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rubygraphite

How to use regular expression in fetching data from graphite?

I want to fetch data from different counters from graphite in one single request like:-

summarize(site.testing_server_2.triggers_unknown.count,'1hour','sum')&format=json

summarize(site.testing_server_2.requests_failed.count,'1hour','sum')&format=json

summarize(site.testing_server_2.core_network_bad_soap.count,'1hour','sum')&format=json

and so on.. 20 more.

But I don't want to fetch 

summarize(site.testing_server_2.module_xyz_abc.count,'1hour','sum')&format=json

in that request how can i do that?

This is what I tried:

summarize(site.testing_server_2.*.count,'1hour','sum')&format=json&from=-24hour

It gets json data for 'module_xyz_abc' too, but that i don't want.

Solution

  • You can't use regular expressions per se, but you can use some similar (in concept and somewhat in format) matching techniques available within the Graphite Render URL API. There are a few ways you can "match" within a target's "bucket" (i.e. between the dots).

    Target Matching

    Asterisk * match

    The asterisk can be used to match ANY -zero or more- character(s). It can be used to replace the entire bucket (site.*.test) or within the bucket (site.w*t.test). Here is an example:

    site.testing_server_2.requests_*.count

    This would match site.testing_server_2.requests_failed.count, site.testing_server_2.requests_success.count, site.testing_server_2.requests_blah123.count, and so forth.

    Character range [a-z0-9] match

    The character range match is used to match on a single character (site.w[0-9]t.test) in the target's bucket and is specified as a range or list. For example:

    site.testing_server_[0-4].requests_failed.count

    This would match on site.testing_server_0.requests_failed.count, site.testing_server_1.requests_failed.count, site.testing_server_2.requests_failed.count, and so forth.

    Value list (group capture) {blah, test, ...} match

    The value list match can be used to match anything in the list of values, in the specified portion of the target's bucket.

    site.testing_server_2.{triggers_unknown,requests_failed,core_network_bad_soap}.count

    This would match site.testing_server_2.triggers_unknown.count, site.testing_server_2.requests_failed.count, and site.testing_server_2.core_network_bad_soap.count. But nothing else, so site.testing_server_2.module_xyz_abc.count would not match.

    Answer

    Without knowing all of your bucket values it is difficult to be surgical with the approach (perhaps with a combination of the matching options), so I'll recommend just going with a value list match. This should allow you to get all of the values in one -somewhat long- request. For example (and keep in mind you'd need to include all of your values):

    summarize(site.testing_server_2.{triggers_unknown,requests_failed,core_network_bad_soap}.count,'1hour','sum')&format=json&from=-24hour

    For more, see Graphite Paths and Wildcards