How to change/edit a key in ConfigService - Nestjs - nestjs

I have created a Nestjs server and loading configs using .env file
ConfigModule.forRoot({
isGlobal: true,
envFilePath: [`../.env.${process.env.NODE_ENV}`, '../.env'],
}),
I have e2e test cases and need to test a condition on different values for same key in ConfigService
Is there any options to change value of a key?

Credits: Micael Levi
import { createMock, DeepMocked } from '#golevelup/ts-jest';
let mockConfigService: DeepMocked<ConfigService>
let app: INestApplication;
// Before Each
const moduleRef = await Test.createTestingModule({
providers: [
{
provide: ConfigService,
useValue: createMock<ConfigService>(),
},
],
}).compile();
app = moduleRef.createNestApplication();
// Other configs
await app.init();
mockConfigService = moduleRef.get(ConfigService)
// it(...)
jest.spyOn(mockConfigService, 'get').mockImplementation((key: string) => {
if (key === 'KEY_To_BE_MOCKED') {
return 'true';
} else {
return process.env[key];
}
});

if mocking is a headache you can always go for the "hacky" solution and manually modify the internals of the service object.
example:
config.get('someKey'); // 'original'
config.internalConfig['someKey'] = 'mockValue'; // the hacky act
config.get('someKey'); // 'mockValue'
then you can use the same object and modify it with beforeEach and afterEach or however you see fit in your tests

Related

Mock nestjs decorator

I am using a custom Firewall decorator that provides some utility functionality for many of my endpoints (e.g. throttling, authorization etc.) and I want be able to mock this decorator in my endpoints:
#Controller('some')
export class SomeController {
#Firewall() // mock it and check that it's called with correct arguments
async testEndpoint() {
return 'test';
}
}
I want to mock it and check that it's called with the correct parameters, but I can't figure out how I can do this in my test cases:
import * as request from 'supertest';
import { Test } from '#nestjs/testing';
import { INestApplication } from '#nestjs/common';
import { AppModule } from 'src/app.module';
describe('Some Controller', () => {
let app: INestApplication;
beforeAll(async () => {
const moduleRef = await Test.createTestingModule({
imports: [AppModule],
}).compile();
app = moduleRef.createNestApplication();
await app.init();
});
it('some testcase', () => {
// What do I do here to mock my Firewall decorator? // <--- <--- <---
return request(app.getHttpServer()).get('/some/testEndpoint').expect(401);
});
afterAll(async () => {
await app.close();
});
});
If it can help, here is a short version of the Firewall decorator:
import { applyDecorators } from '#nestjs/common';
import { Throttle, SkipThrottle } from '#nestjs/throttler';
export function Firewall(options?: { skipThrottle?: boolean }) {
const { skipThrottle } = options || {
anonymous: false,
};
const decorators = [];
if (skipThrottle) {
decorators.push(SkipThrottle());
} else {
decorators.push(Throttle(10, 10));
}
return applyDecorators(...decorators);
}
I have checked other answers (including this one) but they didn't help.
Thanks in advance for your time!
The #Throttle() and #SkipThrottle() decorators only apply metadata to the controller / controller method they decorate. They don't do anything on their own. Your custom #Firewall() is a utility decorator to combine these into a single decorator for convenience.
If you take a look at the source code of the nestjs/throttler package you'll see it is the #ThrottlerGuard() guard that retrieves this metadata and actually does the throttling.
I suspect you configured this one as a global app guard, so it is applied for all requests.
#Module({
imports: [
ThrottlerModule.forRoot({...}),
],
providers: [
{
provide: APP_GUARD,
useClass: ThrottlerGuard,
},
],
})
export class AppModule {}
In your test you need to mock the ThrottlerGuard.
const ThrottlerGuardMock = {
canActivate(ctx) {
const request = ctx.switchToHttp().getRequest();
// mock implementation goes here
// ...
return true;
}
} as ThrottlerGuard;
const module = await Test.createTestModule({
imports: [AppModule]
})
.overrideProvider(ThrottlerGuard)
.useValue(ThrottlerGuardMock) // <-- magic happens here
.compile();
app = moduleRef.createNestApplication();
await app.init();
You could setup some spies, in the mocked guard retrieve the metadata set by the decorators applied by the #Firewall() decorator and then invoke the spies with that metadata. Then you could just verify if the spies were called with the expected values. That would verify that your custom decorator passed down the expected values to the throttle decorators. Actually testing the #ThrottleGuard() decorator is the nestjs/throttler package's responsibility.

