Jaeger Microservices implementation

This project consists of two rudimentary micro-services having separate databases with one using Postgres and other Redis. The aim of this project is to setup, learn Jaeger, and Open Tracing standards in a micro-services environment.

Note: kafka branch has some kafka instrumentation. Please read the [kafka section] in that branch to know more. Also, no_kafka branch has instrumentaion on how to treat postgres as a separate service in Open Tracing.

Note: This project is done only for experimental purposes and should only be used as a reference.

Architecture

Pre-requisites

• Java, 1.8 is the tested version.
• Golang, 1.13 is the tested version.
• Docker (to run Jaeger)

Environment setup instructions

Run Jaeger using docker to capture tracing data using:

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

Start Postgres container used by customer service:

docker run --name postgres -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=admin -p 5432:5432 -d postgres

Start Redis container used by order service:

docker run --name redis -p 6379:6379 -d redis

Running instructions

Run customer service using:

cd customerservice
./mvnw spring-boot:run

Run Order service using:

cd orderservice
go run main.go

Test setup

Open browser or use a curl client to invoke /customer api:

curl localhost:8080/customer/1

Note: Ignore the output of the curl command; It is not relevent to Jaeger and this project.

Navigate to Jaeger from browser: http://localhost:16686/

You should see 4 services in Jaeger including Customer, Order, postgres, and redis. Search traces of Customer service and it should have 5 spans created, and trace data of all four services invoked with the request.

Order service is running on port 9090; You can curl it using:

curl http://localhost:9090/orders?customerID=2

Compare traces

There is a separate API for comparing traces in Jaeger. This API is calling order service 3 times and hence differ in calls to /customer endpoint.

curl localhost:8080/compare/customer/1

Baggage

Name of the logged in user is set as a baggage item in customer service. It travels with all http requests to order service and set as a tag in order span.

Helm Chart

For instructions on how to deploy helm chart for this project please checkout to Helm Setup.