Cannot stub non-existent property "create" of a mongoose document - node.js

I'm writing unit tests for my express app using Sinon. I have a Log model:
import { Schema, model } from 'mongoose';
const LogSchema = new Schema({
content: {
type: String,
required: true,
},
date: {
type: Date,
default: Date.now,
},
});
const Log = model('Log', LogSchema);
export default Log;
And a LogController:
import Log from '../models/Log';
class LogController {
static async create(content) {
await Log.create({ content });
}
}
export default LogController;
I'm trying to write tests for LogController.create().
import { createSandbox } from 'sinon';
import Log from '../../../src/models/Log';
import LogController from '../../../src/controllers/LogController';
describe('LogController', () => {
let sandbox;
let createStub;
beforeEach(() => {
sandbox = createSandbox();
createStub = sandbox.stub(Log, 'create');
});
describe('create()', () => {
it('should create a Log with the given content', async () => {
await LogController.create('Bob Lob Law is on the house');
expect(createStub.calledWith({ content: 'Bob Lob Law is on the house' })).to.be.true;
});
});
But then I get TypeError: Cannot stub non-existent property create, implying that Log doesn't have a create method. Which is weird, since I have other controllers that are tested exactly like this and they don't throw any error. I also tried stubbing it with Log.create = sandbox.stub() but I got the same error. Maybe I'm doing something wrong on my model definition? How can I fix this?

Sinon thinks you're trying to stub object.create for some reason (instead of model.create) possibly because model.create returns a promise, but your stub doesn't return anything. You need to change
createStub = sandbox.stub(Log, 'create');
to
createStub = sandbox.stub(Log, 'create').resolves();

Related

How to test Validation pipe is throwing the expect error for improperly shaped request on NestJS

I'm using NestJS 7.0.2 and have globally enabled validation pipes via app.useGlobalPipes(new ValidationPipe());.
I'd like to be able to have a unit test that verifies that errors are being thrown if the improperly shaped object is provided, however the test as written still passes. I've seen that one solution is to do this testing in e2e via this post, but I'm wondering if there is anything I'm missing that would allow me to do this in unit testing.
I have a very simple controller with a very simple DTO.
Controller
async myApi(#Body() myInput: myDto): Promise<myDto | any> {
return {};
}
DTO
export class myDto {
#IsNotEmpty()
a: string;
#IsNotEmpty()
b: string | Array<string>
}
Spec file
describe('generate', () => {
it('should require the proper type', async () => {
const result = await controller.generate(<myDto>{});
// TODO: I expect a validation error to occur here so I can test against it.
expect(result).toEqual({})
})
})
It also fails if I do not coerce the type of myDto and just do a ts-ignore on a generic object.
Just test your DTO with ValidationPipe:
it('validate DTO', async() => {
let target: ValidationPipe = new ValidationPipe({ transform: true, whitelist: true });
const metadata: ArgumentMetadata = {
type: 'body',
metatype: myDto,
data: ''
};
await target.transform(<myDto>{}, metadata)
.catch(err => {
expect(err.getResponse().message).toEqual(["your validation error"])
})
});
You can find here complete test examples for ValidationPipe in Nestjs code repository
To test custom ValidationPipe:
let target = new ValidationDob();
const metadata: ArgumentMetadata = {
type: 'query',
metatype: GetAgeDto,
data: '',
};
it('should throw error when dob is invalid', async () => {
try {
await target.transform(<GetAgeDto>{ dob: 'null' }, metadata);
expect(true).toBe(false);
} catch (err) {
expect(err.getResponse().message).toEqual('Invalid dob timestamp');
}
});

