Transcription API response is missing diarized data for response_format=diarized_json

Issue

When you try to use openAiClient.audio().transcriptions().create(createParams) with response format AudioResponseFormat.DIARIZED_JSON, the returned instance of TranscriptionCreateResponse does not have a value for the diarized field; and instead contains the entire raw JSON response in the text field of the transcription.

Expected behavior

TranscriptionCreateResponse#diarized() returns a non-empty Optional with the contents of the diarized response.

Workaround

We can read the raw JSON string and manually parse it.

new ObjectMapper().readValue(response.transcription().get().text(), TranscriptionDiarized.class)

Possible cause

From what I can tell from a little bit of debugging, the issue might be here in the AudioResponseFormat#isJson function, where a case for DIARIZED_JSON is missing. As a result, the parser considers the response to be plain text.

https://github.com/openai/openai-java/blob/5729c58d66faa09cde2ea8dc6293411b200cbd86/openai-java-core/src/main/kotlin/com/openai/models/audio/AudioResponseFormat.kt#L155-L162

Example

An example input/output where I observed the issue:

TranscriptionCreateParams{body=Body{file=MultipartField{value=sun.nio.ch.ChannelInputStream@967d60f, contentType=audio/mpeg, filename=sousei_no_onmyouji_short.mp3}, model=MultipartField{value=gpt-4o-transcribe-diarize, contentType=text/plain; charset=utf-8, filename=null}, chunkingStrategy=MultipartField{value=ChunkingStrategy{auto=auto}, contentType=text/plain; charset=utf-8, filename=null}, include=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, knownSpeakerNames=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, knownSpeakerReferences=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, language=MultipartField{value=ja, contentType=text/plain; charset=utf-8, filename=null}, prompt=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, responseFormat=MultipartField{value=diarized_json, contentType=text/plain; charset=utf-8, filename=null}, temperature=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, timestampGranularities=MultipartField{value=null, contentType=text/plain; charset=utf-8, filename=null}, additionalProperties={}}, additionalHeaders=Headers{map={}}, additionalQueryParams=QueryParams{map={}}}

This results in the following. Note that the text field of transcription contains the entire JSON string, but diarized is missing / null.

TranscriptionCreateResponse{transcription=Transcription{text={"text":"彼女の名はアダ シノベリオ 強力な怨霊を排出 してきた京都の名家ア ダシノ家の筆頭","segments":[{"type":"transcript.text.segment","text":"彼女の名はアダシノベリオ","speaker":"A","start":1.0000000000000002,"end":3.3,"id":"seg_0"},{"type":"transcript.text.segment","text":"強力な怨霊を排出してきた京都の名家アダシノ家の筆頭","speaker":"A","start":3.8,"end":9.4,"id":"seg_1"}],"usage":{"type":"tokens","total_tokens":405,"input_tokens":97,"input_token_details":{"text_tokens":0,"audio_tokens":97},"output_tokens":308}}, logprobs=, usage=, additionalProperties={}}}

Remark

The JSON data itself seems correct, when I try to parse the raw JSON manually into an instance of TranscriptionDiarized, it works:

Start in openai-java-core/src/main/kotlin/com/openai/models/audio/AudioResponseFormat.kt around AudioResponseFormat#isJson, using the issue's DIARIZED_JSON request example as the reproduction. Verify that the response is parsed as TranscriptionDiarized rather than plain text. Done means TranscriptionCreateResponse#diarized() contains the returned diarized data instead of placing the raw JSON in transcription.text.