S1P Sleuth Demo

This repository contains a demo that demonstrates various less known features of Spring Cloud Sleuth.

How to use it

This demo repository is part of a bigger demo system. To get started just initialize the submodules.

$ git submodules init
$ git submodules update

Now you can start the whole system (ELK, 4 demo apps, Zipkin) by running

$ pushd vagrant-elk-box
$ ./getReadyForConference.sh
$ popd vagrant-elk-box

Now, wait for some time for the Vagrant box to start, demo apps to start, Zipkin to start and some requests get sent.

You’re ready to run this application. Just start it and curl

$ curl --header "X-B3-Flags:1" localhost:8765/s1p

or using httpie

$ http localhost:8765/s1p X-B3-Flags:1

What do we show in this app

Dalston

• Creating spans via annotations

  • especially useful for interfaces (e.g. Spring Data)

• Baggage

  • Sleuth specific (via baggage_ header prefix)

• Span adjusters

  • list of custom adjusters of spans before reporting

Edgware

• RestTemplateBuilder support

  • the built RestTemplate is tracing aware

• Zipkin load balanced/discovery using Eureka

  • pass the service id in the URL

• Reactor Support

  • tracing context passed through Flux

• Zipkin2 Support

  • starter-zipkin now points to Zipkin2

• Deprecation of Stream server

  • migrate to Zipkin2 with rabbit

Finchley

• WebFlux & WebClient support

  • tracing context passed through the Flux

  • WebClient is tracing aware

• Removal of Stream server

  • you should use Zipkin 2 native messaging support

  • migrate by having both the old Stream server and the new Zipkin 2 store spans to the same storage

  • start migrating apps from Sleuth Stream client to Zipkin 2

• Removal of OAuth2 support

  • will be removed once it’s re-added in Security

Demo Script

• Create a project from start.spring.io (Reactive Web, Zipkin, Lombok)

• Assuming that the vagrant-elk-box gets updated to Edgware for the samples, need to update zipkin dependency to zipkin2 (assuming that I don’t update initlizr) [Edgware]

• Write a s1p Controller returning Mono<String> [Finchley]

• Create a MyService class that will call service1 via WebClient [Finchley]

• Add the WebClient.Builder bean - explain that RestTemplate / RestTemplateBuilder can be used [Finchley / Edgware]

• Set spring.application.name and spring.sleuth.sampler.percentage=1.0 in properties

• Run the app and see if things pop up in Zipkin

• Set baggage baggage → s1p in controller and run again - show how baggage gets picked in service1 [Dalston]

• Create 2 methods in MyService, one @NewSpan(“surprise”) the other @ContinueSpan(log = “very_important_method”), both with `@SpanTag method params. Methods should sleep and log some stuff out. [Dalston]

• Run again, show new spans. Show the baggage logs, show the annotation logs

• Say that you don’t like the span names. You’d like the span that has http.path to have a changed name. Create a SpanAdjuster Bean that will check http.path tag to contain one with path /s1p and change its name to hacked!. Rerun the application [Dalston]

• Change sampler percentage to 0.0 and show that spans are not sampled. Now call http localhost:8080/s1p X-B3-Flags:1 and show that the debug mode works fine - the span is sampled [Dalston]

• Create a Foo class with Uuid field, change @TagValue to contain a resolver on one of the methods. Create a bean TagValueResolver myCustomTagValueResolver that will return foo’s uuid or any object’s to string [Dalston]

• Show how you could find Zipkin from Service Discovery spring.zipkin.baseUrl: http://zipkinserver/ [Edgware]

• Add the @EnableAsync and @Async method on the MyService. Add the @SpanName on the method and add some logging. Until Edgware the method’s name was the span name - now it has changed [Edgware]

• Calling an external, unmanaged service. In MyService add the callPivotal method. Create a span manually [Dalston] Showing how to call a peer service. Create a RestTemplateBuilder bean [Edgware], that will point to https://pivotal.io. Build the RestTemplate in MyService constructor. New method in MyService with @NewSpan. Add a tag lc ⇒ Pivotal. Set CS before the call try {} finally {} over RestTemplate call. In finally set peer.service to pivotal, peer.ipv4 e.g. InetAddress.getByName("pivotal.io").getHostAddress() `, `"peer.port", "80". Finally log event CR. Re-run and show the new pivotal service [Dalston]