health-check

Nodejs Health Check API that responds with a JSON object based on the health status of all other backend dependencies.

Descriptions

In this project, we define an express app that listens on port 3005. The app has one endpoint /health with GET method.

The backendDependencies array holds the names and URLs of all the backend dependencies that we want to check for health status.

When a GET request is made to /health, the server iterates over all backend dependencies and makes a GET request to their /health endpoint. If the request is successful, the dependency is marked as "OK" in the healthStatus object, otherwise it is marked as "Error".

After all APIs have been checked, the isHealthy variable is set to true if all APIs are "OK", otherwise it is set to false.

Finally, the server responds with a JSON object containing the isHealthy flag and an array of results for each backend API.

This API allows for GET query requests and responds with a JSON object based on the health status of all backend dependencies. It can be used to quickly check the status of all backend dependencies and take appropriate action if any of them are not functioning correctly.

Aurora DB Health Check

The dbConfig object holds the configuration information for our Aurora DB.

When a GET request is made to /db/health, the server attempts to create a connection to the Aurora DB using the mysql2/promise library. If the connection is successful, the server runs a simple SELECT 1 query to check the health of the database. If the query is successful, the server returns a JSON object with a status of "OK", otherwise it returns a JSON object with a status of "Error".

Run in local

git clone https://github.com/jayantapaul-18/health-check.git
cd health-check
npm install
node index.js
or,
npm install -g nodemon
nodemon index.js

Running pre-commit checks

pre-commit installs git hooks configured in .pre-commit-config.yaml

Install pre-commit and commitizen to use

brew install commitizen
brew install pre-commit

pre-commit install
pre-commit install --hook-type commit-msg
pre-commit run --all-files

git add .
git status
pre-commit run --all-files
cz c
git commit -m 'feat: health check api with backend api status response'
git push origin main --force

Release - standard-version

Run the below command to create a new release CHANGELOGS

npm install --save-dev standard-version
npm install --save-dev commitizen
npx commitizen init cz-conventional-changelog --save-dev --save-exact
# Install commitlint cli and conventional config
npm install --save-dev @commitlint/config-conventional @commitlint/cli
# Install Husky - Husky improves commits and more
npm install husky --save-dev
# Activate hooks
npx husky install
# Add hook
npx husky add .husky/commit-msg 'npx --no-install commitlint --edit "$1"'
# run
npm run commit
npm run release
git push --follow-tags origin main && npm publish

To Bypass hooks`

We can bypass pre-commit and commit-msg hooks using Git -n/--no-verify option:

git commit -m "my no commit" --no-verify

Request & Response

curl --location 'http://localhost:3005/health?tls=0'
curl --location 'http://localhost:3005/health?tls=1'

Response

{
  "isHealthy": true,
  "node_tls_reject_unauthorize": "0",
  "timeStamp": "2023-05-20T23:58:46.262Z",
  "healthStatus": [
    {
      "i": "✅",
      "name": "API 1",
      "status": "OK",
      "uptime": 49
    },
    {
      "i": "✅",
      "name": "API 2",
      "status": "OK",
      "uptime": 20
    },
    {
      "i": "✅",
      "name": "Backend-Node",
      "status": "OK",
      "uptime": 475
    }
  ]
}

Using Docker

❯ docker build -t health-check .
- Need to optimize - TO DO

Code Structure

tree -L 1

├── CHANGELOG.md
├── CODEOWNERS
├── Dockerfile
├── LICENSE
├── README.md
├── REQUEST.http
├── app.log
├── commitlint.config.js
├── config.js
├── index.js
├── node_modules
├── package-lock.json
├── package.json
├── prepare.js
└── swagger.json

LICENSE