Mongoose - multiple database connections

I want to understand how to switch between databases within mongoose global promise connection.
My current connection is established this way app.ts
import * as mongoose from 'mongoose';
...
try {
await mongoose.createConnection(`mongodb://localhost:27017/db1`, {
useNewUrlParser: true,
})
console.log("Connected")
} catch (error) {
console.log(error)
}
And then I am accessing it in different files some.model.ts
import { Schema, Document, model } from 'mongoose';
const SomeSchema: Schema = new Schema({
name: { type: String, required: true },
owner: { type: string, required: true }
});
export default model('Some', SomeSchema);
According to documentation.
So far we've seen how to connect to MongoDB using Mongoose's default connection. At times we may need multiple connections open to Mongo, each with different read/write settings, or maybe just to different databases for example. In these cases we can utilize mongoose.createConnection() which accepts all the arguments already discussed and returns a fresh connection for you.
const conn = mongoose.createConnection('mongodb://[username:password#]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]', options);
I can create multiple database connections like this
try {
const db1 = await mongoose.createConnection(`mongodb://localhost:27017/db1`, {
useNewUrlParser: true,
})
const db2 = await mongoose.createConnection(`mongodb://localhost:27017/db2`, {
useNewUrlParser: true,
})
console.log("Connected")
} catch (error) {
console.log(error)
}
I can see both connection in console.log(mongoose.connections)
But how can I specify what database should be used for the Model in some.model.ts?
import { Schema, Document, model } from 'mongoose';
const SomeSchema: Schema = new Schema({
name: { type: String, required: true },
owner: { type: string, required: true }
});
export default SPECIFY_DATABASE.model('Some', SomeSchema);
I have found other questions like this but there are connections created "localy", I need to use mongoose connection across many different files.
Thank you for answers, if you need more explanation please let me now.
You need to actually return the connection, and then register a given model to each of the connections. To clarify, you need:
something to create a (named, specific) connection
schemas
you create models by registering schemas to the given connections,
you also need something to orchestrate it.
Example, lets have a "db.js" file (I call mine "repo.js" usually) with a single export, a function that returns the initialized database Promise.
You'd use it by importing the function and awaiting for the db.
I have a bit of a longer example, so error handling etc is ommited for brevity.
import { createConnections } from './create-connections';
import { UsersSchema } from './users-schema';
import { PostsSchema } from './posts-schema';
let db: any;
export function getDatabase(): Promise<any> {
if (this.db) return Promise.resolve(db);
return createDatabases();
}
async function createDatabases() {
const { db1, db2 } = await createConnections('mongodb://localhost/db1', 'mongodb://localhost/db2');
const UserModel = db1.model('users', UserSchema);
const PostModel = db2.model('posts', PostSchema);
db = {
UserModel,
PostModel,
// also if you need this
connections: {
db1,
db2,
}
}
return db;
}
Now, I've used './create-connections' here, which is almost what you have:
// create-connection.js
const { createConnection } = require('mongoose');
// You create connections by calling this function and giving it the URL to the server
export function createConnections(url1, url2) {
const db1 = await createConnection(url1);
const db2 = await createConnection(url2);
return {
db1,
db2
}
}
Now, let's say you have two models: users and posts, let's have their schemas.
// users schema
import { Schema, Document } from 'mongoose';
export const UserSchema: Schema = new Schema({
name: { type: String, required: true },
});
// posts schema
import { Schema, Document } from 'mongoose';
export const PostSchema: Schema = new Schema({
text: { type: String, required: true },
owner: { type: SchemaID, required: true }
});
So now you need to bind it all in that fdirst file.
But how to use it? As I've said, since it's async, you always import it and use it as a simple async getDB:
// some controller, route handler, service etc.
import { getDatabase } from './get-database';
router.get('/users', async (req, res) => {
const User = await getDatabase().UserModel;
const users = await User.find();
return res.json(users);
});
router.post('/posts', async (req, res) {
const { text } = req.body;
const owner = req.user.id;
const Post = await getDatabase().PostModel;
const post = await Post.create({ text, owner });
return res.json(post);
});

Mocking mongoose validators with jest

I'm testing a mongoose model's validation, while trying to mock a validator, the model still has the reference to the original function, so the validation keeps calling the original function.
I want to test that the validator function get's called, however since the validator goes to the db I need to mock it.
This is my model:
const { hasRequiredCustoms } = require('../utils/validators')
const ProductSchema = new Schema({
customs: {
type: [String],
validate: hasRequiredCustoms // <- This is the validator
}
})
const Product = mongoose.model('Product', ProductSchema)
module.exports = Product
The original validators:
module.exports = {
hasRequiredCustoms(val) {
console.log('Original')
// validation logic
return result
},
//etc...
}
This is the mock for validators:
const validators = jest.genMockFromModule('../validators')
function hasRequiredCustoms (val) {
console.log('Mock')
return true
}
validators.hasRequiredCustoms = hasRequiredCustoms
module.exports = validators
And the test:
test('Should be invalid if required customs missing: price', done => {
jest.mock('../../utils/validators')
function callback(err) {
if (!err) done()
}
const m = new Product( validProduct )
m.validate(callback)
})
Every time I run the tests the console logs the Original. Why is the reference still going back to the original module? seems like I'm missing some super essential concept of how require works or the way mongoose stores the validators references.
Thanks for the help.

