These are the docs for an older version of OPA. Latest stable release is v0.46.1
Monitoring Edit

OpenTelemetry

When run as a server and configured accordingly, OPA will emit spans to an OpenTelemetry collector via gRPC.

Each REST API request sent to the server will start a span. If processing the request involves policy evaluation, and that in turn uses http.send, those HTTP clients will emit descendant spans.

Furthermore, spans exported for policy evaluation requests will contain an attribute opa.decision_id of the evaluation’s decision ID if the server has decision logging enabled.

See the configuration documentation for all OpenTelemetry-related configurables.

Prometheus

OPA exposes an HTTP endpoint that can be used to collect performance metrics for all API calls. The Prometheus endpoint is enabled by default when you run OPA as a server.

You can enable metric collection from OPA with the following prometheus.yml config:

global:
  scrape_interval: 15s
scrape_configs:
  - job_name: "opa"
    metrics_path: "/metrics"
    static_configs:
    - targets:
      - "localhost:8181"

The Prometheus endpoint exports Go runtime metrics as well as HTTP request latency metrics for all handlers (e.g., v1/data).

Metric name Metric type Description Status
go_gc_duration_seconds summary A summary of the GC invocation durations. STABLE
go_goroutines gauge Number of goroutines that currently exist. STABLE
go_info gauge Information about the Go environment. STABLE
go_memstats_alloc_bytes gauge Number of bytes allocated and still in use. STABLE
go_memstats_alloc_bytes_total counter Total number of bytes allocated, even if freed. STABLE
go_memstats_buck_hash_sys_bytes gauge Number of bytes used by the profiling bucket hash table. STABLE
go_memstats_frees_total counter Total number of frees. STABLE
go_memstats_gc_cpu_fraction gauge The fraction of this program’s available CPU time used by the GC since the program started. STABLE
go_memstats_gc_sys_bytes gauge Number of bytes used for garbage collection system metadata. STABLE
go_memstats_heap_alloc_bytes gauge Number of heap bytes allocated and still in use. STABLE
go_memstats_heap_idle_bytes gauge Number of heap bytes waiting to be used. STABLE
go_memstats_heap_inuse_bytes gauge Number of heap bytes that are in use. STABLE
go_memstats_heap_objects gauge Number of allocated objects. STABLE
go_memstats_heap_released_bytes gauge Number of heap bytes released to OS. STABLE
go_memstats_heap_sys_bytes gauge Number of heap bytes obtained from system. STABLE
go_memstats_last_gc_time_seconds gauge Number of seconds since 1970 of last garbage collection. STABLE
go_memstats_lookups_total counter Total number of pointer lookups. STABLE
go_memstats_mallocs_total counter Total number of mallocs. STABLE
go_memstats_mcache_inuse_bytes gauge Number of bytes in use by mcache structures. STABLE
go_memstats_mcache_sys_bytes gauge Number of bytes used for mcache structures obtained from system. STABLE
go_memstats_mspan_inuse_bytes gauge Number of bytes in use by mspan structures. STABLE
go_memstats_mspan_sys_bytes gauge Number of bytes used for mspan structures obtained from system. STABLE
go_memstats_next_gc_bytes gauge Number of heap bytes when next garbage collection will take place. STABLE
go_memstats_other_sys_bytes gauge Number of bytes used for other system allocations. STABLE
go_memstats_stack_inuse_bytes gauge Number of bytes in use by the stack allocator. STABLE
go_memstats_stack_sys_bytes gauge Number of bytes obtained from system for stack allocator. STABLE
go_memstats_sys_bytes gauge Number of bytes obtained from system. STABLE
go_threads gauge Number of OS threads created. STABLE
http_request_duration_seconds histogram A histogram of duration for requests. STABLE

Status Metrics

When Prometheus is enabled in the status plugin (see Configuration), the OPA instance’s Prometheus endpoint also exposes these metrics:

Metric name Metric type Description Status
plugin_status_gauge gauge Number of plugins by name and status. EXPERIMENTAL
bundle_loaded_counter counter Number of bundles loaded with success. EXPERIMENTAL
bundle_failed_load_counter counter Number of bundles that failed to load. EXPERIMENTAL
last_bundle_request gauge Last bundle request in UNIX nanoseconds. EXPERIMENTAL
last_success_bundle_activation gauge Last successfully bundle activation in UNIX nanoseconds. EXPERIMENTAL
last_success_bundle_download gauge Last successfully bundle download in UNIX nanoseconds. EXPERIMENTAL
last_success_bundle_request gauge Last successfully bundle request in UNIX nanoseconds. EXPERIMENTAL
bundle_loading_duration_ns histogram A histogram of duration for bundle loading. EXPERIMENTAL

Health Checks

OPA exposes a /health API endpoint that can be used to perform health checks. See Health API for details.

Status API

OPA provides a plugin which can push status to a remote service. See Status API for details.