hotrod

README

Hot R.O.D. - Rides on Demand

This is a demo application that consists of several microservices and illustrates the use of the OpenTracing API. It can be run standalone, but requires Jaeger backend to view the traces. A tutorial / walkthough is available:

• as a blog post Take OpenTracing for a HotROD ride,
• as a video OpenShift Commons Briefing: Distributed Tracing with Jaeger & Prometheus on Kubernetes.

Features

• Discover architecture of the whole system via data-driven dependency diagram
• View request timeline & errors, understand how the app works
• Find sources of latency, lack of concurrency
• Highly contextualized logging
• Use baggage propagation to
  • Diagnose inter-request contention (queueing)
  • Attribute time spent in a service
• Use open source libraries with OpenTracing integration to get vendor-neutral instrumentation for free

Running

Run everything via docker-compose

• Download docker-compose.yml from https://github.com/jaegertracing/jaeger/blob/master/examples/hotrod/docker-compose.yml
• Run Jaeger backend and HotROD demo with docker-compose -f path-to-yml-file up
• Access Jaeger UI at http://localhost:16686 and HotROD app at http://localhost:8080
• Shutdown / cleanup with docker-compose -f path-to-yml-file down

Alternatively, you can run each component separately as described below.

Run Jaeger backend

An all-in-one Jaeger backend is packaged as a Docker container with in-memory storage.

docker run \
  --rm \
  --name jaeger \
  -p6831:6831/udp \
  -p16686:16686 \
  jaegertracing/all-in-one:latest

Jaeger UI can be accessed at http://localhost:16686.

Run HotROD from source

go get github.com/jaegertracing/jaeger
cd $GOPATH/src/github.com/jaegertracing/jaeger
make install
cd examples/hotrod
go run ./main.go all

Run HotROD from docker

docker run \
  --rm \
  --link jaeger \
  --env JAEGER_AGENT_HOST=jaeger \
  --env JAEGER_AGENT_PORT=6831 \
  -p8080-8083:8080-8083 \
  jaegertracing/example-hotrod:latest \
  all

Then open http://127.0.0.1:8080