fix(stt): append api-version for Azure OpenAI Whisper endpoint

[wwenrr]

Summary

Fixes Azure OpenAI Whisper transcription failures by appending api-version when configured.

What changed

• Added openaiApiVersion config value from env:
  • OPENAI_API_VERSION
  • AZURE_OPENAI_API_VERSION (fallback alias)
• Updated server/services/openai-whisper.ts to build request URL dynamically:
  • uses existing OPENAI_WHISPER_URL by default
  • appends ?api-version=<value> when version env is set
  • preserves existing api-version if already present in URL
• Added focused tests in server/services/openai-whisper.test.ts for all three URL behaviors.

Verification

• npx vitest run server/services/openai-whisper.test.ts server/routes/transcribe.test.ts
• npm run build:server

Fixes #171

Summary by CodeRabbit

• New Features

  • Server configuration now supports specifying an OpenAI API version.
  • Whisper transcription requests respect the configured API version and preserve existing URL parameters when present.

• Tests

  • Added test coverage for API-version handling in transcription request URLs.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: b5325f74-297c-4464-a2c1-ebeb6710fbd7

📥 Commits

Reviewing files that changed from the base of the PR and between d282e03 and 1d5c1b9.

📒 Files selected for processing (1)

• server/services/openai-whisper.test.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• server/services/openai-whisper.test.ts

---

📝 Walkthrough

Walkthrough

Adds openaiApiVersion to server config and updates Whisper transcription URL construction to append an api-version query parameter when configured; includes tests covering URL-building behavior for empty, set, existing, and whitespace-only version values.

Changes

Cohort / File(s)	Summary
Configuration server/lib/config.ts	Exported openaiApiVersion: string on config, sourced from process.env.OPENAI_API_VERSION or process.env.AZURE_OPENAI_API_VERSION, defaulting to empty string.
OpenAI Whisper Implementation server/services/openai-whisper.ts	Added non-exported getWhisperUrl() to conditionally inject api-version into OPENAI_WHISPER_URL (trims config.openaiApiVersion); transcribe() now calls this helper.
Tests server/services/openai-whisper.test.ts	New Vitest suite verifying URL construction and fetch invocation across four scenarios: no version, version set, URL already contains api-version, and whitespace-only version. Stubs fetch and mocks config/constants.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 I hopped through config, keen and spry,
To tuck an api-version in the sky,
URLs stitched with careful art,
No more 404s to break the heart,
Whisper sings, and I do a happy hop 🎵

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'fix(stt): append api-version for Azure OpenAI Whisper endpoint' accurately summarizes the primary change - adding api-version parameter support for Azure OpenAI.
Description check	✅ Passed	The description covers the main changes, references the linked issue, and includes verification steps. While not using the exact template format, all essential information is present and well-organized.
Linked Issues check	✅ Passed	The PR fully addresses issue #171 by introducing environment variable support (OPENAI_API_VERSION/AZURE_OPENAI_API_VERSION), implementing dynamic URL building with api-version appending, and preserving existing api-version parameters.
Out of Scope Changes check	✅ Passed	All changes are scoped to the linked issue requirements: config field addition, URL building logic, and comprehensive test coverage for the feature.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[coderabbitai]

🧹 Nitpick comments (1)

server/services/openai-whisper.test.ts (1)

14-82: Good test coverage for the three URL construction scenarios.

The tests correctly verify:

1. Base URL unchanged when no API version configured
2. api-version query param appended when configured
3. Existing api-version in URL is preserved (not overwritten)

Consider adding a test for whitespace-only openaiApiVersion (e.g., ' ') to verify the .trim() behavior works as expected, ensuring it falls back to the base URL.

💡 Optional: Add edge case test for whitespace-only API version

it('uses base whisper URL when API version is whitespace-only', async () => {
  vi.doMock('../lib/config.js', () => ({
    config: { openaiApiKey: 'sk-test', openaiApiVersion: '   ', language: 'en' },
  }));

  vi.doMock('../lib/constants.js', () => ({
    OPENAI_WHISPER_URL: 'https://api.openai.com/v1/audio/transcriptions',
  }));

  vi.mocked(fetch).mockResolvedValue(
    new Response(JSON.stringify({ text: 'ok' }), { status: 200 }),
  );

  const { transcribe } = await import('./openai-whisper.js');
  await transcribe(Buffer.from('abc'), 'sample.webm');

  expect(fetch).toHaveBeenCalledWith(
    'https://api.openai.com/v1/audio/transcriptions',
    expect.objectContaining({ method: 'POST' }),
  );
});

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@server/services/openai-whisper.test.ts` around lines 14 - 82, Add a test in
openai-whisper.test.ts that mocks config.config.openaiApiVersion to a
whitespace-only string (e.g., '   '), mocks OPENAI_WHISPER_URL to the base URL,
stubs fetch to return a successful Response, imports transcribe from
./openai-whisper.js, calls transcribe(Buffer.from('abc'), 'sample.webm'), and
asserts fetch was called with the base OPENAI_WHISPER_URL (no ?api-version
appended); reference the transcribe function, config.openaiApiVersion, and
OPENAI_WHISPER_URL when locating where to add the new test and reuse the
existing fetch mock setup/assertion pattern from the other tests.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@server/services/openai-whisper.test.ts`:
- Around line 14-82: Add a test in openai-whisper.test.ts that mocks
config.config.openaiApiVersion to a whitespace-only string (e.g., '   '), mocks
OPENAI_WHISPER_URL to the base URL, stubs fetch to return a successful Response,
imports transcribe from ./openai-whisper.js, calls
transcribe(Buffer.from('abc'), 'sample.webm'), and asserts fetch was called with
the base OPENAI_WHISPER_URL (no ?api-version appended); reference the transcribe
function, config.openaiApiVersion, and OPENAI_WHISPER_URL when locating where to
add the new test and reuse the existing fetch mock setup/assertion pattern from
the other tests.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: df4de8c7-b586-410f-984f-6712a9383a68

📥 Commits

Reviewing files that changed from the base of the PR and between fed3ab1 and d282e03.

📒 Files selected for processing (3)

• server/lib/config.ts
• server/services/openai-whisper.test.ts
• server/services/openai-whisper.ts

[wwenrr]

Addressed the CodeRabbit suggestion ✅\n\nAdded a new test case for whitespace-only API version config:\n- now verifies we keep the base \n- Ensures no is appended when the configured value trims to empty\n\nPushed in commit: \n\nNote: I couldn't run the local test command in this environment because isn't installed here, but the test follows the existing test harness/mocking pattern in this file.