Integration between Finagle tracing to Zipkin transports including http, kafka and scribe.
Finagle will use a tracer that it detects in the classpath. For example, depending on
io.zipkin.finagle:zipkin-finagle-http_2.12 will send to Zipkin over Http.
You can look at the example for this in use.
Choosing a tracer explicitly
You can also explicitly choose a tracer, which is more reliable, at the tradeoff of more configuration.
Here an example initializing an http client in scala and java
client = Http.client .withTracer(new HttpZipkinTracer()) .withLabel("frontend") // becomes the zipkin service name .newService("remotehost:8080");
client = Http$.MODULE$.client() .withTracer(new HttpZipkinTracer()) .withLabel("frontend") // becomes the zipkin service name .newService("remotehost:8080");
zipkin-finagle configuration is via global flags.
Global flags can either be set by system property, or commandline argument (ex if using TwitterServer).
Ex the following are equivalent ways to trace every request:
$ java -Dzipkin.initialSampleRate=1.0 ... $ java -cp my-twitter-server.jar -zipkin.initialSampleRate=1.0
Here are the flags that apply to all transports:
|zipkin.initialSampleRate||0.001 (0.1%)||Percentage of traces to sample (report to zipkin) in the range [0.0 - 1.0]|
io.zipkin.finagle:zipkin-finagle-http_2.12 to your classpath will configure Finagle to report trace data to a Zipkin server via HTTP.
Here are the flags that apply to Http:
|zipkin.http.host||localhost:9411||The network location of the Zipkin http service. See http://twitter.github.io/finagle/guide/Names.html|
|zipkin.http.hostHeader||zipkin||The Host header used when sending spans to Zipkin|
|zipkin.http.compressionEnabled||true||True implies that spans will be gzipped before transport|
Ex. Here's how to configure the Zipkin server with a system property:
$ java -Dzipkin.http.host=192.168.99.100:9411 ...
io.zipkin.finagle:zipkin-finagle-kafka_2.12 to your classpath will configure Finagle to report trace data to a Kafka topic. The minimum Kafka server version is 0.8.2.2
Here are the flags that apply to Kafka:
|zipkin.kafka.bootstrapServers||localhost:9092||Initial set of kafka servers to connect to, rest of cluster will be discovered (comma separated)|
|zipkin.kafka.topic||zipkin||Kafka topic zipkin traces will be sent to|
Ex. Here's how to configure the Kafka server with a system property:
$ java -Dzipkin.kafka.bootstrapServers=192.168.99.100 ...
io.zipkin.finagle:zipkin-finagle-scribe_2.12 to your classpath will configure Finagle to report trace data to the zipkin category of Scribe.
Here are the flags that apply to Scribe:
|zipkin.scribe.host||localhost:1463||The network location of the Scribe service. See http://twitter.github.io/finagle/guide/Names.html|
Ex. Here's how to configure the Scribe host with a system property. In this case pointing directly to a zipkin server:
$ java -Dzipkin.scribe.host=zipkinhost:9410 ...
You can also configure zipkin tracers programmatically. Here's an example:
HttpZipkinTracer.Config config = HttpZipkinTracer.Config.builder() // The frontend makes a sampling decision (via Trace.letTracerAndId) and propagates it downstream. // This property says sample 100% of traces. .initialSampleRate(1.0f) // All servers need to point to the same zipkin transport .host("127.0.0.1:9411").build(); Tracer tracer = HttpZipkinTracer.create(config, // print stats about zipkin to the console new JavaLoggerStatsReceiver(Logger.getAnonymousLogger()));
The following metrics are reported under a transport-specific category to the configured
StatsReceiver. For example, if using kafka, they are reported relative to "zipkin.kafka".
|spans||the count of spans recorded by the tracer|
|span_bytes||the count of encoded span bytes recorded by the tracer|
|spans_dropped||the count of spans dropped for any reason. For example, failure queueing or sending.|
|messages||the count of messages sent to zipkin. Ex POST requests or Kafka messages.|
|message_bytes||the count of encoded message bytes sent. This includes encoding overhead and excludes compression.|
|messages_dropped/exception_class_name+||count of messages dropped broken down by cause.|
|span_queue_size||last count of spans in the pending queue|
|span_queue_bytes||last count of encoded span bytes in the pending queue|