Earthquake API - Example app using kotlin-logging-opentracing-decorator

Example Ktor application instrumented with OpenTracing using ktor-opentracing, using kotlin-logging for logging and kotlin-logging-opentracing-decorator to write logs to spans.

Retrieves data about earthquakes that happened today using an API from the U.S. Geological Survey.

Running

1. Start an all-in-one Jaeger backend with in-memory storage.

    docker run -d --name jaeger \
      -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 \
      -p 5775:5775/udp \
      -p 6831:6831/udp \
      -p 6832:6832/udp \
      -p 5778:5778 \
      -p 16686:16686 \
      -p 14268:14268 \
      -p 14250:14250 \
      -p 9411:9411 \
      jaegertracing/all-in-one:1.20
   

2. Start the application.

    ./gradlew run
   

3. Send some requests. Other routes available are /earthquake/biggest and /earthquake/biggerthan/5 (where 5 is a parameter).

    curl localhost:8080/earthquake/latest
    {
      "location" : "21 km SSE of Karluk, Alaska",
      "magnitude" : 1.9,
      "timeGMT" : "2020-11-02 09:46:39"
    }  
   

4. See traces in Jaeger.

   http://localhost:16686/

5. Stop the Jaeger docker container.

    docker ps
    docker stop <containerId>
   

Steps

1. Import the kotlin-logging-opentracing-decorator dependency. (Commit).

   implementation 'com.github.fstien:kotlin-logging-opentracing-decorator:0.1.0'
   

2. Call the withOpenTracingLogs extension function on your loggers. (Commit).

   val logger = KotlinLogging.logger {}.withOpenTracingLogs()