[Vertex AI] Add a responseMimeType to generationConfig

[DellaBitta]

Discussion

Provide Apps with an ability to configure the responseMimeType. This enables applications to request that VertexAI returns the response in a JSON format instead of a normal textual format.

Testing

Local app testing.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 70a2f7a

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[google-oss-bot]

Size Report ¹

Affected Products

No changes between base commit (d79a131) and merge commit (79a69fe).

Test Logs

• Base (d79a131): https://github.com/firebase/firebase-js-sdk/actions/runs/9005885410
• Merge (79a69fe): https://github.com/firebase/firebase-js-sdk/actions/runs/9007401679

1. https://storage.googleapis.com/firebase-sdk-metric-reports/HF3Opum1iN.html

[hsubox76]

One comment to add documentation, otherwise looks good!

[google-oss-bot]

Size Analysis Report ¹

Affected Products

No changes between base commit (d79a131) and merge commit (79a69fe).

Test Logs

• Base (d79a131): https://github.com/firebase/firebase-js-sdk/actions/runs/9005885410
• Merge (79a69fe): https://github.com/firebase/firebase-js-sdk/actions/runs/9007401679

1. https://storage.googleapis.com/firebase-sdk-metric-reports/KP1Jyvw5fL.html