Nest can't resolve dependencies: NettJS Unit testing with TypeORM

i have following error when try to Unit testing with NestJS.
Nest can't resolve dependencies of the UsersService (UsersRepository, ?, UserRoleRepository, RoleRepository, JWTService). Please make sure that the argument CredentialsRepository at index [1] is available in the RootTestModule context.
test code
describe("UsersService", () => {
let service: UsersService;
let repositoryMock: MockType<Repository<Users>>;
let model: typeof Users;
let repo: Repository<Users>;
let userController: UsersController;
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
imports: [
TypeOrmModule.forRoot({
type: "mysql",
host: config.db.host,
port: config.db.port,
username: config.db.username,
password: config.db.password,
database: config.db.database,
autoLoadEntities: true,
synchronize: true,
}),
CredentialsModule,
],
providers: [
UsersService,
CredentialsService,
AuthService,
JWTService,
{
provide: getRepositoryToken(Users),
// useValue: {
// find: jest.fn(() => [Alluser]),
// },
useFactory: repositoryMockFactory,
},
],
}).compile();
service = module.get<UsersService>(UsersService);
repositoryMock = module.get(getRepositoryToken(Users));
});
it("User details get by Id", async () => {
repositoryMock.findOne.mockReturnValue(testUser);
expect(service.findUser(testUser.id)).toEqual(testUser);
expect(repositoryMock.findOne).toHaveBeenCalledWith(testUser.id);
// expect(await service.findOne(1)).toBeCalledWith(testUser);
});
// it("All Users details ", async () => {
// expect(await service.find()).toEqual([Alluser]);
// });
// it('Create new User ', async () => {
// expect(await service.createNewUser(createUser)).toEqual(testUser);
// });
});
As per the code, it seems that you are trying to test "UserService", But in the test module, you also have "CredentialsService" which is dependent on the "CredentialsRepository", and is not mocked.
providers: [
UsersService,
CredentialsService,
AuthService,
JWTService,
{
provide: getRepositoryToken(Users),
// useValue: {
// find: jest.fn(() => [Alluser]),
// },
useFactory: repositoryMockFactory,
},
],
The basic idea of unit testing is to test one block of the code, and mock the other dependencies of the code, which in this case are "CredentialsService, AuthService, and JWTService".
If the dependencies of the code will not be mocked then the real dependent code will be executed, which will call the further dependencies of the dependent code.
So to avoid those situations, you should mock "CredentialsService, AuthService, and JWTService" services as well, the way you have done for the user service, and then the reported error will be gone.
Firstly declare the variables
let credentialService: CredentialsService;
let authService: AuthService;
let jwtService: JWTService;
And then in the beforeEach block initialize those dependent services
service = module.get<UsersService>(UsersService)
credentialService = module.get<CredentialsService>(CredentialsService)
authService = module.get<AuthService>(AuthService)
jwtService = module.get<JWTService>(JWTService)

