feat: initial Migrator implementation

package.json

@@ -45,7 +45,8 @@
   "dependencies": {
     "@antwika/common": "0.0.17",
     "mongodb": "^4.6.0",
-    "mongodb-memory-server": "^8.6.0"
+    "mongodb-memory-server": "^8.6.0",
+    "zod": "^3.17.3"
   },
   "files": [
     "bin",

src/IStore.ts

@@ -22,4 +22,5 @@ export interface IStore {
   readAll: <T>() => Promise<WithId<T>[]>;
   update: <T>(data: WithId<T>) => Promise<void>;
   delete: (id: DataId) => Promise<void>;
+  replace: <T>(data: WithId<T>) => Promise<void>;
 }

src/MemoryStore.ts

@@ -50,11 +50,15 @@ export class MemoryStore implements IStore {
   }
 
   async update<T>(data: WithId<T>) {
-    this.database[data.id] = data;
+    this.database[data.id] = { ...this.database[data.id], ...data };
   }
 
   async delete(id: DataId) {
     if (!this.database[id]) throw new Error('Could not delete non-existant data');
     delete this.database[id];
   }
+
+  async replace<T>(data: WithId<T>) {
+    this.database[data.id] = data;
+  }
 }

src/Migrator.ts

@@ -0,0 +1,62 @@
+import { IStore } from './IStore';
+import { Migration } from './schema/Migration';
+
+type MigrationStatus = {
+  atTimestamp: Date,
+};
+
+export class Migrator {
+  private migrationStatus: MigrationStatus;
+
+  constructor() {
+    this.migrationStatus = {
+      atTimestamp: new Date('1970-01-01'),
+    };
+  }
+
+  async upgrade(store: IStore, migrations: Migration[]) {
+    const sorted = migrations.sort((a, b) => (
+      new Date(a.timestamp) > new Date(b.timestamp) ? 1 : -1
+    ));
+
+    console.log('sorted migrations:', sorted);
+
+    for (const migration of migrations) {
+      if (new Date(migration.timestamp) <= this.migrationStatus.atTimestamp) {
+        console.log(`Already migrated: ${migration.name}`);
+        // eslint-disable-next-line no-continue
+        continue;
+      }
+
+      console.log(`Running migration: ${migration.name}`);
+      // eslint-disable-next-line no-await-in-loop
+      await migration.up(store);
+
+      console.log('setting atTimestamp:', new Date(migration.timestamp));
+      this.migrationStatus.atTimestamp = new Date(migration.timestamp);
+    }
+  }
+
+  async downgrade(store: IStore, migrations: Migration[]) {
+    const sorted = migrations.sort((a, b) => (
+      new Date(a.timestamp) <= new Date(b.timestamp) ? 1 : -1
+    ));
+
+    console.log('reverse sorted migrations:', sorted);
+
+    for (const migration of migrations) {
+      if (new Date(migration.timestamp) > this.migrationStatus.atTimestamp) {
+        console.log(`Already migrated: ${migration.name}`);
+        // eslint-disable-next-line no-continue
+        continue;
+      }
+
+      console.log(`Running migration (downgrade): ${migration.name}`);
+      // eslint-disable-next-line no-await-in-loop
+      await migration.down(store);
+
+      console.log('setting atTimestamp:', new Date(migration.timestamp));
+      this.migrationStatus.atTimestamp = new Date(migration.timestamp);
+    }
+  }
+}

src/MongoDbStore.ts

@@ -182,6 +182,17 @@ export class MongoDbStore implements IStore {
     }
   }
 
+  async replace<T>(data: WithId<T>) {
+    const connection = await this.getConnection();
+    const database = connection.db(this.database);
+    const collection = database.collection(this.collection);
+    await collection.replaceOne(
+      { _id: new ObjectId(this.ensureHex(data.id, 24)) },
+      { ...data, _id: new ObjectId(this.ensureHex(data.id, 24)) },
+      { upsert: false },
+    );
+  }
+
   /**
    * @deprecated
    */

src/schema/Migration.ts

@@ -0,0 +1,8 @@
+import { IStore } from '../IStore';
+
+export type Migration = {
+  name: string,
+  timestamp: string,
+  up: (store: IStore) => Promise<void>;
+  down: (store: IStore) => Promise<void>;
+};

src/schema/User.ts

@@ -0,0 +1,25 @@
+import { z } from 'zod';
+
+export const UserV1Schema = z.object({
+  firstname: z.string(),
+  lastname: z.string(),
+});
+
+export type UserV1 = z.infer<typeof UserV1Schema>;
+
+export const UserV2Schema = z.object({
+  firstname: z.string(),
+  lastname: z.string(),
+  fullname: z.string(),
+});
+
+export type UserV2 = z.infer<typeof UserV2Schema>;
+
+export const UserV3Schema = z.object({
+  firstname: z.string(),
+  lastname: z.string(),
+  fullname: z.string(),
+  shortname: z.string(),
+});
+
+export type UserV3 = z.infer<typeof UserV3Schema>;