Mocking Mongoose model with jest

I am trying to mock a mongoose model with jest, but is getting Cannot create property 'constructor' on number '1' error. I was able to reproduce the issue by creating the project with 2 files shown below. Is there a way to mock a mongoose model with jest?
./model.js
const mongoose = require('mongoose')
const Schema = mongoose.Schema
const schema = new Schema({
name: String
})
module.exports = mongoose.model('Test', schema)
./model.test.js
jest.mock('./model')
const Test = require('./model')
// Test.findOne.mockImplementation = () => {
// ...
// }
Error:
FAIL ./model.test.js
● Test suite failed to run
TypeError: Cannot create property 'constructor' on number '1'
at ModuleMockerClass._generateMock (../../jitta/sandbox/rest_api/node_modules/jest-mock/build/index.js:458:34)
at Array.forEach (native)
at Array.forEach (native)
at Array.forEach (native)
Update:
Seems to be a bug in jest.
https://github.com/facebook/jest/issues/3073
An other solution is to spyOn the model prototype functions.
For example, this will make MyModel.save() fail :
jest.spyOn(MyModel.prototype, 'save')
.mockImplementationOnce(() => Promise.reject('fail update'))
You can use mockImplementationOnce to not having to mockRestore the spy. But you can also use mockImplementation and use something like :
afterEach(() => {
jest.restoreAllMocks()
})
Tested with "mongoose": "^4.11.7" and "jest": "^23.6.0".
ok, i had the same problem so i author this package to solve this problem:
https://www.npmjs.com/package/mockingoose
this is how you can use it let's say this is your model:
import mongoose from 'mongoose';
const { Schema } = mongoose;
const schema = Schema({
name: String,
email: String,
created: { type: Date, default: Date.now }
})
export default mongoose.model('User', schema);
and this is your test:
it('should find', () => {
mockingoose.User.toReturn({ name: 2 });
return User
.find()
.where('name')
.in([1])
.then(result => {
expect(result).toEqual({ name: 2 });
})
});
checkout the tests folder for more examples:
https://github.com/alonronin/mockingoose/blob/master/___tests___/index.test.js
no connections is made to the database!
for typescript I found a hack that works
jest.spyOn(model, 'find').mockReturnValueOnce(dummyData as any);
Mockingoose seems to be a very nice solution. But I was also able to mock my model with Jest.mock() function. At least create method.
// in the module under the test I am creating (saving) DeviceLocation to DB
// someBackendModule.js
...
DeviceLocation.create(location, (err) => {
...
});
...
DeviceLocation model definition:
// DeviceLocation.js
import mongoose from 'mongoose';
const { Schema } = mongoose;
const modelName = 'deviceLocation';
const DeviceLocation = new Schema({
...
});
export default mongoose.model(modelName, DeviceLocation, modelName);
DeviceLocation mock in the __mocks__ folder in the same folder as DeviceLocation model:
// __mock__/DeviceLocation.js
export default {
create: (x) => {
return x;
},
};
in the test file:
// test.js
// calling the mock
...
jest.mock('../../src/models/mongoose/DeviceLocation');
import someBackendModule from 'someBackendModule';
...
// perform the test

GraphQL with express error : Query.example field type must be Output Type but got: [object Object]

I'm trying to run express server with graphql and I get the following error:
Error: Query.example field type must be Output Type but got: [object Object].
express-graphql used in a route:
app.use('/graphql', graphqlHTTP(req => ({
schema,
pretty: true
})));
The schema looks like that:
export default new GraphQLSchema({
query: new GraphQLObjectType({
name: 'Query',
fields: queries
})
});
Queries has only one query that imported from here:
import {
GraphQLList,
GraphQLID,
GraphQLNonNull
} from 'graphql';
import exampleScheme from '../models/schemes/example';
import {example as exampleData} from '../models/jsons'
export default {
type: exampleScheme,
resolve (root, params, options) {
return exampleData;
}
};
The schemas (exampleScheme) and data (exampleScheme) are working on another project so I assume they're not the problem.
Any ideas? What does 'Output type' mean?
if
export default {
type: exampleScheme,
resolve (root, params, options) {
return exampleData;
}
};
is your queries, then you got it wrong,
Query's fields, hence queries in your example, should be looking like this:
export default {
helloString: {
type: GraphQLString,
resolve (root, params, options) {
return "Hello World!";
}
}
... <Next query>
};
anyway, the error is that 'type' is not a valid GraphQLType.
then the query will look like this
query {
testString
}
will result in:
{
testString: "Hello World!"
}
if the meaning was that the exampleScheme is some other object,
please make sure you are creating it using:
new GraphQLObjectType({ .... Options });
Hope it helps! :)

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