Go Template Project

Overview

Fork for quick creation of new Go applications. It includes a structured directory layout with a Makefile for build automation, envconfig for environment configuration/management, Zap and lumberjack for structured logging with rotation and retention, OpenTelemetry for observability and tracing, Prometheus for metrics collection and monitoring. Includes a Dockerfile and docker-compose.yaml for containerization. Contains a basic HTTP Gin server with health check and Swagger documentation, with additional integrations for Kafka, Postgres, MongoDB, and Redis.

Getting Started

Prerequisites

• Go 1.21 (specified in go.mod)
• make installed
• Docker (optional)

Setup

1. Clone the Repository

   git clone <repository-url>
   cd <repository-name>

2. Install Dependencies

   Install the project dependencies using go mod:

   cd goapp
   go mod tidy

3. Rename the Application

   Update the application name using the rename_app.sh script.

   ./rename_app.sh <old_app_name> <new_app_name>
   # Example
   ./rename_app.sh goapp myapp

4. Set Up Environment Variables

   Ensure that required environment variables are set. Refer to the .env.example file for reference.

Makefile Targets

The Makefile in the root of the project provides a set of commands to help with building, running, and managing the application. Running make first will set up your project by creating necessary files and installing dependencies.

Setup

• first: Performs an initial setup by:
  • Creating the .env file if it doesn’t exist.
  • Installing Swaggo for Swagger documentation.
  • Generating Swagger documentation.
  • Building the application.
  • Running the application.

Environment Management

• env: Checks for the .env file and creates it if missing.

Swagger Documentation

• swaggo: Installs the Swaggo tool for generating Swagger documentation.
• swagger: Generates Swagger documentation from the codebase.

Build

• build: Builds the application binary defaults to MacOS.
• build-verbose: Builds the application with verbose output.
• build-linux: Builds the application for Linux.
• build-windows: Builds the application for Windows.
• build-race: Builds the application with race detector enabled.

Run

• run: Runs the built application binary, stored in the build directory.

Docker Management

• docker-recycle: Recycles Docker containers using the docker-recycle.sh script, located in the root of the project.
• docker-exec: Executes a shell in the Docker container.

Miscellaneous

• tidy: Tidy will clean up the Go module cache in the Go module directory.
• monitors: Starts the monitoring stack with Prometheus and Grafana.

Running make first is recommended to get your project set up and ready for development.

Docker

To run the application in Docker:

docker-compose up --build

Attach a shell to the container:

docker run -it --entrypoint /bin/sh go-app

File Structure

> tree
.
├── Dockerfile
├── Makefile
├── README.md
├── assets
│   └── certs
├── docker-compose.yaml
├── docker-recycle.sh
├── goapp
│   ├── api
│   │   ├── handlers
│   │   │   └── health.go
│   │   └── routes
│   │       └── routes.go
│   ├── build
│   │   └── goapp
│   ├── cmd
│   │   └── goapp
│   │       └── main.go
│   ├── docs
│   │   ├── docs.go
│   │   ├── swagger.json
│   │   └── swagger.yaml
│   ├── go.mod
│   ├── go.sum
│   ├── internal
│   │   └── config
│   │       └── config.go
│   ├── pkg
│   │   ├── clients
│   │   │   └── clients.go
│   │   ├── db
│   │   │   ├── kafka
│   │   │   │   ├── example.go
│   │   │   │   ├── kafka.go
│   │   │   │   └── model.go
│   │   │   └── postgres
│   │   │       ├── example.go
│   │   │       ├── model.go
│   │   │       └── postgres.go
│   │   ├── logging
│   │   │   ├── logging.go
│   │   │   └── model.go
│   │   └── otel
│   │       └── otel.go
│   ├── scripts
│   ├── tests
│   │   ├── helpers
│   │   └── unit
│   └── web
│       ├── static
│       └── templates
├── logs
│   └── app.log
├── monitoring
│   ├── datasources
│   │   └── datasources.yaml
│   ├── docker-compose.yaml
│   └── prometheus.yaml
└── rename_app.sh

30 directories, 30 files

Directory Overview

• api: Contains the HTTP handlers and routes.
• build: Build artifacts.
• cmd: Main applications for the project.
• docs: Documentation including Swagger.
• internal: Internal application code.
• pkg: Library code to be used by external applications.
  • db/kafka: Kafka integration.
  • db/postgres: PostgreSQL integration.
  • logging: Logging setup.
  • otel: OpenTelemetry setup.
• scripts: Scripts for various tasks.
• tests: Unit and helper tests.
• web: Web assets like static files and templates.
• logs: Application logs.
• monitoring: Monitoring setup for Grafana and Prometheus.

Environment Variables

The application uses envconfig to manage environment variables. Ensure the following variables are set:

• Kafka:

  • KAFKA_BROKERS
  • KAFKA_PRODUCER_TOPIC
  • KAFKA_CONSUMER_TOPIC
  • KAFKA_CONSUMER_GROUP
  • KAFKA_CONSUMER_OFFSET

• Postgres:

  • DB_HOST
  • DB_PORT
  • DB_USER
  • DB_PASSWORD
  • DB_NAME
  • DB_SSL_MODE

• Prometheus:

  • PROMETHEUS_PORT

Logging

The application uses Zap for structured logging with log rotation and retention. Logs are written to app.log and error.log in the logs directory.

Monitoring

Prometheus is used for metrics collection and Grafana for visualization. The monitoring setup is available in the monitoring directory, just run docker compose up to start the monitoring stack which includes a single Prometheus instance and a Grafana instance. The Prometheus configuration is available in monitoring/prometheus.yaml, and the Grafana datasource configuration to pull metrics from Prometheus is available in monitoring/datasources/datasources.yaml.