🎓 Student CRUD REST API

Golang + Gin + PostgreSQL + Prometheus + Makefile

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🧭 Overview

A production-grade, versioned RESTful API for managing student records. Built with Go and the Gin web framework, backed by a PostgreSQL database. Designed with clean architecture, environment configuration, and monitoring readiness.

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📌 Key Features

• ✅ CRUD operations on student records
• 🔐 Environment-based configuration via .env
• 🧪 Unit tests for different endpoints
• 📊 Prometheus-compatible /metrics endpoint
• 🔁 Healthcheck endpoint /healthcheck
• 🔧 Makefile automation (build, run, test, migrate)
• 📬 Postman collection for API testing

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📖 What the API Does

The API supports:

• Create a new student
• Read all students or a specific student by ID
• Update existing student details
• Delete a student record

Additional endpoints:

• /healthcheck — Readiness status
• /metrics — Prometheus-compatible metrics for observability

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🗂️ Project Structure

One2N-SRE-Bootcamp/
│
├── .github/                      # GitHub-specific files
│   └── workflows/
│       └── cicd.yaml             # GitHub Actions CI/CD pipeline
│
├── argocd/                       # ArgoCD configuration
│   └── argocd-app.yml            # ArgoCD application manifest
│
├── helm/                         # Helm chart directory
│   ├── templates/
│   │   ├── application.yml       # Kubernetes Deployment
│   │   ├── database.yml          # Kubernetes DB Deployment
│   │   ├── postgres-pv.yml       # PersistentVolume for PostgreSQL
│   │   └── postgres-secret.yml   # Secrets for PostgreSQL
│   ├── Chart.yaml                # Helm chart definition
│   └── values.yaml               # Default values for the Helm chart
├── routes.go                     # Registers routes and middleware with Gin engine
├── schema.sql                    # SQL schema to create 'students' table
├── scripts/                      # Utility scripts
│   └── devtools.sh               # Tools installation script
├── prometheus.go                 # Prometheus metrics middleware & endpoint
├── student-data/                 # Directory to store student-related data
├── model.go                      # Defines Student struct 
├── .dockerignore                 # Exclude unnecessary files 
├── .env                          # Environment variables (excluded from version control)
├── .gitignore                    # Git ignore file
├── config.go                     # App configuration
├── db.go                         # Connects to PostgreSQL using environment config
├── docker-compose.yaml           # Docker Compose config for local setup
├── Dockerfile                    # Dockerfile for building the application image
├── go.mod / go.sum               # Go module files for dependency tracking
├── handler.go                    # Implements all HTTP handlers with logging
├── handler_test.go               # Unit tests using sqlmock for isolated handler testing
├── main.go                       # Application entry point
├── makefile                      # Makefile automation targets
└── migrate.go                    # Migration logic

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🚀 Getting Started

1. 📦 Prerequisites

• Go installed
• PostgreSQL installed and running locally
• psql CLI access

2. 🛠️ Setup PostgreSQL

Create a database and user:

CREATE USER studentuser WITH PASSWORD 'yourpassword';
CREATE DATABASE studentdb OWNER studentuser;
GRANT ALL PRIVILEGES ON DATABASE studentdb TO studentuser;

3. 🔐 Create .env file

Populate the .env (example below):

DB_HOST=localhost
DB_PORT=5432
DB_USER=studentuser
DB_PASSWORD=yourpassword
DB_NAME=studentdb
DB_SSLMODE=disable
PORT=8080

4. 🔁 Migrate database schema

Use Makefile or run manually:

make migrate

OR

psql -h localhost -U studentuser -d studentdb -f schema.sql

5. ▶️ Build and run the server

Use:

make run

OR

go run .

6. 🧪 Test the API

• Use the included postman_collection.json imported into Postman.

• Or use curl commands for endpoints such as:

  # Health check
  curl http://localhost:8080/healthcheck
  

  # ➕ Add a student
  curl -X POST http://localhost:8080/api/v1/students \
    -H "Content-Type: application/json" \
    -d '{"name":"Alice","age":22,"email":"alice@example.com"}'
  

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🧪 Testing

• Run tests locally:

make test

OR

go test -v

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🐳 Containerise REST API

Instructions to build the image and run the docker container

# Building the Docker image:
make docker-build
OR
docker build -t yourdockerusername/student-api:tag .

# Running the Docker image:
make docker-run
OR
docker run --env-file .env -p 8080:8080 yourdockerusername/student-api:tag

# Tagging the docker image:
docker tag student-api:tag yourdockerusername/student-api:tag

# Pushing the docker image:
make docker-push
OR
docker push yourdockerusername/student-api:tag

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📦📦 Setup one-click local development setup

# Pre-requisite for existing tools that must already be installed (Only for Linux)

cd scripts && chmod +x devtools.sh
./devtools.sh

# Run docker compose
make docker-compose
OR
docker-compose up # Run DB + API using docker-compose

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☸️ Deploy REST API & its dependent services in K8s

# Note: The commands can change according to the file structure

cd templates

kubectl create namespace student-api (Create a namespace for k8s isolation)

kubectl apply -f postgres-secret.yml -f postgres-pv.yml -f database.yml -f application.yml -n student-api

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📈 Deploy REST API & its dependent services using Helm Charts