How to filter Request with ddtrace on Rails?

Many Web Application are use monitoring Apps like datadog, CloudWatch, Mackerel and so on. When using a monitoring application, there may be cases where you want to exclude specific HTTP requests from being monitored. So I try to describe how to filter Request with ddtrace on Rails in this article.

Environments

Rails 6.1.4
Ruby 2.7.6
ddtrace 1.4.1

Implement

You need Edit config/initializers/datadog.rb.

Datadog::Pipeline.before_flush(
  Datadog::Pipeline::SpanFilter.new { |span| span.resource =~ /HogeController/ },
)

For example, If You want to remove Healthcheck API…

Datadog::Pipeline.before_flush(
  Datadog::Pipeline::SpanFilter.new { |span| span.resource =~ /HealthcheckController/ },
)

Several Request Filtering

If you want to remove Several Request, You edit this

Datadog::Pipeline.before_flush(
  Datadog::Pipeline::SpanFilter.new { |span| span.resource =~ /HealthcheckController|PingController/ },
)

Check this code in Regular expressions.

# If match return 0
"HealthcheckController" =~ /HealthcheckController|PingController/
=> 0

# If not match return nil
"HealthcheckController" =~ /PingController/
=> nil

"HealthcheckController" =~ /HealthcheckController/
=> 0

Referenced Articles

Thank you for writing!

その辺にいるWebエンジニアの備忘録

Tracing Ruby Applications