process.env's are undefined - NestJS

I've decided to write here because I've ran out of ideas. I have a NestJS app in which I use env's - nothing unusual. But something strange happens when I want to use them. I also have my own parser of these values which returns them in a convenient object - that's the first file:
env.ts
const parseStringEnv = (name: string) => {
const value: string = process.env[name];
if (!value) {
throw new Error(`Invalid env ${name}`);
}
return value;
};
const parseIntEnv = (name: string) => {
const value: string = process.env[name];
const int: number = parseInt(value);
if (isNaN(int)) {
throw new Error(`Invalid env ${name}`);
}
return int;
};
const parseBoolEnv = (name: string) => {
const value: string = process.env[name];
if (value === "false") {
return false;
}
if (value === "true") {
return true;
}
throw new Error(`Invalid env ${name}`);
};
const parseMongoString = (): string => {
const host = parseStringEnv("DATABASE_HOST");
const port = parseStringEnv("DATABASE_PORT");
const user = parseStringEnv("DATABASE_USER");
const pwd = parseStringEnv("DATABASE_PWD");
const dbname = parseStringEnv("DATABASE_NAME");
return `mongodb://${user}:${pwd}#${host}:${port}/${dbname}?authSource=admin&ssl=false`;
};
export const env = {
JWT_SECRET: parseStringEnv("JWT_SECRET"),
PORT_BACKEND: parseIntEnv("PORT_BACKEND"),
CLIENT_HOST: parseStringEnv("CLIENT_HOST"),
ENABLE_CORS: parseBoolEnv("ENABLE_CORS"),
MONGO_URI: parseMongoString(),
};
export type Env = typeof env;
I want to use it for setting port on which the app runs on and also the connection parameters for Mongoose:
In main.ts:
<rest of the code>
await app.listen(env.PORT_BACKEND || 8080);
<rest of the code>
Now, the magic starts here - the app starts just fine when ONLY ConfigModule is being imported. It will also start without ConfigModule and with require('doting').config() added. When I add MongooseModule, the app crashes because it can't parse env - and the best thing is that exception thrown has nothing to do with env's that are used to create MONGO_URI!! I'm getting "Invalid env JWT_SECRET" from my parser.
In app.module.ts
import { Module } from "#nestjs/common";
import { ConfigModule } from "#nestjs/config";
import { MongooseModule } from "#nestjs/mongoose";
import { AppController } from "./app.controller";
import { env } from "./common/env";
#Module({
imports: [
ConfigModule.forRoot({
isGlobal: true,
}),
MongooseModule.forRoot(env.MONGO_URI), //WTF?
],
controllers: [AppController],
})
export class AppModule {}
I've honestly just ran out of ideas what could be wrong. The parser worked just fine in my last project (but I haven't used Mongoose so maybe that's what causes issues). Below is my .env file template.
JWT_SECRET=
ENABLE_CORS=
PORT_BACKEND=
DATABASE_HOST=
DATABASE_PORT=
DATABASE_USER=
DATABASE_PWD
DATABASE_NAME=
CLIENT_HOST=
Thanks for everyone who has spent their time trying to help me ;)
What's happening is you're importing env.ts before the ConfigModule has imported and set the variables in your .env file.
This is why calling require('dotenv').config() works. Under the hood, that's what the ConfigModule is doing for you. However, your call to ConfigModule.forRoot is happening after you import env.ts, so the .env file hasn't been imported yet and those variables don't yet exist.
I would highly recommend you take a look at custom configuration files, which handles this for you the "Nest way":
From the Nest docs, but note that you could also use the env.ts file you already have:
// env.ts
export default () => ({
// Add your own properties here however you'd like
port: parseInt(process.env.PORT, 10) || 3000,
database: {
host: process.env.DATABASE_HOST,
port: parseInt(process.env.DATABASE_PORT, 10) || 5432
}
});
And then modify your AppModule to the following. Note that we're using the forRootAsync so that we can get a handle to the ConfigService and grab the variable from that.
// app.module.ts
import configuration from './common/env';
#Module({
imports: [
ConfigModule.forRoot({
load: [configuration],
}),
//
MongooseModule.forRootAsync({
imports: [ConfigModule],
useFactory: async (configService: ConfigService) => ({
uri: configService.get<string>('MONGO_URI'),
}),
inject: [ConfigService],
});
],
})
export class AppModule {}
As an alternative, you could also just call require('dotenv').config() inside your env.ts file at the top, but you'll miss out on all the ConfigModule helpers like dev/prod .env files.
By using registerAsync of JWT module and read process.env inside useFactory method worked for me
#Module({
imports: [
JwtModule.registerAsync({
useFactory: () => ({
secret: process.env.JWT_SECRET_KEY,
signOptions: { expiresIn: 3600 },
}),
})
],
controllers: [AppController],
})
In my case just need to replace the order import module.
import { Module } from "#nestjs/common";
import { ConfigModule } from "#nestjs/config";
import { MongooseModule } from "#nestjs/mongoose";
import { AppController } from "./app.controller";
import { env } from "./common/env"; // call process.env.xxx here > undefined
#Module({
imports: [
ConfigModule.forRoot({
isGlobal: true,
}), // process.env.xxx must be called after this line
MongooseModule.forRoot(env.MONGO_URI),
],
controllers: [AppController],
})
export class AppModule {}
so fix
import { Module } from "#nestjs/common";
import { ConfigModule } from "#nestjs/config";
// should place this at very first line
const envModule = ConfigModule.forRoot({
isGlobal: true,
})
import { MongooseModule } from "#nestjs/mongoose";
import { AppController } from "./app.controller";
import { env } from "./common/env";
#Module({
imports: [
envModule,
MongooseModule.forRoot(env.MONGO_URI),
],
controllers: [AppController],
})
export class AppModule {}
In my case I downgraded #types/node to be the same version as my node version. Could be a hint.

