Add WebP image support for multimodality

[laurentperez]

Please do a quick search on GitHub issues first, the feature you are about to request might have already been requested. => I searched for "webp".

Expected Behavior

WebP images can be used in multimodality

Current Behavior

Currently no constant is available for WebP in https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/util/MimeTypeUtils.html which is used by Spring AI Media class.

Context

How has this issue affected you?

Currently my company has a PDF to WebP converter pipeline and we'd like to then send these webp images to a LLM supporting multimodality.

[codingkiddo]

Thanks for reporting this.

I checked the current OpenAiChatOptions implementation and it looks like promptCacheKey is indeed missing, while the reference documentation still lists spring.ai.openai.chat.options.prompt-cache-key.

I’d be happy to work on a small PR to restore this option if the team agrees with that direction.

The change would likely include:

• adding promptCacheKey to OpenAiChatOptions
• adding builder/getter/mutate/equality coverage
• mapping it to the OpenAI chat completion request
• adding focused tests for the builder/property binding/request mapping