Chirpy - A Twitter-Like API Service

Overview

Chirpy is a backend API service built with Go that provides core functionality similar to Twitter/X. Users can create accounts, post short messages (chirps), and interact with other users' content. The service includes JWT-based authentication, database persistence, and various API endpoints to manage users and chirps.

Features

Authentication System

• User registration and login
• JWT-based access tokens
• Refresh token system for prolonged sessions
• Token revocation

User Management

• Create user accounts
• Update user profiles
• Premium (Chirpy Red) subscription support

Chirp Functionality

• Create chirps (140 character limit)
• List chirps with sorting and filtering
• Delete chirps (author-only)
• Profanity filtering

Admin Features

• Usage metrics
• Database reset (development mode only)

Webhook Integration

• Support for Polka payment service integration
• User subscription status updates

Technical Stack

• Backend: Go
• Database: PostgreSQL
• ORM: SQLC for type-safe SQL
• Migration: Goose
• Authentication: JWT
• Configuration: Environment variables via godotenv

More About Development Tools

SQLC Commands

Installing sqlc CLI tools with go install

go install github.com/sqlc-dev/sqlc/cmd/sqlc@latest

SQLC generates type-safe Go code from SQL queries. Before using SQLC, you need to create a configuration file named sqlc.yaml in your project root:

version: "2"
sql:
  - schema: "sql/schema"
    queries: "sql/queries"
    engine: "postgresql"
    gen:
      go:
        out: "internal/database"

# Generate Go code from SQL queries
sqlc generate

# Verify SQL queries without generating code
sqlc vet

Example SQLC query definition:

-- name: GetUserByEmail :one
SELECT * FROM users
WHERE email = $1;

Tutorial : https://docs.sqlc.dev/en/latest/tutorials/getting-started-postgresql.html

Gooose Migrations

Installing goose CLI tools with go install

go install github.com/pressly/goose/v3/cmd/goose@latest

Goose handles database schema migrations.

# Create a new migration
goose -dir sql/schema create add_users_table sql

# Apply migrations
goose -dir sql/schema postgres "postgresql://user:password@localhost:5432/chirpy?sslmode=disable" up

# Roll back the most recent migration
goose -dir sql/schema postgres "postgresql://user:password@localhost:5432/chirpy?sslmode=disable" down

# Check migration status
goose -dir sql/schema postgres "postgresql://user:password@localhost:5432/chirpy?sslmode=disable" status

Example migration file:

-- +goose Up
CREATE TABLE users (
    id UUID PRIMARY KEY,
    created_at TIMESTAMP NOT NULL,
    updated_at TIMESTAMP NOT NULL,
    email TEXT NOT NULL UNIQUE
);

-- +goose Down
DROP TABLE users;

API Endpoints

Authentication

Method	Endpoint	Description
POST	/api/users	Create a new user
POST	/api/login	Login and get tokens
POST	/api/refresh	Refresh access token
POST	/api/revoke	Revoke refresh token

Users

Method	Endpoint	Description
PUT	/api/users	Update user profile

Chirps

Method	Endpoint	Description
POST	/api/chirps	Create a new chirp
GET	/api/chirps	Get all chirps (with optional filtering)
GET	/api/chirps/{chirpID}	Get a specific chirp
DELETE	/api/chirps/{chirpID}	Delete a chirp

Admin

Method	Endpoint	Description
GET	/admin/metrics	View API usage metrics
POST	/admin/reset	Reset the database (dev mode only)

Webhooks

Method	Endpoint	Description
POST	/api/polka/webhooks	Handle subscription events

Installation and Setup

Prerequisites

• Go 1.24 or later
• PostgreSQL
• Environment variables (see below)

Environment Variables

Create a .env file in the project root with the following:

DB_HOST=localhost
DB_PORT=5432
DB_USER=your_user
DB_PASSWORD=your_password
DB_NAME=chirpy
JWT_SECRET=your_jwt_secret

Note

This project was built as part of the Boot.dev backend programming curriculum, designed to provide hands-on experience with building a RESTful API service in Go.