Jest template for Backend Services that connects to Mock MongoDB
Step 1. Jest config file within the package
Provide the related jest configuration and mock mongo configuration.
Here are relative path (../../../) is based on the package related to the root.
const base = require('../../../jest.config.base');
const packageJson = require('./package');
const merge = require('merge')
const baseConfig = require('../../../jest.config.base');
const mongodbConfig = require('../../../jest.config.mongodb');
const mergeData = merge.recursive(
baseConfig,
{
"transform": {
"\\.(js|jsx)?$": "../../../transform.js",
},
moduleNameMapper: {
'^__mocks__/(.*)$': '<rootDir>/../../__mocks__/$1',
// we'll use commonjs version of lodash for tests 👌
// because we don't need to use any kind of tree shaking right?!
'^lodash-es$': '<rootDir>/../../../node_modules/lodash/index.js',
'@adminide-stack\/core': '<rootDir>/../../adminide-core/src/index.ts',
},
roots: [
"src",
],
},
mongodbConfig,
{
globals: {
}
}
);
module.exports = mergeData;
Step 2. Make sure you have test.env file under config/test
You can copy the existing dev.env values in test.env unless you want to modify anything based on your testing need.
Step 3. Create test file like AccountService.test.ts within the same folder where you have AccountService.ts
import 'reflect-metadata';
import * as MongoDB from 'mongodb';
import { connection as mongooseConnection } from 'mongoose';
import mongoose from 'mongoose';
import { config } from 'dotenv';
import { logger } from '@cdm-logger/server';
import { AccountRepository } from '../../store/repositories/account-repository';
import { AccountService } from './account-service';
import * as data from './fixtures/account-fixture.json';
config({ path: process.env.ENV_FILE });
// needed for all test cases
async function dropAllCollections() {
const collections = Object.keys(mongooseConnection.collections);
for (const collectionName of collections) {
const collection = mongooseConnection.collections[collectionName];
try {
await collection.drop();
} catch (error) {
// Sometimes this error happens, but you can safely ignore it
if (error.message === 'ns not found') return;
// This error occurs when you use it.todo. You can
// safely ignore this error too
if (error.message.includes('a background operation is currently running')) return;
console.log(error.message);
}
}
}
describe('test Create/Update/Delete Account Service', () => {
let db: MongoDB.Db;
let connection: MongoDB.MongoClient;
let accountRepo: AccountRepository;
let accountService: AccountService;
beforeAll(async () => {
const conn = mongoose.createConnection(process.env.MONGO_URL, { dbName: 'jest' });
accountRepo = new AccountRepository(conn, logger);
accountService = new AccountService(logger, accountRepo);
});
afterAll(async () => {
await dropAllCollections();
connection.close();
});
it('service ', async() => {
await accountRepo.create(data);
const result = await accountRepo.getAll({});
........
});
});