Configuration

Configuration Options

The Ruby agent can be configured via the config/scout_apm.yml Yaml file and/or environment variables. A config file with your organization key is available for download as part of the install instructions.

Heroku users should use environment variables instead of the scout_apm.yml.

ERB evaluation

ERB is evaluated when loading the config file. For example, you can set the app name based on the hostname:

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

Environment Variables

You can also configure Scout APM via environment variables. Environment variables override settings provided in scout_apm.yml. To configure Scout via enviroment variables, uppercase the config key and prefix it with SCOUT_. For example, to set the key via environment variables: export SCOUT_KEY=YOURKEY

Common Configurations

The following configuration settings are available:

Setting Name	Description	Default	Required
name	Name of the application (ex: ‘Photos App’).	`Rails.application.class.to_s. sub(/::Application$/, '')`	Yes
key	The organization API key.		Yes
monitor	Whether monitoring should be enabled.	`false`	Yes
errors_enabled	Whether Error Monitoring should be enabled.	`false`	No
auto_instruments	Instrument custom code with Auto Instruments.	`false`	No
log_level	The logging level of the agent.	`INFO`	No

Additional Configurations

Setting Name	Description	Default	Required
dev_trace	Indicates if DevTrace, the Scout development profiler, should be enabled. Note this setting only applies to the development environment.	`false`	No
detailed_middleware	When true, the time spent in each middleware is visible in transaction traces vs. an aggregrate across all middlewares. This adds additional overhead and is disabled by default as middleware is an uncommon bottleneck.	`false`	No
hostname	Allows renaming of the node/host name	`Socket.gethostname`	No
revision_sha	The Git SHA that corresponds to the version of the app being deployed.	See docs	No
scm_subdirectory	The relative path from the base of your Git repo to the directory which contains your application code.		No
ignore	An Array of web endpoints that Scout should not instrument. Routes that match the prefixed path (ex: `['/health', '/status']`) will be ignored by the agent.	`[]`	No
enable_background_jobs	Indicates if background jobs should be monitored.	`true`	No
collect_remote_ip	Automatically capture end user IP addresses as part of each trace’s context.	`true`	No
record_queue_time	Automatically capture request queue time when a queuing request header is found.	`true`	No
auto_instruments_ignore	Excludes the listed files names from being auto instrumented. Ex: `['application_controller']`.	`[]`	No
errors_ignored_exceptions	Excludes certain exceptions from being reported	`[ActiveRecord::RecordNotFound, ActionController::RoutingError]`	No
errors_filtered_params	Filtered parameters in exceptions	`[password, s3-key]`	No
log_file_path	The path to the `scout_apm.log` log file directory. Use `stdout` to log to STDOUT.	`Environment#root+log/` or `STDOUT` if running on Heroku.	No
proxy	Specify the proxy URL (ex: `https://proxy`) if a proxy is required.		No
host	The protocol + domain where the agent should report.	`https://scoutapm.com`	No
uri_reporting	By default Scout reports the URL and filtered query parameters with transaction traces. Sensitive parameters in the URL will be redacted. To exclude query params entirely, use `path`.	`filtered_params`	No
disabled_instruments	An Array of instruments that Scout should not install. Each Array element should should be a string-ified, case-sensitive class name (ex: `['Elasticsearch','HttpClient']`). The default installed instruments can be viewed in the agent source.	`[]`	No
timeline_traces	Send traces in both the summary and timeline formats.	`true`	No

Environments

It typically makes sense to treat each environment (production, staging, etc) as a separate application within Scout and ignore the development and test environments. Configure a unique app name for each environment as Scout aggregates data by the app name.

Ex:

export SCOUT_KEY=YOURKEY
export SCOUT_NAME=YOURAPPNAME (Production)