Equals condition does not support Booleans

[alkuzad]

As continuation of forum topic: https://discuss.elastic.co/t/drop-event-when-up-is-false/92046

Equals filter does not support Booleans - it makes using Hearbeat < 6.0 harder as user has to check for same conditions as provided in check instead of simply checking up status for filtering.

Reproduce:

1. Save configuration

heartbeat.monitors:
- type: http
  schedule: '@every 2m'
  urls: ["http://service.example.com"]
  check.response.status: 200
heartbeat.scheduler:
  limit: 25
output.logstash:
  hosts: ["logstash.example.com:5044"]
processors:
 - drop_event:
     when:
      equals: 
       up: true

2. Run configuration ./heartbeat -path.config $PWD -c heartbeat.test.yml -v -e
3. Output:

2017/07/10 08:25:07.635778 beat.go:285: INFO Home path: [/home/sweet/home/heartbeat-5.5.0-linux-x86_64] Config path: [/home/sweet/home/heartbeat-5.5.0-linux-x86_64] Data path: [/home/sweet/home/heartbeat-5.5.0-linux-x86_64/data] Logs path: [/home/sweet/home/heartbeat-5.5.0-linux-x86_64/logs]
2017/07/10 08:25:07.635807 beat.go:186: INFO Setup Beat: heartbeat; Version: 5.5.0
2017/07/10 08:25:07.635855 condition.go:455: ERR Failed to initialize lookup condition: unknown type bool passed to extractString
2017/07/10 08:25:07.635867 beat.go:339: CRIT Exiting: error initializing processors: unknown type bool passed to extractString
Exiting: error initializing processors: unknown type bool passed to extractString

Heartbeat version: 5.4.3, 5.5.0

[ewgRa]

Possible fixed in PR #5954, and #5659 is describe same problem as here.

[ruflin]

Closing this as #5954 was merged.