- name: server
  type: group
  description: >
    Contains envoy proxy server stats
  fields:
    - name: cluster_manager
      type: group
      fields:
        - name: active_clusters 
          type: integer
          description: >
            Number of currently active (warmed) clusters
        - name: cluster_added
          type: integer
          description: >
            Total clusters added (either via static config or CDS)
        - name: cluster_modified
          type: integer
          description: >
            Total clusters modified (via CDS)
        - name: cluster_removed
          type: integer
          description: >
            Total clusters removed (via CDS)
        - name: warming_clusters
          type: integer
          description: >
            Number of currently warming (not active) clusters

    - name: filesystem
      type: group
      fields:
        - name: flushed_by_timer
          type: integer
          description: >
            Total number of times internal flush buffers are written to a file due to flush timeout
        - name: reopen_failed
          type: integer
          description: >
            Total number of times a file was failed to be opened
        - name: write_buffered
          type: integer
          description: >
            Total number of times file data is moved to Envoys internal flush buffer
        - name: write_completed
          type: integer
          description: >
            Total number of times a file was written
        - name: write_total_buffered 
          type: integer
          description: >
            Current total size of internal flush buffer in bytes

    - name: runtime
      type: group
      fields:
        - name: load_error
          type: integer
          description: >
            Total number of load attempts that resulted in an error
        - name: load_success
          type: integer
          description: >
            Total number of load attempts that were successful
        - name: num_keys 
          type: integer
          description: >
            Number of keys currently loaded
        - name: override_dir_exists
          type: integer
          description: >
            Total number of loads that did use an override directory
        - name: override_dir_not_exists
          type: integer
          description: >
            Total number of loads that did not use an override directory
        - name: admin_overrides_active
          type: integer

    - name: listener_manager
      type: group
      fields:
        - name: listener_added
          type: integer
          description: >
            Total listeners added (either via static config or LDS)
        - name: listener_create_failure
          type: integer
          description: >
            Total failed listener object additions to workers
        - name: listener_create_success
          type: integer
          description: >
            Total listener objects successfully added to workers
        - name: listener_modified
          type: integer
          description: >
            Total listeners modified (via LDS)
        - name: listener_removed
          type: integer
          description: >
            Total listeners removed (via LDS)
        - name: total_listeners_active
          type: integer
          description: >
            Number of currently active listeners
        - name: total_listeners_draining
          type: integer
          description: >
            Number of currently draining listeners
        - name: total_listeners_warming
          type: integer
          description: >
            Number of currently warming listeners

    - name: stats
      type: group
      fields:
        - name: overflow
          type: integer
          description: >
            Total number of times Envoy cannot allocate a statistic due to a shortage of shared memory

    - name: server
      type: group
      fields:      
        - name: days_until_first_cert_expiring
          type: integer
          description: >
            Number of days until the next certificate being managed will expire
        - name: live
          type: integer
          description: >
            1 if the server is not currently draining, 0 otherwise
        - name: memory_allocated
          type: integer
          description: >
            Current amount of allocated memory in bytes
        - name: memory_heap_size
          type: integer
          description: >
            Current reserved heap size in bytes
        - name: parent_connections
          type: integer
          description: >
            Total connections of the old Envoy process on hot restart
        - name: total_connections
          type: integer
          description: >
            Total connections of both new and old Envoy processes
        - name: uptime
          type: integer
          description: >
            Current server uptime in seconds
        - name: version
          type: integer
          description: >
            Integer represented version number based on SCM revision
        - name: watchdog_mega_miss
          type: integer
        - name: watchdog_miss
          type: integer
        - name: hot_restart_epoch
          type: integer
          description: >
            Current hot restart epoch

    - name: http2
      type: group
      fields:
        - name: header_overflow
          type: integer
          description: >
            Total number of connections reset due to the headers being larger than Envoy::Http::Http2::ConnectionImpl::StreamImpl::MAX_HEADER_SIZE (63k)
        - name: headers_cb_no_stream
          type: integer
          description: >
            Total number of errors where a header callback is called without an associated stream. This tracks an unexpected occurrence due to an as yet undiagnosed bug
        - name: rx_messaging_error
          type: integer
          description: >
            Total number of invalid received frames that violated section 8 of the HTTP/2 spec. This will result in a tx_reset
        - name: rx_reset
          type: integer
          description: >
            Total number of reset stream frames received by Envoy
        - name: too_many_header_frames
          type: integer
          description: >
            Total number of times an HTTP2 connection is reset due to receiving too many headers frames. Envoy currently supports proxying at most one header frame for 100-Continue one non-100 response code header frame and one frame with trailers
        - name: trailers
          type: integer
          description: >
            Total number of trailers seen on requests coming from downstream
        - name: tx_reset
          type: integer
          description: >
            Total number of reset stream frames transmitted by Envoy