Support multiple sample events

[jsoriano]

Add a new samples setting to the system test configuration files, that can be optionally used to select specific documents for the collected sample files.

For example, to select a document that contains the 200 status code:

samples:
  - name: "200"
    condition:
      key: "http.response.status_code"
      value: "200"

When these samples are defined, the default sample_event.json is not collected. Instead, one document is collected for each defined sample, called sample_event_<name>.json, where <name> is the name in the config.

When multiple events are collected, all of them are rendered in the README when event is used.

A change is required in package-spec to support the multiple sample files.

Closes #773

[elasticmachine]

💚 Build Succeeded

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• Commit: baabdc8

History

• 💚 Build #1419 succeeded 313bec7
• 💚 Build #1412 succeeded 0575b81
• 💔 Build #1411 failed 14d25c0
• 💔 Build #1409 failed 739c861
• 💔 Build #1408 failed 5bf1579

cc @jsoriano