[js] add --websocket-port flag when not connecting to existing connection on firefox

[Delta456]

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By having the --websocket-port parameter by default we avoid port collisions when using BiDi with firefox

Motivation and Context

Fixes #15451 for JS binding

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

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PR Type

Bug fix, Enhancement

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Description

• Added --websocket-port flag for Firefox to avoid port conflicts.

• Integrated portprober to dynamically allocate free ports.

• Ensured the flag is only applied when not connecting to an existing instance.

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Changes walkthrough 📝

	Relevant files
Enhancement	index.js Add dynamic `--websocket-port` allocation for Firefox        javascript/selenium-webdriver/index.js Imported portprober for dynamic port allocation. Added logic to append --websocket-port with a free port for Firefox. Ensured the flag is skipped when connecting to an existing instance. +7/-0

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[qodo-merge-pro]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🎫 Ticket compliance analysis ✅ 15451 - PR Code Verified Compliant requirements: • Added support for the websocket-port argument to avoid port collisions when using BiDi with Firefox Requires further human verification: • Verify that the implementation properly fixes the issue with multiple sessions on the same geckodriver • Confirm that the solution is consistent with how Python and .NET bindings handle this

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Method Error The code uses service?.args.append() but the correct method for arrays in JavaScript is likely push() not append(). This will cause runtime errors. service?.args.append('--websocket-port') service?.args.append(`${portprober.findFreePort()}`) Race Condition The port is allocated but not reserved, which could lead to a race condition where another process takes the port between finding it and starting Firefox. service?.args.append(`${portprober.findFreePort()}`)

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
Possible issue	✅ Use correct array method Suggestion Impact: The commit directly implemented the suggestion by changing the incorrect 'append' method to the correct 'push' method for adding elements to JavaScript arrays, fixing a critical bug that would have caused runtime errors code diff: - service?.args.append('--websocket-port') - service?.args.append(`${portprober.findFreePort()}`) + service?.args.push('--websocket-port') + service?.args.push(`${portprober.findFreePort()}`) The args property likely doesn't have an append method. You should use push instead, which is the standard method for adding elements to arrays in JavaScript. javascript/selenium-webdriver/index.js [685-688] if (!service?.args.includes('--connect-existing')) { - service?.args.append('--websocket-port') - service?.args.append(`${portprober.findFreePort()}`) + service?.args.push('--websocket-port') + service?.args.push(`${portprober.findFreePort()}`) } [Suggestion has been applied] Suggestion importance[1-10]: 10 __ Why: The suggestion correctly identifies a critical bug. JavaScript arrays use the push() method to add elements, not append(). Using append() would cause a runtime error that would break the Firefox driver initialization.	High
Update

[pujagani]

I think all the Firefox tests are failing. Can you help take a look? @Delta456
Thank you!

[pujagani]

It looks fine but there must be a reason for tests failing. Do they pass on your local machine? Wondering if this is RBE specific

[Delta456]

It looks fine but there must be a reason for tests failing. Do they pass on your local machine? Wondering if this is RBE specific

Yes, they are passing locally. I am trying to figure out why it is failing on CI only.

[harsha509]

Thank you @Delta456 !

[harsha509]

Hi @Delta456,

Thank you for your PR. The fix appeared correct, but it didn't replace the port as expected.

I've updated the implementation in PR #15557.
I'm closing this one—apologies for the oversight.

Thank you @pujagani for taking a look.