fluent-plugin-kubernetes_metadata_filter, a plugin for Fluentd

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Installation

gem install fluent-plugin-

Configuration

Configuration options for fluent.conf are:

  • kubernetes_url - URL to the API server. This is required
  • apiVersion - API version to use (default: v1beta3)
  • ca_file - path to CA file for Kubernetes server certificate validation
  • verify_ssl - validate SSL certificates (default: true)
  • client_cert - path to a client cert file to authenticate to the API server
  • client_key - path to a client key file to authenticate to the API server
  • bearer_token_file - path to a file containing the bearer token to use for authentication
  • container_name_to_kubernetes_name_regexp - the regular expression used to extract kubernetes metadata (pod name, container name, namespace) from the Docker container name. This must used named capture groups for pod_container_name, pod_name & namespace (default: '\/?[^_]+_(?<pod_container_name>[^\.]+)[^_]+_(?<pod_name>[^_]+)_(?<namespace>[^_]+)')
  • cache_size - size of the cache of Kubernetes metadata to reduce requests to the API server (default: 1000)
  • cache_ttl - TTL in seconds of each cached element. Set to negative value to disable TTL eviction (default: 3600 - 1 hour)
<source>
  type tail
  path /var/lib/docker/containers/*/*-json.log
  pos_file fluentd-docker.pos
  time_format %Y-%m-%dT%H:%M:%S
  tag docker.*
  format json
  read_from_head true
</source>

<filter docker.var.lib.docker.containers.*.*.log>
  type docker_metadata
</filter>

<filter docker.var.lib.docker.containers.*.*.log>
  type kubernetes_metadata
  kubernetes_url https://localhost:8443
</filter>

<match **>
  type stdout
</match>

Example input/output

Docker logs in JSON format. Log files are normally in /var/lib/docker/containers/*/*-json.log, depending on what your Docker data directory is.

Assuming following inputs are coming from a log file: df14e0d5ae4c07284fa636d739c8fc2e6b52bc344658de7d3f08c36a2e804115-json.log:

{
  "log": "2015/05/05 19:54:41 \n",
  "stream": "stderr",
  "time": "2015-05-05T19:54:41.240447294Z"
}

Then output becomes as belows

{
  "log": "2015/05/05 19:54:41 \n",
  "stream": "stderr",
  "docker": {
    "id": "df14e0d5ae4c07284fa636d739c8fc2e6b52bc344658de7d3f08c36a2e804115",
    "name": "/k8s_fabric8-console-container.efbd6e64_fabric8-console-controller-9knhj_default_8ae2f621-f360-11e4-8d12-54ee7527188d_7ec9aa3e",
    "container_hostname": "fabric8-console-controller-9knhj",
    "image": "fabric8/hawtio-kubernetes:latest",
    "image_id": "b2bd1a24a68356b2f30128e6e28e672c1ef92df0d9ec01ec0c7faea5d77d2303",
    "labels": {}
  }
  "kubernetes": {
    "host": "jimmi-redhat.localnet",
    "pod_name":"fabric8-console-controller-98rqc",
    "container_name": "fabric8-console-container",
    "namespace": "default",
    "uid": "c76927af-f563-11e4-b32d-54ee7527188d",
    "labels": {
      "component": "fabric8Console"
    }
  }
}

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

Copyright (c) 2015 jimmidyson