If telemetry is a dependency in your application, and the telemetry is not explicitly disabled, telemetry events will be emitted for AppIdentity.generate_proof/2, AppIdentity.verify_proof/3, and AppIdentity.Plug. See AppIdentity.Telemetry for more information.

Telemetry Events

All of AppIdentity's telemetry events are spans, consisting of :start and :stop events. These are always in the form [:app_identity, <telemetry_type>, <event>].

The events are:

• [:app_identity, :generate_proof, :start] emitted when AppIdentity.generate_proof/2 or AppIdentity.generate_proof!/2 is called.
• [:app_identity, :generate_proof, :stop] emitted when AppIdentity.generate_proof/2 or AppIdentity.generate_proof!/2 finishes, either on success or failure. Telemetry is generated prior to the raising of any exceptions for AppIdentity.generate_proof/2.
• [:app_identity, :plug, :start] emitted when AppIdentity.Plug is called. If AppIdentity.Plug is called in-line, exceptions may be thrown if there are configuration issues and telemetry will not be emitted.
• [:app_identity, :plug, :stop] emitted when the response is sent after AppIdentity.Plug completes.
• [:app_identity, :verify_proof, :start] emitted when AppIdentity.verify_proof/3 or AppIdentity.verify_proof!/3 is called.
• [:app_identity, :verify_proof, :stop] emitted when AppIdentity.verify_proof/3 or AppIdentity.verify_proof!/3 finishes, either on success or failure. Telemetry is verified prior to the raising of any exceptions for AppIdentity.verify_proof/3.

Measurements

All AppIdentity telemetry events measure one of two things:

• :start events always measure monotonic_time (:erlang.monotonic_time/0) and system_time (:erlang.system_time/0).

• :stop events always measure monotonic_time (:erlang.monotonic_time/0) and duration (the difference between the start time and stop time).

Metadata

All AppIdentity telemetry includes a telemetry_span_context key which is a :erlang.reference/0. In this version, this value will be generated with the :start event and reused for the :stop event.

When a measurement type is given as t:telemetry_app, this will be one of the following values:

[:app_identity, :generate_proof, :start] Metadata

• app: telemetry_app/0
• options: a list of AppIdentity.option/0

[:app_identity, :generate_proof, :stop] Metadata

• app: telemetry_app/0
• options: a list of AppIdentity.option/0
• One of:
  • proof: The generated proof string
  • error: A descriptive error

[:app_identity, :plug, :start] Metadata

• conn: Plug.Conn.t/0
• options: A map that may have the following keys (derived from AppIdentity.Plug.Config.param/0):
  • apps: a list of telemetry_app/0 values
  • finder: if present, the string "function (anonymous)" for an anonymous finder function or "function (module.function/1)" for a finder function specified by name.
  • headers: a list of identity header names
  • header_groups: a map of header groups to lists of header names
  • on_failure: the atom value of AppIdentity.Plug.Config.on_failure/0 or if the on_failure configuration is AppIdentity.Plug.Config.on_failure_callback/0, it will be either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • on_success: if present, either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • on_resolution: if present, either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • disallowed: a AppIdentity.disallowed/0 value.

[:app_identity, :plug, :stop] Metadata

• conn: Plug.Conn.t/0, updated after processing
• options: A map with the following keys (derived from AppIdentity.Plug.Config.param/0):
  • apps: a list of telemetry_app/0 values
  • finder: if present, the string "function (anonymous)" for an anonymous finder function or "function (module.function/1)" for a finder function specified by name.
  • headers: a list of identity header names
  • header_groups: a map of header groups to lists of header names
  • on_failure: the atom value of AppIdentity.Plug.Config.on_failure/0 or if the on_failure configuration is AppIdentity.Plug.Config.on_failure_callback/0, it will be either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • on_success: if present, either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • on_resolution: if present, either the string "function (anonymous)" for an anonymous callback or "function (module.function/1)" for a named callback.
  • disallowed: a AppIdentity.disallowed/0 value.

[:app_identity, :verify_proof, :start] Metadata

• app: telemetry_app/0
• options: a list of AppIdentity.option/0
• One of:
  • candidate: The candidate proof string
  • proof: The parsed proof

[:app_identity, :verify_proof, :stop] Metadata

• app: telemetry_app/0. In the case of an error, this will be the same app value as was reported in the :start event. If not, this value will be the post-verification version of the app.
• options: a list of AppIdentity.option/0
• One of:
  • candidate: The candidate proof string
  • proof: The parsed proof
• In case of an error:
  • error: A descriptive error

Disabling Telemetry

Telemetry may be disabled by setting this for your configuration:

config :app_identity, AppIdentity.Telemetry, enabled: false

Recompile app_identity if this setting is changed:

$ mix deps.compile --force app_identity