@azure/cosmos: request handler - fix 'abortSignal' and event listener memory leak

[petriposio]

Packages impacted by this PR

@azure/cosmos

Issues associated with this PR

Describe the problem that is addressed by this PR

In sdk/cosmosdb/cosmos/src/request/RequestHandler.ts an event listener is added to the abortSignal. The event listener is never removed. This causes a memory leak.

This bug might also eventually lead to the user provided abort signal to be ignored if events.setMaxListeners is configured in NodeJS.

A reproducible example

import { CosmosClient } from "@azure/cosmos";

const endpoint = "https://your-account.documents.azure.com";
const key = "<database account masterkey>";
const client = new CosmosClient({ endpoint, key });

const { database } = await client.databases.createIfNotExists({ id: "Test Database" });
const { container } = await database.containers.createIfNotExists({ id: "Test Container" });

const abortSignal = AbortSignal.timeout(5 * 60 * 1e3);

const query = container.items.query(
  {
    query: "SELECT * FROM c",
  },
  {
    abortSignal,
    maxItemCount: 1,
  }
);

for await (const response of query.getAsyncIterator()) {
  /*
   *
   * The EventListener added to the 'abortSignal' is not removed and thus it is leaking memory
   *
   * In NodeJS unless events.setMaxListeners is set to Infinity, will effectively eventually cause 'abortSignal' to be rejected and ignored
   *
   * MaxListenersExceededWarning: Possible EventTarget memory leak detected. 11 abort listeners added to [AbortSignal]. MaxListeners is 10. Use events.setMaxListeners() to increase limit
   *
   */
// 
}

What are the possible designs available to address the problem? If there are more than one possible design, why was the one in this PR chosen?

Are there test cases added in this PR? (If not, why?)

Provide a list of related PRs (if any)

Command used to generate this PR:**(Applicable only to SDK release request PRs)

Checklists

• Added impacted package name to the issue description
• Does this PR needs any fixes in the SDK Generator?** (If so, create an Issue in the Autorest/typescript repository and link it here)
• Added a changelog (if necessary)

[github-actions]

Thank you for your contribution @petriposio! We will review the pull request and get back to you soon.

[xirzec]

@jeremymeng I remember you've dealt with similar leaks in the past, does this fix look correct?

[jeremymeng]

This fix looks good to me. Thanks for your contribution @petriposio!

@amanrao23 @aditishree1 please have a look

[github-actions]

Hi @petriposio. Thank you for your interest in helping to improve the Azure SDK experience and for your contribution. We've noticed that there hasn't been recent engagement on this pull request. If this is still an active work stream, please let us know by pushing some changes or leaving a comment. Otherwise, we'll close this out in 7 days.

[petriposio]

Still active. Waiting for a review. Could the code owners have a look, please? Is there anything I can do to get this merged?

[aditishree1]

LGTM