Elixir Phoenix telemetry integration

Test the integration

Send and verify events with Elixir Phoenix telemetry integration

Use Elixir Phoenix telemetry integration where your app knows the final result. Collect only the fields you need, then verify a test event before building charts.

1
Choose the outcome
Phoenix API reliability
2
Define the contract
route_template, method, status_code, status, duration_ms, and release
3
Log the final result
Attach once at startup and handle the Phoenix endpoint or router-dispatch stop event. Convert duration units with System.convert_time_unit/3.
4
Check the stored event
Exercise a known fixture, then inspect your_event_table for one correctly typed terminal row.

Before you start

Phoenix endpoint telemetry enabled and a supervised application process that installs handlers once
A server-side HTTP client with bounded connect and response timeouts
A route-template, status, and controlled error taxonomy that excludes request parameters and connection contents

Delivery setup

Install and initialize server-side

Use a supervised client process with a server-side key, bounded HTTP timeouts, and explicit retry limits. Keep ingestion credentials out of browser bundles, client-visible environment variables, source control, logs, and exception messages.

1Create one reusable server-side client. Set its timeout and retry limit.
2Log an event when the operation succeeds, fails, retries, or times out.
3Send test events with known results and inspect the stored rows before enabling an alert.

Snippet

Start with one structured event

Add this shape where the workflow completes, fails, or retries. Then build the dashboard from real fields.

elixir-phoenix

Elixir Phoenix telemetry integration event

elixir

defmodule MyAppWeb.TelemetryOutcome do
  def attach do
    :telemetry.attach(
      "telemetry-phoenix-request-outcome",
      [:phoenix, :endpoint, :stop],
      &__MODULE__.handle_stop/4,
      nil
    )
  end

  def handle_stop(_event, measurements, metadata, _config) do
    conn = metadata.conn

    event = %{
      route_template: conn.private[:phoenix_route] || "unmatched",
      method: conn.method,
      status_code: conn.status,
      status: if(conn.status < 500, do: "success", else: "failed"),
      duration_ms:
        System.convert_time_unit(measurements.duration, :native, :millisecond),
      release: System.get_env("APP_RELEASE", "development")
    }

    # Supervise this app-owned client and give it bounded HTTP timeouts.
    MyApp.TelemetryIngest.enqueue("phoenix_request_completed", event)
  end
end

Event schema

route_template, method, status_code, status, duration_ms, and release

request_id, account_id, environment, node_role, and controlled error_type when approved

No conn.params, query string, request or response body, session, authorization header, stack trace, or unrestricted metadata

Check your setup

Checkpoint 1

Attach once at startup and handle the Phoenix endpoint or router-dispatch stop event. Convert duration units with System.convert_time_unit/3.

Checkpoint 2

Phoenix and Plug stop events do not describe a complete distributed span. Plug may not emit a stop event after an error. Keep exception and trace tools to investigate those failures.

Checkpoint 3

Send events asynchronously through a supervised queue with a size limit. Telemetry HTTP latency should not delay the user request or exhaust the application mailbox.

Verification

Prove the event arrived

Run this after exercising known success and failure cases. Replace the fallback table name if your final event contract differs from the snippet.

elixir-phoenix-verification

Elixir Phoenix telemetry integration verification query

sql

SELECT *
FROM your_event_table
ORDER BY timestamp_utc DESC
LIMIT 20;

Confirm one terminal row per logical outcome, with the expected status, identifiers, units, and UTC time.

Inspect the inferred schema and verify that retries do not change field types or generate a new logical event ID.

Search the stored fields for credentials, raw payloads, prompts, private content, and unbounded error messages.

Exercise a provider timeout, ingestion rejection, and process shutdown before treating the dashboard as complete.

Implementation references

Review the event contract, data-safety guidance, and upstream primary documentation before enabling a new production path.

Application telemetry guide API reliability monitoring API latency SQL Phoenix telemetry events Plug.Telemetry lifecycle boundary

Where to log

Keep the outcome event small and recoverable

This pattern provides

Record the outcome as an event you can query with SQL.
Stable fields for dashboards, alerts, and cross-event correlation.
Test events for checking success, failure, retries, and timeouts.

This pattern does not provide

An OTLP exporter, automatic collection pipeline, or replacement for detailed traces and diagnostic logs.
Exactly-once delivery merely because the payload contains an event ID.
Permission to collect raw provider payloads, user content, credentials, or regulated data.

Delivery and idempotency Batching and shutdown Troubleshoot ingestion

Example event schemas

Check what each event records, when to send it, and which field types it needs. Review the example payload and privacy checklist before using it in production.

API reliability10 fields