[cassandra] YAML configuration template versioning

[yannmh]

[cassandra] YAML configuration template versioning

• Enhance DatadogMonitor resource with a version attribute.
• Use version attribute in cassandra recipe to version, i.e.
  select the appriopriate YAML configuration file.
  Two versions are currently available
  • 1 (Default): Legacy YAML configuration file, compatible with
    Cassandra < 2.2.
  • 2: Required for Cassandra > 2.2, use the YAML configuration file introduced with
    DataDog/dd-agent@2df7566
• Enable cassandra_aliasing option to comply with
  [jmxfetch][cassandra] 0.9.0 + enable CASSANDRA-4009 support  dd-agent#2035

More information:
DataDog/dd-agent#2142

This is quite an important change, would you mind taking a pass on it @remh, @miketheman please ?

Thanks

[miketheman]

@yannmh You can likely run rake style:ruby:auto_correct to handle 90% of the reported style issues.

[yannmh]

Thanks @miketheman. I fixed the offenses 🎨. and updated the PR.

[yannmh]

Brought the last changes discussed @remh. I'll merge it after i get your 👍

[remh]

LGTM, what's the best way to document this ?

[yannmh]

@remh I think the current way to do it is by adding relevant comments in the recipe itself 😏 , c.f. https://github.com/DataDog/chef-datadog/blob/master/recipes/cassandra.rb#L3-L26.
@miketheman could you confirm this point please ?

[yannmh]

Added some documentation.

[remh]

LGTM but @miketheman should give the final 👍

[miketheman]

Thanks! We're planning a merge-a-thon next week.

[miketheman]

Getting back to this now.

@yannmh There seems to be a slight mismatch between the current dd-agent example and the erb template here.

Here's a diff:

       Expected equivalent JSON
       Diff:


       @@ -46,18 +46,13 @@
              {
                "exclude": {
                  "keyspace": [
       -            "OpsCenter",
                    "system",
                    "system_auth",
                    "system_distributed",
       -            "system_schema",
                    "system_traces"
                  ]
                },
                "include": {
       -          "bean_regex": [
       -            ".*keyspace=.*"
       -          ],
                  "domain": "org.apache.cassandra.metrics",
                  "name": [
                    "TotalDiskSpaceUsed",

1. The OpsCenter keyspace appears in dd-agent's example config exclusion - should it be excluded?
2. The system_schema was excluded from dd-agent in [cassandra] exclude new system_schema keyspace dd-agent#2339 - this is not reflected in this pull yet.
3. The bean_regex is from [cassandra] Exclude aggregated metrics not associated with a specific keyspace dd-agent#2271 - should this be applied to the current template, or only to the version 2 template?

Items 1 and 2 were released with Agent 5.7.0, Item 3 is pending Agent 5.7.4 release.

[miketheman]

Pinging @yannmh & @sethrosenblum for follow-up questions in last comment.

[sethrosenblum]

It looks to me like all these things should be carried over to this PR. @johnaxel can you confirm that? question 3 looks like it should only apply to version 2.

[johnaxel]

Agreed on all counts @sethrosenblum.

[sethrosenblum]

@miketheman 🎾

[miketheman]

@sethrosenblum Thanks! I believe this branch needs a rebase against master to pick up the current test suite.

[miketheman]

Thanks @sethrosenblum and @yannmh ! I've added a spec test to cover these templates, and may remove the kitchen tests in the next minor version.