('@extollo', resolver)
+
+        // Register the migrate CLI directives
+        this.cli.registerDirective(MigrateDirective)
+        this.cli.registerDirective(RollbackDirective)
+        this.cli.registerDirective(CreateMigrationDirective)
+    }
+
+    async initCanonicalItem(definition: CanonicalDefinition): Promise<Migration> {
+        const instance = await super.initCanonicalItem(definition)
+
+        if ( !(instance instanceof Migration) ) {
+            throw new TypeError(`Invalid migration: ${definition.originalName}. Migrations must extend from @extollo/lib.Migration.`)
+        }
+
+        instance.setMigrationIdentifier(definition.canonicalName)
+
+        return instance
+    }
+
+    /**
+     * Creates a CanonicalResolver for a directory that contains migration files.
+     *
+     * @example
+     * ```ts
+     * const path = universalPath('path', 'to', 'migrations', 'folder')
+     * const namespace = '@mypackage'
+     *
+     * const resolver = await migrations.buildMigrationNamespaceResolver(namespace, path)
+     * migrations.registerNamespace(namespace, resolver)
+     * ```
+     * @param name
+     * @param basePath
+     */
+    public async buildMigrationNamespaceResolver(name: string, basePath: UniversalPath): Promise<CanonicalResolver<Migration>> {
+        if ( !name.startsWith('@') ) {
+            name = `@${name}`
+        }
+
+        const namespace: {[key: string]: Migration} = {}
+
+        for await ( const entry of basePath.walk() ) {
+            if ( !entry.endsWith(this.suffix) ) {
+                this.logging.debug(`buildMigrationNamespaceResolver - Skipping file with invalid suffix: ${entry}`)
+                continue
+            }
+
+            const definition = await this.buildCanonicalDefinition(entry, basePath)
+            this.logging.verbose(`buildMigrationNamespaceResolver - Discovered canonical ${this.canonicalItem} "${definition.canonicalName}" from ${entry}`)
+            namespace[definition.canonicalName] = await this.initCanonicalItem(definition)
+            namespace[definition.canonicalName].setMigrationIdentifier(`${name}:${namespace[definition.canonicalName].identifier}`)
+        }
+
+        return {
+            get: (key: string) => namespace[key],
+            all: () => Object.keys(namespace),
+        }
+    }
+}