nifty_lil_tricks_testing/plugin_nestjs

Note: this package is currently a work in progress

A nifty li'l plugin for setting up PostgreSQL database instances when testing

Installation

Note: this package works with TypeScript v5 or later

Deno

import { nestJsPlugin } from "@nifty-lil-tricks/testing-plugin-nestjs";

Node.js

npm install @nifty-lil-tricks/testing-plugin-nestjs

TypeScript

The TypeScript tsconfig.json must contain the following recommended settings:

{
  "compilerOptions": {
    "target": "ES2022",
    "strict": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true
  }
}

Features

The following features are supported:

• Setup a NestJS server for testing.
• Override the NestJS server providers.
• Override the NestJS server modules.

Quick start

Setup a NestJS server as follows:

// Copyright 2023-2023 the Nifty li'l' tricks authors. All rights reserved. MIT license.

import { assertEquals } from "testing/asserts.ts";
import {
  afterEach,
  beforeEach,
  describe,
  it,
} from "testing/bdd.ts";
import {
  setupTestsFactory,
  type SetupTestsTeardown,
} from "@nifty-lil-tricks/testing";
import {
  nestJsPlugin,
  type PluginConfig,
} from "@nifty-lil-tricks/testing-plugin-nestjs";
import { Controller, Get, Module } from "npm:@nestjs/common@^10.2.7";

// In another file, load plugins as follows to generate a setupTests function:
const { setupTests } = setupTestsFactory({ server: nestJsPlugin });

// In another file, define a NestJS app as follows:

@Controller()
export class BasicAppController {
  @Get("/hello")
  getHello(): string {
    return "Hello, world!";
  }
}

@Module({
  imports: [],
  controllers: [BasicAppController],
})
export class BasicAppModule {}

// Then one can use this in any test file as follows:
describe("Service", () => {
  let teardownTests: SetupTestsTeardown;
  let origin: string;

  beforeEach(async () => {
    // Setup tests with configured plugins
    const result = await setupTests({
      server: {
        appModule: BasicAppModule,
      } as PluginConfig,
    });
    teardownTests = result.teardownTests;
    origin = result.outputs.server.output.origin;
  });

  afterEach(async () => {
    // Teardown tests to restore environment after tests have run
    await teardownTests();
  });

  describe("method", () => {
    it("should test something that relies on the nestjs plugin", async () => {
      // Arrange & Act
      const response = await fetch(new URL("/hello", origin));

      // Assert
      assertEquals(response.status, 200);
      assertEquals(await response.text(), "Hello, world!");
    });
  });
});

With overrides

One can also use define a NestJS app with testing overrides to allow one to mock out dependencies where needed. For example, module overrides:

// Copyright 2023-2023 the Nifty li'l' tricks authors. All rights reserved. MIT license.

import { assertEquals } from "testing/asserts.ts";
import {
  afterEach,
  beforeEach,
  describe,
  it,
} from "testing/bdd.ts";
import {
  setupTestsFactory,
  type SetupTestsTeardown,
} from "@nifty-lil-tricks/testing";
import {
  nestJsPlugin,
  type PluginConfig,
} from "@nifty-lil-tricks/testing-plugin-nestjs";
import { Controller, Get, Module } from "npm:@nestjs/common@^10.2.7";

// In another file, load plugins as follows to generate a setupTests function:
const { setupTests } = setupTestsFactory({ server: nestJsPlugin });

// In another file, define a NestJS app as follows:

@Controller()
export class BasicAppController {
  @Get("/hello")
  getHello(): string {
    return "Hello, world!";
  }
}

@Module({
  imports: [],
  controllers: [BasicAppController],
})
export class BasicAppModule {}

// In another file, define a NestJS app overrides for testing as follows:
@Controller()
class NewAppController {
  @Get("/hello")
  getHello(): string {
    return "Ahoy!";
  }
}
@Module({
  controllers: [NewAppController],
})
class NewModule {}

// Then one can use this in any test file as follows:
describe("Service", () => {
  let teardownTests: SetupTestsTeardown;
  let origin: string;

  beforeEach(async () => {
    // Setup tests with configured plugins
    const result = await setupTests({
      server: {
        appModule: BasicAppModule,
        modules: [{
          moduleToOverride: BasicAppModule,
          newModule: NewModule,
        }],
      } as PluginConfig,
    });
    teardownTests = result.teardownTests;
    origin = result.outputs.server.output.origin;
  });

  afterEach(async () => {
    // Teardown tests to restore environment after tests have run
    await teardownTests();
  });

  describe("method", () => {
    it("should test something that relies on the nestjs plugin", async () => {
      // Arrange & Act
      const response = await fetch(new URL("/hello", origin));

      // Assert
      assertEquals(response.status, 200);
      assertEquals(await response.text(), "Ahoy!");
    });
  });
});

API

The API Docs can be found here.

Examples

Examples can be found here.

Support

Platform Version	Supported	Notes
Deno v1	✅
Node.JS v18	✅	TypeScript v5+ for typings
Node.JS v20	✅	TypeScript v5+ for typings
Web Browsers	❌	Coming soon

Useful links

• For help or feedback on this project, join us in GitHub Discussions

License

Nifty li'l tricks nestjs package is 100% free and open-source, under the MIT license.

This package is Treeware. If you use it in production, then we ask that you buy the world a tree to thank us for our work. By contributing to the Treeware forest you’ll be creating employment for local families and restoring wildlife habitats.

Contributions

Contributions, issues and feature requests are very welcome. If you are using this package and fixed a bug for yourself, please consider submitting a PR!