Golang Integration Testing Example

This repository accompanies the article Integration Testing in Go with Testcontainers and demonstrates how to build a simple CRUD application in Golang with robust testing practices. The project covers unit testing and integration testing against real infrastructure using Docker and Testcontainers.

Features

• Create, Read, Update, Delete (CRUD) operations for notes with an id, title and description.
• Layered architecture:
  • Database Access Layer (DBAL): Handles all database interactions using pgx.
  • Service Layer: Contains business logic.
  • HTTP Layer: Exposes REST API endpoints.
• Integration tests with real PostgreSQL using Testcontainers.
• Unit tests with mocked dependencies.

Prerequisites

• Go 1.20 or higher.
• Docker.
• make (optional, for running migrations).
• PostgreSQL (if running outside Docker).

Getting Started

1. Clone the repository

git clone https://github.com/the-code-genin/golang_integration_testing.git
cd golang_integration_testing

2. Initialize Go modules

go mod download

3. Set up PostgreSQL

(Optional) Using Docker:

docker run -p 5432:5432 -e POSTGRES_PASSWORD=password -d postgres:16.11

Running migrations:

make migrate-up

This ensure we have a database with all migrations applied.

4. Running the Server

Start the application:

go run .

The server should start on port 8080 (or the port specified via env variables):

# [GIN-debug] Listening and serving HTTP on :8080

Project Structure

• migrations/ - SQL migration files.
• repository/ - Database Access Layer (DBAL).
• service/ - Business logic layer.
• http/ - REST API layer.
• tests/- Test helpers.
• main.go- Application entry point.
• Makefile - Optional automation commands.

API Endpoints

• POST /notes - Create a note with title and description.
• GET /notes/:id - Fetch a single note by ID.
• GET /notes - Fetch all notes.
• PUT /notes/:id - Update a note by ID.
• DELETE /notes/:id - Delete a note by ID.