Log Metadata object with job, process, and host information

Changes

• Add kojo_metadata object to logging structure that contains job, process and host keys.
• In the kojo_metadata.host object there is:
  • host_name: Contains the gethostname() results. On docker this is just a hash of the container ID, but on EC2 or Kubernetes it will be a more verbose string.
  • load_average: the instantaneous Load average that is also sampled by canEnvironmentSustainAdditionProcesses()
• In the kojo_metadata.process object you can find memory stats for the process that executing your Kōjō job.
  • memory_usage_bytes: current memory allocated to the PHP process via emalloc()
  • memory_peak_usage_bytes: peak memory allocated
  • memory_limit_bytes: The results of ini_get('memory_limit') string like '128M' normalized into bytes.

Example output

Example dashboard: https://snapshot.raintank.io/dashboard/snapshot/C9KwxOAe2rugM73YIDikDUyN7ezmoz9d?orgId=2

{
    "time": "Thu, 19 Sep 19 13:38:44.508414 UTC",
    "level": "notice",
    "message": "Got lucky this time boss!",
    "context": {
        "event_type": "task_status",
        "top_level_status": "success",
        "nested_object": {
            "random_letters": "bright",
            "random_word": "materialization",
            "random_value": 25,
            "status": "success"
        }
    },
    "context_json_last_error": 0,
    "kojo_metadata": {
        "job": {
            "kojo_job_id": 8268,
            "type_code": "complex_logging_structure",
            "name": "Protean DLCP Example",
            "priority": 7,
            "importance": 10,
            "work_at_date_time": "2019-09-19 13:38:27",
            "next_state_request": "none",
            "assigned_state": "working",
            "previous_state": "crashed",
            "worker_uri": "Neighborhoods\\KojoFitnessUseCase46\\V1\\Worker\\Facade",
            "worker_method": "start",
            "can_work_in_parallel": true,
            "last_transition_date_time": "2019-09-19 13:38:43",
            "last_transition_micro_time": "1568900323188672",
            "times_worked": 4,
            "times_retried": 0,
            "times_held": 0,
            "times_crashed": 3,
            "times_panicked": 0,
            "created_at_date_time": "2019-09-19 13:38:27",
            "completed_at_date_time": null,
            "delete_after_date_time": null
        },
        "process": {
            "process_id": 7750,
            "parent_process_id": 7240,
            "path": "\/server[7236]\/root[7240]\/job[7750]",
            "uuid": "af35fa582d5b-172.21.0.7-\/server[7236]\/root[7240]\/job[7750]-1568900322.717618-2585409713",
            "type_code": "job",
            "memory_usage_bytes": 10681168,
            "memory_peak_usage_bytes": 10722400,
            "memory_limit_bytes": 134217728
        },
        "host": {
            "host_name": "af35fa582d5b",
            "load_average": 4.83
        }
    }
}