This does two things: ensures samples don't use Zipkin v1 in any way,
and misaligns the version numbers of zipkin v1 and zipkin v2 apis.
This is an attempt to walk around the gradle plugin issue, which only
exists when someone is using both versions of zipkin.
See https://github.com/spring-projects/spring-boot/issues/10778
with this change the child span of the HTTP filter span gets changed into a span coming from the Controller aspect. The name of the span becomes the name of the method.
- Changed Random instantiation to a shared Random
- Changed the name of the converter
- Changed generator into random
- Span id is now non-nullable.
- it gets generated in the http filter if it's not there
- it's generated in the spring-integration channels if it wasn't set
It's not really necessary to use rabbit, but the existing tests
weren't really using the stream components at all because
zipkin spans were being collected by spring-cloud-sleuth-zipkin.
Recent versions of zipkin and brave operate with http instead of scribe.
This changes the implementation accordingly, as well adds a sampler to
the POST endpoint.
A notable impact is that we no longer require a collector process, as
the zipkin server's POST endpoint is a collector.
