This listener adds OpenTracing instrumentation at Flogo engine level and tracers implementations (Zipkin over HTTP or Kafka, Jaeger) to send traces generated by flows and activities to corresponding collectors.
For an introduction of concepts, read the OpenTracing documentation.
Minimum required version of Flogo: 0.5.7
This listener is not available yet with the Flogo Web UI.
The listener must be installed once for an application. Basically it's just a matter of adding the right package import in the imports.go file. This is performed seamlessly with the Flogo CLI.
In the directory of a Flogo project (with a flogo.json file), run:
flogo install github.com/square-it/flogo-opentracing-listenerFinally, build the application:
flogo build -eThe binary is ready to be run in ./bin directory.
To use this listener once it is installed, no modification of source code is required. Instead, it is only required to define an application-level configuration and to run a collector.
Currently, all flows of an application have the same OpenTracing configuration set using environment variables.
For instance, to enable collection of traces by a Zipkin collector over HTTP transport:
export FLOGO_OPENTRACING_IMPLEMENTATION=zipkin
export FLOGO_OPENTRACING_TRANSPORT=http
export FLOGO_OPENTRACING_ENDPOINTS=http://127.0.0.1:9411/api/v1/spansReplace 127.0.0.1 by the actual IP of the Zipkin collector.
| Environment variable | Possible values | Description |
|---|---|---|
| FLOGO_OPENTRACING_IMPLEMENTATION | zipkin, jaeger | Choose which implementation of OpenTracing tracer to use. Zipkin and Jaeger are available |
| FLOGO_OPENTRACING_TRANSPORT | http, kafka(for zipkin only) | http is supported by both Zipkin and Jaeger kafka is only supported by Zipkin |
| FLOGO_OPENTRACING_ENDPOINTS | http://127.0.0.1:9411/api/v1/spans (zipkin over HTTP) 10.1.0.1:29092,10.1.0.2:29092,10.1.0.3:29092 (zipkin over Kafka) |
A comma-separated list of endpoints |
This listener can send traces to the following collectors:
For test purposes, here are quick methods to get collectors up and running locally, using Docker.
To start a single-node instance of a Zipkin server with HTTP transport, run:
docker run --name zipkin -d -p 9411:9411 openzipkin/zipkinFor Kafka transport, start a single-node instance of a Kafka server with its Zookeeper:
mkdir -p /tmp/kafka
cd /tmp/kafka
curl -fsSL https://raw.githubusercontent.com/confluentinc/cp-docker-images/5.0.0-post/examples/kafka-single-node/docker-compose.yml -o docker-compose.yml
# uncomment if using Docker Machine
# sed -i "s|localhost:|$(docker-machine ip $(docker-machine active)):|" docker-compose.yml
docker-compose up -dThen start a single-node instance of a Zipkin server with Kafka transport by running:
docker run --name zipkin -d -p 9411:9411 -e KAFKA_BOOTSTRAP_SERVERS=127.0.0.1:29092 openzipkin/zipkinIf using Docker Machine, run instead:
docker run --name zipkin -d -p 9411:9411 -e KAFKA_BOOTSTRAP_SERVERS=$(docker-machine ip $(docker-machine active)):29092 openzipkin/zipkinTo start a single-node instance of a Jaeger server with HTTP transport, run:
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 9411:9411 \
jaegertracing/all-in-one