apm-toy-app

A simple app to trace.

Prerequisites

1. Install docker and docker-compose (you can try sudo pip install docker-compose)
2. (Optional) Install go and its dependency management tool
3. You need a Datadog account. If you don't have one, just use the free trial.

Get the app running

1. Get your Datadog API key (Integrations > APIs in the app) and paste it here

Note: each time you'll change your API key, you'll need to rebuild the datadog-agent docker image.

1. Get your Datadog API key (Integrations > APIs) and paste it here
2. Run the app

docker-compose up

This command should launch a minimal golang server along with redis, postgres and the datadog-agent.

3. Go to http://localhost:8080/, you should get something like that:

(247 hits) - City: Utrecht, 234323 inhabitants

Each time you hit this URL, the golang server will return a different city and its population from postgres and will also tell you how many times you hit this endpoint.

Check the datadog-agent status

1. Connect to the container running the datadog-agent

docker exec -it apmtoyapp_datadog_1 bash

2. Run the info command of the agent

service datadog-agent info

3. Check that postgres and redis are properly reporting metrics

 Checks
  ======

    postgres (5.16.0)
    -----------------
      - instance #0 [OK]
      - Collected 15 metrics, 0 events & 1 service check

    redisdb (5.16.0)
    ----------------
      - instance #0 [OK]
      - Collected 36 metrics, 0 events & 1 service check
      - Dependencies:
          - redis: 2.10.5

4. Go in the Datadog app, Metrics > Explorer and check you can see your metrics in the app.

Possible issues

• If you encounter some dependency issues, try to run dep ensure (make sure you have dep installed).

• If you want to make modifications to the datadog image, you have to manually rebuild it with docker build --no-cache datadog -t apmtoyapp_datadog.