reactioncommerce/reaction

cancelOrderItem can't deal with concurrent requests properly

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#6493 opened on Jan 20, 2021

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 (16 comments) (1 reaction) (0 assignees)JavaScript (12,181 stars) (2,198 forks)batch import
buggood first issueneeds triage

Description

Issue Description

If cancelOrderItem is fired in parallel for multiple fulfillment groups of an order, only some of them might receive an update. You can see this in action on the current order admin, which fires them in parallel if you click "Cancel Order" (Might be reconsidered in general, network errors should not result in an order being partially cancelled.)

Steps to Reproduce

  1. Create an order with two fulfillment groups
  2. Click "Cancel order" in the admin
  3. Notice that only one of the fulfillment groups updated their status

Possible Solution

The reason for this is that the mutation will process the whole shipping array of an order in memory and write that to the db - Parallel updates to it will get lost. Options could either be to add some locking mechanism on this, or to just to rewrite this to make atomic operations instead of replacing the whole array.

Versions

latest

Contributor guide

Tech stack
javascriptnodejsgraphqlmongodb
Domain
backenddatabaseperformance
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
mostly clear
Prerequisites
Node.js async/awaitGraphQL mutationsMongoDB atomic updates
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30
Research direction
Locate the cancelOrderItem mutation in the codebase and identify where the shipping array is read and written. Propose using MongoDB's atomic operators like $elemMatch or $set to update specific array elements without replacing the whole array. Alternatively, implement a locking mechanism. Write concurrency tests using tools like Artillery to verify correctness under parallel requests.