GitHub user st2654 opened a pull request:
https://github.com/apache/camel/pull/2448
CAMEL-12656: Fixed root span id for multiple routes.
https://issues.apache.org/jira/browse/CAMEL-12656
I have added screenshots in Jira already.
Camel-Zipkin does not report traces with root span id when there are
multiple routes.
For example:
`from("direct:foo")
.delay(1000)
.to("direct:bar")
.to("direct:moo")
.to("direct:tar");
from("direct:bar")
.delay(2000);
from("direct:moo")
.delay(1000);
from("direct:tar")
.delay(3000);`
Root SpanId(TraceId) should be for service-name = direct:foo and the trace
in UI should show all the 4 routes in one sequence. But it breaks. Check the
attached screenshot: Traces Breaking.png
I looked into the code and figured out why its happening. Here is the code
which is breaking the functionality.
Class Name: ZipkinTracer.ZipkinRoutePolicy
Inside onExchangeBegin() method
// add on completion after the route is done, but before the consumer
writes the response
// this allows us to track the zipkin event before returning the response
which is the right time
exchange.addOnCompletion(new SynchronizationAdapter() {
@Override
public void onAfterRoute(Route route, Exchange exchange) {
String serviceName = getServiceName(exchange, route.getEndpoint(),
true, false);
Brave brave = getBrave(serviceName);
if (brave != null) {
serverResponse(brave, serviceName, exchange);
}
}
@Override
public String toString() {
return "ZipkinTracerOnCompletion[" + routeId + "]";
}
});
Using onAfterRoute() : if the exchange is being routed through multiple
routes, there will be callbacks for each route.
I have fix for it:
If I use onExchangeDone() instead of above code. The traces are reported
properly. Check screenshots.
https://zipkin.io/pages/instrumenting.html
Note This process must be repeated if the service makes multiple downstream
calls. That is each subsequent span will have the same trace id and parent id,
but a new and different span id.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/st2654/camel CAMEL-12656
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/camel/pull/2448.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #2448
----
commit ca7fdaecc6645506a81c24409602ba3819b169b5
Author: Sourabh Taletiya <st2654@...>
Date: 2018-08-01T03:49:24Z
CAMEL-12656: Fixed root span id for multiple routes.
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