test/migration.test.ts

@@ -0,0 +1,59 @@
+/* eslint-disable no-lone-blocks */
+import { IStore, WithId } from '../src/IStore';
+import { MemoryStore } from '../src/MemoryStore';
+import { migrationV2 } from './migrations/migrationV2';
+import { migrationV3 } from './migrations/migrationV3';
+import { Migrator } from '../src/Migrator';
+import { UserV1, UserV3 } from '../src/schema/User';
+
+describe('migration', () => {
+  let store: IStore;
+
+  beforeAll(async () => {
+    store = new MemoryStore();
+    await store.connect();
+  });
+
+  afterAll(async () => {
+    await store.disconnect();
+  });
+
+  // eslint-disable-next-line jest/expect-expect
+  it('migrates.', async () => {
+    const userV1: UserV1 = { firstname: 'Anna', lastname: 'Andersson' };
+
+    const user = await store.createWithoutId(userV1);
+
+    const migrator = new Migrator();
+
+    await migrator.upgrade(store, [
+      migrationV2,
+      migrationV3,
+    ]);
+
+    {
+      const found: WithId<UserV3> = await store.read(user.id);
+      expect(found).toStrictEqual({
+        id: expect.any(String),
+        firstname: 'Anna',
+        lastname: 'Andersson',
+        fullname: 'Anna Andersson',
+        shortname: 'AnnAnd',
+      });
+    }
+
+    await migrator.downgrade(store, [
+      migrationV2,
+      migrationV3,
+    ]);
+
+    {
+      const found: WithId<UserV1> = await store.read(user.id);
+      expect(found).toStrictEqual({
+        id: expect.any(String),
+        firstname: 'Anna',
+        lastname: 'Andersson',
+      });
+    }
+  });
+});

test/migrations/migrationV2.ts

@@ -0,0 +1,30 @@
+import { IStore } from '../../src/IStore';
+import { Migration } from '../../src/schema/Migration';
+import { UserV1, UserV2 } from '../../src/schema/User';
+
+export const migrationV2: Migration = {
+  name: 'add "fullname".',
+  timestamp: new Date('2000-01-01').toISOString(),
+  up: async (store: IStore) => {
+    const users = await store.readAll<UserV1>();
+    for (const user of users) {
+      const userV2 = {
+        ...user,
+        fullname: `${user.firstname} ${user.lastname}`,
+      };
+      // eslint-disable-next-line no-await-in-loop
+      await store.update<UserV2>(userV2);
+    }
+  },
+  down: async (store: IStore) => {
+    const users = await store.readAll<UserV2>();
+    for (const user of users) {
+      // eslint-disable-next-line no-await-in-loop
+      await store.replace<UserV1>({
+        id: user.id,
+        firstname: user.firstname,
+        lastname: user.lastname,
+      });
+    }
+  },
+};

test/migrations/migrationV3.ts

@@ -0,0 +1,31 @@
+import { IStore } from '../../src/IStore';
+import { Migration } from '../../src/schema/Migration';
+import { UserV2, UserV3 } from '../../src/schema/User';
+
+export const migrationV3: Migration = {
+  name: 'add "shortname".',
+  timestamp: new Date('2000-01-02').toISOString(),
+  up: async (store: IStore) => {
+    const users = await store.readAll<UserV2>();
+    for (const user of users) {
+      const userV3 = {
+        ...user,
+        shortname: `${user.firstname.substring(0, 3)}${user.lastname.substring(0, 3)}`,
+      };
+      // eslint-disable-next-line no-await-in-loop
+      await store.update<UserV3>(userV3);
+    }
+  },
+  down: async (store: IStore) => {
+    const users = await store.readAll<UserV3>();
+    for (const user of users) {
+      // eslint-disable-next-line no-await-in-loop
+      await store.replace<UserV2>({
+        id: user.id,
+        firstname: user.firstname,
+        lastname: user.lastname,
+        fullname: user.fullname,
+      });
+    }
+  },
+};

yarn.lock

@@ -5413,3 +5413,8 @@ yocto-queue@^0.1.0:
   version "0.1.0"
   resolved "https://registry.yarnpkg.com/yocto-queue/-/yocto-queue-0.1.0.tgz#0294eb3dee05028d31ee1a5fa2c556a6aaf10a1b"
   integrity sha512-rVksvsnNCdJ/ohGc6xgPwyN8eheCxsiLM8mxuE/t/mOVqJewPuO1miLpTHQiRgTKCLexL4MeAFVagts7HmNZ2Q==
+
+zod@^3.17.3:
+  version "3.17.3"
+  resolved "https://registry.yarnpkg.com/zod/-/zod-3.17.3.tgz#86abbc670ff0063a4588d85a4dcc917d6e4af2ba"
+  integrity sha512-4oKP5zvG6GGbMlqBkI5FESOAweldEhSOZ6LI6cG+JzUT7ofj1ZOC0PJudpQOpT1iqOFpYYtX5Pw0+o403y4bcg==