marshallpierce/easyracer

Easy Racer

This project explores how easy it is to build programs which can "race" two or more concurrent computations while providing:

• loser cancellation
• resource management
• efficient thread utilization (i.e. reactive, non-blocking)
• explicit timeouts
• errors causing a race loss

A scenario server validates the implementations of 8 scenarios:

1. Race 2 concurrent requests

   GET /1
   

2. Race 2 concurrent requests, where one produces a connection error

   GET /2
   

3. Race 10,000 concurrent requests

   GET /3
   

4. Race 2 concurrent requests but 1 of them should have a 1 second timeout

   GET /4
   

5. Race 2 concurrent requests where the winner is a 20x response

   GET /5
   

6. Race 3 concurrent requests where the winner is a 20x response

   GET /6
   

7. Start a request, wait at least 3 seconds then start a second request (hedging)

   GET /7
   

8. Race 2 concurrent requests that "use" a resource which is obtained and released through other requests. The "use" request can return a non-20x request, in which case it is not a winner.

   GET /8?open
   GET /8?use=<id obtained from open request>
   GET /8?close=<id obtained from open request>
   

9. Make 10 concurrent requests where 5 return a 200 response with a letter, when assembled in order of when they responded, form the "right" answer

   GET /9
   

If your implementation is correct, each race will result in a 200 response with a body:

right

The scenario server has a public container ghcr.io/jamesward/easyracer and if you contribute your client to this repo, use Testcontainers and include automated integration tests.

Clients

Name	Source	Tests
Scala 3 + ZIO	scala-zio
Kotlin + Splitties	kotlin-splitties
Kotlin + Arrow	kotlin-arrow
Java + Loom	java-loom
Python + AIOHTTP	python-aiohttp