This is a maintenance update to zipkin which has no api impact.
* zipkin-server supports cassandra now
* zipkin-web is now javascript (even if still hosted on a scala process)
This updates to latest zipkin, adding a flag to gzip spans before
posting them. Note this is set to false by default as it requires servers
to also be latest. We can flip the default once we can assume that.
Ex. `spring.zipkin.compression.enabled = true`
This includes updates to the latest zipkin-web image and zipkin-java
dependency.
zipkin-web's notable as it does a lot more in javascript, ex it no
longer does server-side mustache template rendering. It also makes one
less call to the services endpoint when rendering the search page.
zipkin-java's in-memory span store is now in the core jar and also can
render the dependency tree. This means it is now feature-parity with
mysql (but still merely a test span-store). zipkin-java also now tests
that it can run without optional dependencies.
This includes better dependency aggregation than before. For example,
you no longer need mysql to view the dependency graph, as the in-memory
server supports aggregation now. Also, if you log "ca" on a root span,
the associated service will show on the dependency graph on the far
left. This allows you to show uninstrumented clients of note. Similarly,
if you log "sa" on a leaf node, the destination will show on the far
right. You'd use "sa" for uninstrumented services like databases, auth
servers or cloud apis.
Note: 0.5.2 uses spring boot 1.3.2
Zipkin 0.4.1 obviates some duplication of configuration. It is also the
first version that's published as a docker image.
By switching to the published image of zipkin-java, we can be more
consistent, as `spring-cloud-sleuth-zipkin-stream` is derived from that,
not the scala query service.