Jest with NestJS and async function

I'm trying to a test a async function of a service in nestJS.
this function is async... basically get a value (JSON) from database (using repository - TypeORM), and when successfully get the data, "transform" to a different class (DTO)...
the implementation:
async getAppConfig(): Promise<ConfigAppDto> {
return this.configRepository.findOne({
key: Equal("APPLICATION"),
}).then(config => {
if (config == null) {
return new class implements ConfigAppDto {
clientId = '';
clientSecret = '';
};
}
return JSON.parse(config.value) as ConfigAppDto;
});
}
using a controller, I checked that this worked ok.
Now, I'm trying to use Jest to do the tests, but with no success...
My problem is how to mock the findOne function from repository..
Edit: I'm trying to use #golevelup/nestjs-testing to mock Repository!
I already mocked the repository, but for some reason, the resolve is never called..
describe('getAppConfig', () => {
const repo = createMock<Repository<Config>>();
beforeEach(async () => {
await Test.createTestingModule({
providers: [
ConfigService,
{
provide: getRepositoryToken(Config),
useValue: repo,
}
],
}).compile();
});
it('should return ConfigApp parameters', async () => {
const mockedConfig = new Config('APPLICATION', '{"clientId": "foo","clientSecret": "bar"}');
repo.findOne.mockResolvedValue(mockedConfig);
expect(await repo.findOne()).toEqual(mockedConfig); // ok
const expectedReturn = new class implements ConfigAppDto {
clientId = 'foo';
clientSecret = 'bar';
};
expect(await service.getAppConfig()).toEqual(expectedReturn);
// jest documentation about async -> https://jestjs.io/docs/en/asynchronous
// return expect(service.getAppConfig()).resolves.toBe(expectedReturn);
});
})
the expect(await repo.findOne()).toEqual(mockedConfig); works great;
expect(await service.getAppConfig()).toEqual(expectedReturn); got a timeout => Async callback was not invoked within the 5000 ms timeout specified by jest.setTimeout;
using debug, I see that the service.getAppConfig() is called, the repository.findOne() too, but the .then of repository of findOne is never called.
Update: I'm trying to mock the repository using #golevelup/nestjs-testing, and for some reason, the mocked result don't works on service.
If I mock the repository using only jest (like code below), the test works... so, I think my real problem it's #golevelup/nestjs-testing.
...
provide: getRepositoryToken(Config),
useValue: {
find: jest.fn().mockResolvedValue([new Config()])
},
...
So, my real problem is how I'm mocking the Repository on NestJS.
For some reason, when I mock using the #golevelup/nestjs-testing, weird things happens!
I really don't found a good documentation about this on #golevelup/nestjs-testing, so, I gave up using it.
My solution for the question was to use only Jest and NestJS functions... the result code was:
Service:
// i'm injecting Connection because I need for some transactions later;
constructor(#InjectRepository(Config) private readonly configRepo: Repository<Config>, private connection: Connection) {}
async getAppConfig(): Promise<ConfigApp> {
return this.configRepo.findOne({
key: Equal("APPLICATION"),
}).then(config => {
if (config == null) {
return new ConfigApp();
}
return JSON.parse(config.value) as ConfigApp;
})
}
Test:
describe('getAppConfig', () => {
const configApi = new Config();
configApi.key = 'APPLICATION';
configApi.value = '{"clientId": "foo", "clientSecret": "bar"}';
beforeEach(async () => {
const module = await Test.createTestingModule({
providers: [
ConfigAppService,
{
provide: getRepositoryToken(Config),
useValue: {
findOne: jest.fn().mockResolvedValue(new
Config("APPLICATION", '{"clientId": "foo", "clientSecret": "bar"}')),
},
},
{
provide: getConnectionToken(),
useValue: {},
}
],
}).compile();
service = module.get<ConfigAppService>(ConfigAppService);
});
it('should return ConfigApp parameters', async () => {
const expectedValue: ConfigApp = new ConfigApp("foo", "bar");
return service.getAppConfig().then(value => {
expect(value).toEqual(expectedValue);
})
});
})
some sources utilized for this solution:
https://github.com/jmcdo29/testing-nestjs/tree/master/apps/typeorm-sample
I think expect(await repo.findOne()).toEqual(mockedConfig); works because you mocked it, so it returns right away.
In the case of expect(await service.getAppConfig()).toEqual(expectedReturn);, you did not mock it so it is probably taking more time, thus the it function returns before the Promise resolved completely.
The comments you posted from jest documentation should do the trick if you mock the call to getAppConfig().
service.getAppConfig = jest.fn(() => Promise.resolve(someFakeValue))
or
spyOn(service, 'getAppConfig').and.mockReturnValue(Promise.resolve(fakeValue))
This answer from #roberto-correia made me wonder if there must be something wrong with the way we are using createMock from the package #golevelup/nestjs-testing.
It turns out that the reason why the method exceeds the execution time has to do with the fact that createMock does not implement the mocking, and does not return anything, unless told to do so.
To make the method work, we have to make the mocked methods resolve something at the beginning of the test:
usersRepository.findOneOrFail.mockResolvedValue({ userId: 1, email: "some-random-email#email.com" });
A basic working solution:
describe("UsersService", () => {
let usersService: UsersService;
const usersRepository = createMock<Repository<User>>();
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
providers: [
UsersService,
{
provide: getRepositoryToken(User),
useValue: usersRepository,
},
}).compile();
usersService = module.get(UsersService);
});
it("should be defined", () => {
expect(usersService).toBeDefined();
});
it("finds a user", async () => {
usersRepository.findOne.mockResolvedValue({ userId: 1, email: "some-random-email#email.com" });
expect(await usersRepository.findOne()).toBe({ userId: 1, email: "some-random-email#email.com" });
});
});

