Simplified Datadog Java APM Example

A very simple Java application using Datadog APM w/ the Datadog dd-trace-api as described in the Datadog Java APM docs.

This repo leverages Docker for ease of use.

Noteworthy

This small project is for demonstration purposes only.
It does not make use any container orchestrator.
It's original intent was to be used on a developer's local machine.
It is not production grade.

Prerequisites

Install Java OpenJDK for your platform
Install Docker for your platform

Send APM Metrics to Datadog

Run the Datadog Dockerized Agent

Run to build the image: docker build -t dd-agent ./agent/

Run the following, replacing {your_api_key_here} with your own DD API key.

docker run -d --rm --name dd-agent \
  -v /var/run/docker.sock:/var/run/docker.sock:ro \
  -v /proc/:/host/proc/:ro \
  -v /sys/fs/cgroup/:/host/sys/fs/cgroup:ro \
  -e API_KEY={your_api_key_here} \
  -e DD_APM_ENABLED=true \
  -p 8126:8126/tcp \
  -e SD_BACKEND=docker \
  -e LOG_LEVEL=DEBUG \
  -e DD_LOGS_STDOUT=yes \
  -e DD_PROCESS_AGENT_ENABLED=true \
  dd-agent

Run the Java example

Run ./gradlew build (or gradlew.bat if on windows)

Set an environment variable with the DD docker agent IP:

  DD_AGENT_IP_ADDR=`docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' dd-agent`

Run to build the docker image: docker build -t dd-java-apm --build-arg DD_AGENT_IP=$DD_AGENT_IP_ADDR .

Run to start the container:

docker run -d -p 8081:8080 --rm --name dd-java-apm dd-java-apm \
-e TAGS=host:dd-java-apm-demo-openjdk,env:demo

Additional Docker commands

Run to see the containers running: docker ps
Run to see container logs: docker logs dd-java-apm
Run to get to bash prompt for the container: docker exec -it dd-java-apm /bin/bash
Run to stop the container: docker stop dd-java-apm
Run to remove the container: docker rm dd-java-apm

See APM in Datadog

Hit these web urls locally to generate some APM metrics and traces:
- http://localhost:8081
- http://localhost:8081/sleepy
  - Noteworthy
    - As an unauthenticated GitHub request, you may see:
      { "message": "API rate limit exceeded for 76.97.244.208. (But here's the good news: Authenticated requests get a higher rate limit. Check out the documentation for more details.)", "documentation_url": "https://developer.github.com/v3/#rate-limiting" }
      Pretty quickly when executing /lookup -- this will result in a 500 from this application since it isn't doing any proper exception handling
Visit Datadog APM env:demo and the dd-java-apm-example-openjdk service should be listed.
- The "home" (e.g. http://localhost:8081/) request mapping should result in a flame graph that looks like:

ckelner / datadog-java-apm-example