Node Mocha & Supertest: Error: ECONNREFUSED: Connection refused - node.js

Question

I have built an api and i want to test some of the endpoints.
I have a number of tests that are similar to the ones below. They are all all failing because of Error: ECONNREFUSED: Connection refused
tests
import { assert, expect } from "chai";
import request from "supertest";
import app from "./../src/index";
describe("Authentication", () => {
it("should respond with 200 product_id is authorised", async () => {
const result = await request(app).post("/api/auth")
.send({
product_id: "123",
origin: "localhost:3000",
})
.expect("Content-Type", /json/)
.expect(200);
});
it("should respond with session token", async () => {
const result = await request(app).post("/api/auth")
.send({
product_id: "123",
origin: "localhost:3000",
});
expect(result.body.data).to.have.property("token");
});
});
package.json
"test": "mocha -r ts-node/register --project tsconfig.json test/*.test.ts --exit"
errors:
> mocha -r ts-node/register --project tsconfig.json test/*.test.ts --exit
Server Running On: runner-sefsf-project-41-concurrent-0gdrs7:3000
Authentication
MongoDB Successfully Connected On: mongodb://localhost:27017/p
1) should respond with 200 product_id is authorised
2) should respond with p session token
Server
3) should be up
4) should throw 404 for unrecognized routes
Transaction
5) should respond with a new transction
0 passing (40ms)
5 failing
1) Authentication
should respond with 200 product_id is authorised:
Error: ECONNREFUSED: Connection refused
at Test.assert (node_modules/supertest/lib/test.js:165:15)
at assert (node_modules/supertest/lib/test.js:131:12)
at /eng/p-server/node_modules/supertest/lib/test.js:128:5
at Test.Request.callback (node_modules/superagent/lib/node/index.js:718:3)
at ClientRequest.req.once.err (node_modules/superagent/lib/node/index.js:646:10)
at Socket.socketErrorListener (_http_client.js:382:9)
at emitErrorNT (internal/streams/destroy.js:82:8)
at emitErrorAndCloseNT (internal/streams/destroy.js:50:3)
at process._tickCallback (internal/process/next_tick.js:63:19)
2) Authentication
should respond with p session token:
Error: ECONNREFUSED: Connection refused
at Test.assert (node_modules/supertest/lib/test.js:165:15)
at assert (node_modules/supertest/lib/test.js:131:12)
at /eng/p-server/node_modules/supertest/lib/test.js:128:5
at Test.Request.callback (node_modules/superagent/lib/node/index.js:718:3)
at ClientRequest.req.once.err (node_modules/superagent/lib/node/index.js:646:10)
at Socket.socketErrorListener (_http_client.js:382:9)
at emitErrorNT (internal/streams/destroy.js:82:8)
at emitErrorAndCloseNT (internal/streams/destroy.js:50:3)
at process._tickCallback (internal/process/next_tick.js:63:19)
Apparently the connection is being refused? But i'm not sure what it means by this specifically because you can see the server in the error log is connected and so is the mongo service.
index.ts
import Server from "./server";
export default new Server().server;
server.ts
import App from "./app";
class Server {
public server: any;
private instance: any;
private app: any;
private config: any;
constructor() {
this.instance = new App();
this.app = this.instance.app;
this.config = this.instance.config;
this.server = this.app.listen(this.config.port, this.config.hostname);
console.log("Server Running On: " + this.config.hostname + ":" + this.config.port);
}
}
export default Server;

Answer 1

Make sure your server is stopped before you run the test case using supertest as supertest run the api in that same port. So, you need to make that port free for use by supertest.
Since you are using this in your test file,
import request from "supertest";
import app from "./../src/index";
The app contains the domain URL like http://localhost:3135 and when you call the api like, request(app).post where request refers to the supertest module, you always need to make sure that the app is free. Which means, request('http://localhost:3135').post works when there is no process running on port 3135.
You can check the node running processes using pidof node (in linux)and kill every process to make sure the port is available or kill process for that specific port.

Answer 2

I encountered the same error and spend a couple of hours trying to figure out what was up. I was using the pg library and so it happens it needs to pick db options from the environment variables. My problem was I was calling dotenv.config() at the wrong place.