README.md

AppMap + GraphQL + Fiber Bug

This app replicates the bug reported at getappmap/appmap-ruby#349.

Conditions

• Using the appmap gem
• Using the latest graphql gem
• config.active_support.isolation_level = :fiber in application.rb

Steps to reproduce

1. Prepare app

git clone git@github.com:coderberry/appmap-test-app-fiber-graphql.git
cd appmap-test-app-fiber-graphql
bin/setup
bin/rails db:migrate
bin/rails db:seed

2. Run the app

bin/rails s

3. Execute a query via GraphiQL

Open http://locahost:3000/graphiql) and execute the following query 5 times:

query {
  localCounts
}

4. Observe the hung fibers

Ensure you are viewing the Rails server logs and sumbmit the request a 6th time. The request will hang and you will see that the connection pool was not cleaned up.

Example: