Ruby Configuration

How do I configure Scout APM for Ruby?

Scout can be configured via: - A config/scout_apm.yml YAML file - Environment variables (which override yaml settings)

For Heroku, use environment variables. For other deployments, either approach works.

What are the required configuration settings?

How do I configure Scout using environment variables?

Uppercase the config key and prefix with SCOUT_. For example:

export SCOUT_KEY=your_key_here
export SCOUT_NAME="My Application"
export SCOUT_MONITOR=true

Can I use ERB in the config file?

Yes. ERB is evaluated when loading the config file. For example:

common: &defaults
  name: <%= "ProjectPlanner.io (#{Rails.env})" %>

How do I configure different environments separately?

Set unique app names per environment to keep data separate:

common: &defaults
  name: <%= "YOUR_APP_NAME (#{Rails.env})" %>
  key: YOUR_KEY
  monitor: true

production:
  <<: *defaults

development:
  <<: *defaults
  monitor: false

staging:
  <<: *defaults

Or use environment variables: SCOUT_NAME="My App (Staging)"

How do I ignore certain endpoints?

Use the ignore configuration option to exclude endpoints by path prefix:

ignore: ['/health', '/status']

How do I disable Scout on a specific server?

Set monitor: false in the configuration for that server. You can also use ERB to programmatically enable/disable based on hostname:

monitor: <%= Socket.gethostname.match(/web[1..5]/) %>

What are the logging options?

• log_level: Set to debug, info, warn, or error. Default is INFO.
• log_file_path: Directory for scout_apm.log. Use stdout for STDOUT logging. Heroku defaults to STDOUT.

What is the detailed_middleware option?

By default, Scout aggregates all middleware timings into a single “Middleware” category. Setting detailed_middleware: true shows time spent in each individual middleware. This adds overhead and is disabled by default since middleware is rarely a bottleneck.