Example project for actuatorjs in express

You can find a simple express API with an actuator instantiated in the index.ts file.

Actuator

HealthChecks

This shows how to use both SimpleHealthIndicator and how to extend AbstractHealthIndicator for a simple postgres health check.

Try running docker compose up -d --build express-actuatorjs-app to run the backend without a running database. Then try to curl or open your browser on http://localhost:3000/actuator/health You should get:

{"status":"DOWN","components":{"abstract-postgres":{"status":"DOWN","details":{"error":"connect ECONNREFUSED ::1:5432; connect ECONNREFUSED 127.0.0.1:5432"}},"simple-postgres":{"status":"DOWN","details":{"error":"connect ECONNREFUSED ::1:5432; connect ECONNREFUSED 127.0.0.1:5432"}}}}

Then try it after running docker compose up -d, and check the url again, you should get:

{"status":"UP","components":{"simple-postgres":{"status":"UP"},"abstract-postgres":{"status":"UP"}}}

InfoCheck

A json file is generated upon running bunx generate-info. This will create a file under your outDir if specified in your package.json, or in dist by default. The file is named actuato.info.json.

The .git repository is read to generate it. Make sure to include it in the Containerfile you use to build your image or the git information will be null.

In the example Containerfile, this script is run inside the build script, and the package.json isn't necessary in the last image as dist is the default dir checked for the actuator info file. If you have a different outDir, please keep the package.json file in your final image step.

Once the app is running, check http://localhost:3000/actuator/info to see information on your os, process, git and build from your package.json file.

You should see something like this:

{
  "git": {
    "branch": "main",
    "commit": {
      "id": "1867031",
      "time": "2025-07-09T23:44:57+02:00"
    }
  },
  "build": {
    "name": "express-actuatorjs-app",
    "version": "0.0.1"
  },
  "os": {
    "name": "Linux",
    "version": "5.15.167.4-microsoft-standard-WSL2",
    "arch": "x64"
  },
  "process": {
    "pid": 1,
    "memory": {
      "heapTotal": 4344832,
      "heapUsed": 4516782,
      "rss": 69554176
    },
    "cpus": 4
  }
}