mackerel-plugin-json

README

mackerel-plugin-json

Json custom metrics plugin for mackerel.io agent.

Synopsis

mackerel-plugin-json -url=<url to get JSON> [-prefix=<prefix for a metric name>] [-insecure] [-include=<expression>] [-exclude=<expression>]

• -url always needs to be specified.
• If you want to skip a SSL certificate validation (e.g. using a self-signed certificate), you need to specify -insecure.
• If you want to get only metrics that matches a regular expression, specify the expression with -include. If you want to get only ones that doesn't match an expression, use -exclude.
• Metrics that have non-number value (string, null, etc.) are omitted.
• Arrays are supported. Metrics' name will contain a serial number like custom.elements.0.xxx, custom.elements.1.xxx and so on.

Example of mackerel-agent.conf

[plugin.metrics.jolokia]
command = mackerel-plugin-json -url='http://127.0.0.1:8778/jolokia/read/java.lang:type=Memory' -include='HeapMemoryUsage' -prefix='custom.jolokia'

Examples of output from the plugin

Given the following JSON:

curl -s http://127.0.0.1:8778/jolokia/read/java.lang:type=Memory | jq .
{
  "request": {
    "mbean": "java.lang:type=Memory",
    "type": "read"
  },
  "value": {
    "ObjectPendingFinalizationCount": 0,
    "Verbose": false,
    "HeapMemoryUsage": {
      "init": 1073741824,
      "committed": 1069023232,
      "max": 1069023232,
      "used": 994632048
    },
    "NonHeapMemoryUsage": {
      "init": 2555904,
      "committed": 44040192,
      "max": 1350565888,
      "used": 43070016
    },
    "ObjectName": {
      "objectName": "java.lang:type=Memory"
    }
  },
  "timestamp": 1455079714,
  "status": 200
}

The output should be:

# Option : -url='http://127.0.0.1:8778/jolokia/read/java.lang:type=Memory'

custom.value.HeapMemoryUsage.used       994632048.000000        1503586907
custom.value.HeapMemoryUsage.init       1073741824.000000       1503586907
custom.value.HeapMemoryUsage.max        1069023232.000000       1503586907
custom.timestamp        1455079714.000000       1503586907
custom.status   200.000000      1503586907
custom.value.NonHeapMemoryUsage.committed       44040192.000000 1503586907
custom.value.NonHeapMemoryUsage.max     1350565888.000000       1503586907
custom.value.NonHeapMemoryUsage.used    43070016.000000 1503586907
custom.value.NonHeapMemoryUsage.init    2555904.000000  1503586907
custom.value.HeapMemoryUsage.committed  1069023232.000000       1503586907

# Option : -url='http://127.0.0.1:8778/jolokia/read/java.lang:type=Memory' -include='\.HeapMemoryUsage'

custom.value.HeapMemoryUsage.init       1073741824.000000       1503587081
custom.value.HeapMemoryUsage.committed  1069023232.000000       1503587081
custom.value.HeapMemoryUsage.max        1069023232.000000       1503587081
custom.value.HeapMemoryUsage.used       994632048.000000        1503587081

# Option : -url='http://127.0.0.1:8778/jolokia/read/java.lang:type=Memory' -exclude='(timestamp|status)'

custom.value.HeapMemoryUsage.init       1073741824.000000       1503587166
custom.value.HeapMemoryUsage.committed  1069023232.000000       1503587166
custom.value.HeapMemoryUsage.max        1069023232.000000       1503587166
custom.value.HeapMemoryUsage.used       994632048.000000        1503587166
custom.value.NonHeapMemoryUsage.max     1350565888.000000       1503587166
custom.value.NonHeapMemoryUsage.used    43070016.000000 1503587166
custom.value.NonHeapMemoryUsage.init    2555904.000000  1503587166
custom.value.NonHeapMemoryUsage.committed       44040192.000000 1503587166

You can also get metrics from any APIs that returns a JSON. For example:

# Option : -url='https://[your-github-token]@api.github.com/repos/doublemarket/private-repo' -include='(_count|watchers|issues)' -prefix='custom.github.some-private-repo'

custom.github.private-repo.open_issues_count    1171.000000     1503587879
custom.github.private-repo.open_issues  1171.000000     1503587879
custom.github.private-repo.network_count        15042.000000    1503587879
custom.github.private-repo.forks_count  15042.000000    1503587879
custom.github.private-repo.stargazers_count     36733.000000    1503587879
custom.github.private-repo.subscribers_count    2444.000000     1503587879
custom.github.private-repo.watchers_count       36733.000000    1503587879
custom.github.private-repo.watchers     36733.000000    1503587879