Allow customize localEndpoint.serviceName

[carnei-ro]

I have a lot of kong clusters. The plugin (version 1.2.0) has the localEndpoint.serviceName hard-coded as "kong", making it difficult to understand which "kong cluster" handled the request.
So far, I forked and coded the plugin to let me customize the tag lc (component). I think the serviceName would be better tho.

[kikito]

Custom tags can be added via the static_tags config option. Example declarative config:

plugins:
  name: zipkin
  ...
  static_tags:
    - name: kong-instance-name
      value: kong-production-1

Will add a tag called kong-instance-name with value kong-production-1 to all the request tags.

It is not possible to use this feature in order to override the default tags (such as lc, which will always have the value kong), but you should be able to filter traces using a different tag.

I hope this compromise is acceptable.

[carnei-ro]

Nice, I can use static_tags;
I know the issue is not about it, but, have you considering also adding the tag with requested host and protocol? We have the http.path, I think http.host and http.protocol (e.g. HTTP/1.1) would be nice too.

[kikito]

have you considering also adding the tag with requested host and protocol? We have the http.path, I think http.host and http.protocol (e.g. HTTP/1.1) would be nice too.

I haven't considered adding those - it was not suggested by the Zipkin team when I took over this plugin. If you think that addition is worth it, please open a separate issue for those to keep things organized (even better if you are able to provide that functionality in the form of a PR).

[carnei-ro]

Thanks I'll do

[carnei-ro]

#111 @kikito