Adding Vertex AI Imagen models support

[Marzouki-Sami]

Closes gh-2133

Signed-off-by: Marzouki-Sami samymarzouki502@gmail.com

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You might have already read the [contributor guide][1], but as a reminder, please make sure to:

• Sign the contributor license agreement
• Rebase your changes on the latest main branch and squash your commits
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• Run a build and make sure all tests pass prior to submission

[markpollack]

@ddobrin can you please take a look?

[turchinc]

Any update here? I am also interested in this feature.

[byungjunn]

I am currently using this feature as a custom-made version. I hope it gets updated soon. If help is needed, I would be willing to participate.

[ilayaperumalg]

@byungjunn Thanks! Any help reviewing the PR is much appreciated.

[byungjunn]

@Marzouki-Sami
https://spring.io/blog/2025/03/25/spring-ai-update-to-snapshots
After the update, there have been many changes, so I think you need to rebase onto the main branch.

[Marzouki-Sami]

@byungjunn @ilayaperumalg @markpollack i had some issues with resolving the conflict and to resolve the conflict i had to remove the commits, doing that closed this PR is it possible to reopen it, if not i will create a new PR and link it to this one.

[Marzouki-Sami]

@byungjunn thanks for the review the mentioned points above are fixed. Can you check them?

[Marzouki-Sami]

Any updates?

[Marzouki-Sami]

Just a minor change added in the last commit (f341567). Switching the constructor params ( mimetype and model) of VertexAiImagenImageGenerationMetadata to be in the same order of usage in VertexAiImagenImageModel ( line 177)

[Marzouki-Sami]

@byungjunn can you review pls.

[Marzouki-Sami]

@markpollack @ilayaperumalg @ddobrin @byungjunn Any updates? If not, will it take much longer?

[Marzouki-Sami]

@markpollack @ilayaperumalg @ddobrin How much time does it take to get a response on the previous comment?

[Marzouki-Sami]

@byungjunn It has been over four months since I requested a review. Are you still available for review, or should this be passed to another person to review it?

[byungjunn]

@byungjunn It has been over four months since I requested a review. Are you still available for review, or should this be passed to another person to review it?

@Marzouki-Sami Long time no see. I’ve been busy with a lot of things, so we haven’t caught up in a while. I’ve reviewed it enough, and I think it might be better now for the people who actually have the authority to merge to take a look.

[Marzouki-Sami]

@markpollack @ilayaperumalg @ddobrin What’s next? The latest changes have been reviewed and approved by @byungjunn. If another reviewer is needed, please assign one.

[Marzouki-Sami]

@markpollack @ilayaperumalg @ddobrin This pull request has been open for over a year without a response to previous mentions. I understand the team may be busy, so if you don't have the capacity to review this at the moment, could you please delegate the review to another team member with write access?

[Marzouki-Sami]

@markpollack @ilayaperumalg @ddobrin Another conflict occurred, and there has still been no response to any of the previous comments.

[OreOreDa]

I created another clean PR, in order to solve the issue : #2133
Please have a look

[ddobrin]

Hi @OreOreDa
please note that the Imagen models will be deprecated soon, as per this schedule deprecations.

I would recommend migrating to the Gemini 3.x pro image models beforehand, while using the Google GenAI SDK.

Thank you

cc @ilayaperumalg @sdeleuze

[OreOreDa]

@ddobrin @ilayaperumalg @sdeleuze

My new PR for Google GenAI image models
I integrated the latest refacto, and the latest GenAI sdk updates - tested with "gemini-2.5-flash-image" so far
Can you have a look at it, please ?