Testing mongoose models with NestJS

I'm using the mongoose module from NestJS so I have my schema and an interface, and in my service I use #InjectModel to inject my model. I do not realize how I can mock the model to inject in my service.
My service looks like this:
#Injectable()
export class AuthenticationService {
constructor(#InjectModel('User') private readonly userModel: Model<User>) {}
async createUser(dto: CreateUserDto): Promise<User> {
const model = new this.userModel(dto);
model.activationToken = this.buildActivationToken();
return await model.save();
}
}
and in my service test, I have this:
const mockMongooseTokens = [
{
provide: getModelToken('User'),
useValue: {},
},
];
beforeEach(async () => {
const module: TestingModule = await Test.createTestingModule({
providers: [
...mockMongooseTokens,
AuthenticationService,
],
}).compile();
service = module.get<AuthenticationService>(AuthenticationService);
});
But when I run the test I got this error:
TypeError: this.userModel is not a constructor
I would also like to get my model to perform unit tests over it, as is shown in this article
I know this post is older but if anyone should get to this question again in the future here is an example of how to setup a mocked model and spy on any underlying query call methods. It took me longer than I wanted to figure this out but here is a full example test that doesn't require any extra factory functions or anything.
import { Test, TestingModule } from '#nestjs/testing';
import { getModelToken } from '#nestjs/mongoose';
import { Model } from 'mongoose';
// User is my class and UserDocument is my typescript type
// ie. export type UserDocument = User & Document; <-- Mongoose Type
import { User, UserDocument } from './models/user.model';
import { UsersRepository } from './users.repository';
import * as CustomScalars from '#common/graphql/scalars/data.scalar';
describe('UsersRepository', () => {
let mockUserModel: Model<UserDocument>;
let mockRepository: UsersRepository;
beforeAll(async () => {
const module: TestingModule = await Test.createTestingModule({
providers: [
{
provide: getModelToken(User.name),
useValue: Model // <-- Use the Model Class from Mongoose
},
UsersRepository,
...Object.values(CustomScalars),
],
}).compile();
// Make sure to use the correct Document Type for the 'module.get' func
mockUserModel = module.get<Model<UserDocument>>(getModelToken(User.name));
mockRepository = module.get<UsersRepository>(UsersRepository);
});
it('should be defined', () => {
expect(mockRepository).toBeDefined();
});
it('should return a user doc', async () => {
// arrange
const user = new User();
const userID = '12345';
const spy = jest
.spyOn(mockUserModel, 'findById') // <- spy on what you want
.mockResolvedValue(user as UserDocument); // <- Set your resolved value
// act
await mockRepository.findOneById(userID);
// assert
expect(spy).toBeCalled();
});
});
Understanding mongoose Model
The error message you get is quite explicit: this.userModel is indeed not a constructor, as you provided an empty object to useValue. To ensure valid injection, useValue has to be a subclass of mongoose.Model. The mongoose github repo itself gives a consistent explanation of the underlying concept (from line 63):
