Heroku

Heroku apps send data to Squasher over OpenTelemetry. Fir apps can use a Heroku telemetry drain, and Cedar apps set the OpenTelemetry variables as config vars. Cedar apps can also forward stdout and router logs with a classic log drain. See Log drain.

Prerequisites

The Heroku CLI, signed in, with access to the app.
An ingest key. See Create an ingest key.

Set up the telemetry

Fir apps
Cedar apps

Add a telemetry drain that sends to the Squasher OTLP endpoint:

heroku telemetry:add https://ingest.squasher.ai \
  --app <your-app> \
  --signals traces,metrics,logs \
  --transport http \
  --headers '{"x-squasher-key":"<your ingest key>"}'

Run heroku telemetry --app <your-app> to see the drain.

Set the OpenTelemetry variables as config vars, then add an OpenTelemetry SDK to the app:

heroku config:set -a <your-app> \
  OTEL_EXPORTER_OTLP_ENDPOINT=https://ingest.squasher.ai \
  OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf \
  OTEL_EXPORTER_OTLP_HEADERS="x-squasher-key=<your ingest key>" \
  OTEL_SERVICE_NAME=<your-app> \
  OTEL_RESOURCE_ATTRIBUTES=deployment.environment.name=production

See OpenTelemetry for each language, or use the Node.js SDK.

Log drain

A classic log drain sends every stdout, stderr, and router line as Heroku syslog frames (application/logplex-1). Heroku lines have no environment, so set one in the URL:

heroku drains:add \
  "https://ingest.squasher.ai/v1/drain/heroku/<project-id>?key=<your ingest key>&environment=production" \
  --app <your-app>

Squasher reads the level from the syslog severity or from the message (level=error, router at=error, a leading ERROR, or a stack trace), and stores Heroku error codes such as H12 and R14 as error.type. Lines at error level or above create issues.

What Squasher keeps

Signal	What Squasher stores	What creates an issue
Traces	Spans with attributes, events, and links	Spans with `ERROR` status
Logs	Log records with their attributes	Records at `ERROR` severity or above
Metrics	Gauges, sums, and histograms	Nothing

See What Squasher does with each signal.

Verify

Record one span with ERROR status, or log one line at error severity through OpenTelemetry.
In Squasher, select Issues in the sidebar. The error is at the top of the list.

Limits

With a telemetry drain, Heroku router errors, such as H12, reach Squasher only if Heroku includes them in the telemetry that it sends. A log drain sends router lines.
Plain stdout lines from a Cedar app reach Squasher only through a log drain, an OpenTelemetry logs exporter, or an SDK.

Get started

Guides

Prerequisites

Set up the telemetry

Log drain

What Squasher keeps

Verify

Limits

Next steps

OpenTelemetry

Node.js SDK

​Prerequisites

​Set up the telemetry

​Log drain

​What Squasher keeps

​Verify

​Limits

​Next steps

OpenTelemetry

Node.js SDK

Prerequisites

Set up the telemetry

Log drain

What Squasher keeps

Verify

Limits

Next steps