ERDDAP Metrics
==============

While ERDDAP provides several methods for obtaining information on its status, none are easily integrated into a
metrics tool like Prometheus. ERDDAPUtil therefore provides a scraper that runs every few minutes to parse the
status.html page and generate Prometheus-style metrics from it. In addition, ERDDAPUtil extends this with its own
metrics (e.g. number of log files removed, failed dataset XML files, etc). These are exposed by the ERDDAPUtil
web service at ``http://localhost:9173/metrics``.

Metrics Exposed
---------------

.. csv-table:: Metrics Exposed
   :header: "Metric Name","Type","Description"

   erddap_last_major_load_seconds,Gauge,Time the last major load took to run (in seconds)
   erddap_datasets_grid,Gauge,Number of gridded ERDDAP datasets
   erddap_datasets_table,Gauge,Number of tabular ERDDAP datasets
   erddap_datasets_load_failed,Gauge,Number of datasets that failed to load
   erddap_datasets_orphaned,Gauge,Number of orphaned datasets
   erddap_users_unique,Gauge,Number of unique ERDDAP users
   erddap_task_thread_runs,Counter,Number of times TaskThread has run
   erddap_touch_thread_runs,Counter,Number of times TouchThread has run
   erddap_os_cpu_load_ratio,Gauge,Total CPU Load [0-1]
   erddap_os_process_cpu_load_ratio,Gauge,ERDDAP Process CPU Load [0-1]
   erddap_os_total_memory_bytes,Gauge,Total memory
   erddap_os_free_memory_bytes,Gauge,Free memory
   erddap_os_total_swap_space_bytes,Gauge,Total swap space
   erddap_os_free_swap_space_bytes,Gauge,Free swap space
   erddap_http_requests_active,Gauge,Number of currently active requests
   erddap_memory_used_bytes,Gauge,Memory actively being used by ERDDAP
   erddap_memory_highwater_bytes,Gauge,High-water mark of memory used by ERDDAP
   erddap_memory_max_bytes,Gauge,Maximum memory available to ERDDAP
   erddap_major_loads,Counter,Total number of major loads by ERDDAP
   erddap_major_load_seconds,Summary,Time the major load took
   erddap_major_load_datasets_tried,Summary,Number of datasets that were attempted to load by a major load process
   erddap_major_load_datasets_failed,Summary,Number of datasets that failed to load by a major load process
   erddap_major_load_datasets_seen,Summary,Total number of datasets seen during the major load
   erddap_http_requests,Counter,Total number of HTTP requests to ERDDAP
   erddap_http_requests_median_succeeded_seconds,Summary,Median success request execution time since last major load
   erddap_http_requests_median_failed_seconds,Summary,Median failed request execution time since last major load
   erddap_all_threads,Gauge,Number of threads currently active
   erddap_major_load_memory_in_use_bytes,Summary,Memory used during the major load
   erddap_gc_calls,Counter,Number of garbage collection calls since the last major load
   erddap_open_files_ratio,Summary,Number of open files
   erddap_requests_by_language_LANGUAGE,Counter,Number of requests for the given language
   erddap_sgtmap_topography_tiles_generated,Counter,Number of topographies generated by SgtMap
   erddap_gshhs_shoreline_tiles_generated,Counter,Number of shorelines generated
   erddap_gshhs_shoreline_cache_used,Gauge,Usage of the shoreline cache
   erddap_gshhs_shoreline_cache_size,Gauge,Max size of the cache
   erddap_sgtmap_national_boundary_tiles_generated,Counter,Number of national boundary tiles generated
   erddap_sgtmap_national_boundary_shoreline_cache_used,Gauge,Usage of the national boundary cache
   erddap_sgtmap_national_boundary_shoreline_cache_size,Gauge,Max size of the cache
   erddap_sgtmap_state_boundary_tiles_generated,Counter,Number of state boundary tiles generated
   erddap_sgtmap_state_boundary_cache_used,Gauge,Usage of the state boundary cache
   erddap_sgtmap_state_boundary_cache_size,Gauge,Max size of the cache
   erddap_sgtmap_river_tiles_generated,Counter,Number of river tiles generated
   erddap_sgtmap_river_cache_used,Gauge,Usage of the river cache
   erddap_sgtmap_river_cache_size,Gauge,Max size of the cache
   erddap_string_interning_canon_map_length,Gauge,
   erddap_string_interning_canon_map_total,Gauge,
   erddap_string_interning_canon_str_holder_map_length,Gauge,
   erddap_string_interning_canon_str_holder_map_total,Gauge,
   erddap_active_threads,Gauge,Number of active threads
   erddap_tomcat_requests,Counter,Number of requests grouped by request type and dataset
   erddap_tomcat_request_bytes,Summary,Total bytes served by tomcat grouped by request type and dataset
   erddap_tomcat_request_processing_time,Summary,Total time taken to serve the request
   erddap_logman_runs,Summary,Number of times log management ran and how long the run took
   erddap_logman_log_files_removed,Counter,Number of files the log management ran


Looking Forward
---------------
In the future, ERDDAPUtil aims to expand metric collection by also parsing the daily email reports and possibly the
ERDDAP logs.