* In Mongoose, the term "Model" refers to subclasses of the `mongoose.Model`
* class. You should not use the `mongoose.Model` class directly. The
* [`mongoose.model()`](./api.html#mongoose_Mongoose-model) and
* [`connection.model()`](./api.html#connection_Connection-model) functions
* create subclasses of `mongoose.Model` as shown below.
In other words, a mongoose Model is a class with several methods that attempt to connect to a database. In our case, the only Model method used is save(). Mongoose uses the javascript constructor function syntax, the same syntax can be used to write our mock.
TL;DR
The mock should be a constructor function, with a save() param.
Writing the mock
The service test is the following:
beforeEach(async () => {
function mockUserModel(dto: any) {
this.data = dto;
this.save = () => {
return this.data;
};
}
const module = await Test.createTestingModule({
providers: [
AuthenticationService,
{
provide: getModelToken('User'),
useValue: mockUserModel,
},
],
}).compile();
authenticationService = module.get<AuthenticationService>(AuthenticationService);
});
I also did a bit of refactoring, to wrap everything in the beforeEach block.
The save() implementation I chose for my tests is a simple identity function, but you can implement it differently, depending on the way you want to assert on the return value of createUser().
Limits of this solution
One problem with this solution is precisely that you assert on the return value of the function, but cannot assert on the number of calls, as save() is not a jest.fn(). I could not find a way to use module.get to access the Model Token outside of the module scope. If anyone finds a way to do it, please let me know.
Another issue is the fact that the instance of userModel has to be created within the tested class. This is problematic when you want to test findById() for example, as the model is not instantiated but the method is called on the collection. The workaround consists in adding the new keyword at the useValue level:
const module = await Test.createTestingModule({
providers: [
AuthenticationService,
{
provide: getModelToken('User'),
useValue: new mockUserModel(),
},
],
}).compile();
One more thing...
The return await syntax should not be used, as it raises a ts-lint error (rule: no-return-await). See the related github doc issue.
in response to #jbh solution, a way to resolve the problem of not instanciating the class in a call of a method like findById() is to use static methods, you can use like that
class mockModel {
constructor(public data?: any) {}
save() {
return this.data;
}
static findOne({ _id }) {
return data;
}
}
mockModel.findOne();
More info about static methods: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static
beforeAll(async () => {
const app: TestingModule = await Test.createTestingModule({
controllers: [UserController],
providers: [
// THIS IS MOCK FOR OUT TEST-APP, MODULE...
{
provide: getModelToken(User.name),
useValue: {},
},
UserService, // SUPPOSE THESE PROVIDERS ALSO NEED OUR USER-MODEL
HealthService, // SO THEY ARE SIBLINGS FOR OUT USER-MODEL
],
imports: [UserModule],
}) // SO IN THIS PLACE WE MOCK USER-MODEL AGAIN
.overrideProvider(getModelToken(User.name)) // <-----
.useValue({}) // <-----
.compile();
});
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