Fix compatibility with newer versions of Graphite

[jwatroba]

Pull Request Checklist

Fixes: https://github.com/sensu-plugins/sensu-plugins-graphite/issues/63

Before:

{"command":"handler-graphite-event.rb","type":"pipe","filters":[],"severities":["ok","critical"],"handle_flapping":false,"handle_silenced":false,"name":"graphite_event"},"output":["{\"what\":\"sensu_event\",\"tags\":\"tag1,tag2,tag3\",\"data\":\"ok\",\"when\":{timestamp}}\n"]}

After (with --tags-as-array): {"command":"handler-graphite-event.rb --tags-as-array","type":"pipe","filters":[],"severities":["ok","critical"],"handle_flapping":false,"handle_silenced":false,"name":"graphite_event"},"output":["{\"what\":\"sensu_event\",\"tags\":[\"tag1,tag2,tag3\"],\"data\":\"ok\",\"when\":{timestamp}}\n"]}

After (without --tags-as array) -- No change from original behavior: {"command":"handler-graphite-event.rb","type":"pipe","filters":[],"severities":["ok","critical"],"handle_flapping":false,"handle_silenced":false,"name":"graphite_event"},"output":["{\"what\":\"sensu_event\",\"tags\":\"tag1,tag2,tag3\",\"data\":\"ok\",\"when\":{timestamp}}\n"]}

General

• [x] Update Changelog following the conventions laid out on Keep A Changelog

• [ ] Update README with any necessary configuration snippets

• [ ] Binstubs are created if needed

• [x] RuboCop passes

• [x] Existing tests pass

New Plugins

• [ ] Tests

• [ ] Add the plugin to the README

• [ ] Does it have a complete header as outlined here

Purpose

Known Compatablity Issues

[majormoses]

Thanks for your contribution to Sensu plugins! Without people like you submitting PRs we couldn't run the project. I will review it shortly.

[majormoses]

@jwatroba does this break backwards compatibility on older graphite versions?

[jwatroba]

Actually, might not be. According to the release notes on 1.0 of Graphite:

The events API now requires tags to be an array when creating tagged events. Previous versions only accepted string attributes. Tags are also serialized as arrays.

Might need a switch depending on the users version. Sorry, I originally thought it was backwards compatible.

[majormoses]

Yup, looks like we need to detect the version of graphite and conditionally make it an array. I have added the label as a reminder until we find a solution for backwards compatibility.

[majormoses]

@jwatroba I have not really seen a good way of detecting graphite version remotely what do you think about making it an argument? We could default for now on the old one to prevent breaking anyone and allow those that need it to move forward and later on we can change the default to the newer tag methods.

[jwatroba]

@majormoses I updated the pull request to default to the legacy version of Graphite and added '-l' to switch to 'latest' compatibility. I've tested in on post 1.0 Graphite and it works.

[majormoses]

Hmm I don't know that we want to have an argument that implies it will always work with latest what about naming it something like --tags-as-arrays? This is more descriptive and at some point we can change the default to true, and eventually remove the extra code.

[majormoses]

Can you please also add a changelog entry per our guidelines and a testing artifact?

[majormoses]

Also looks like there is an extra newline if you can kill that it will appease the rubocop.

[jwatroba]

Ok, I've updated the handler to use --tags-as-array or -t, updated the Changelog and added some before/after log entries to the pull request.

[majormoses]

released: https://rubygems.org/gems/sensu-plugins-graphite/versions/3.1.0