[Bug]: Vertex AI completion proxy requests fail with OAuth error

[chrisgnicholas]

What happened?

Attempts at a VertexAI completion fail with the error: 401 Request had invalid authentication credentials.

Attached is a redacted stacktrace (redacted to address issue 8075).

When creating the entry in LiteLLM, at the step "upload credentials", we are submitting a document of the form, that we are pretty confident is current:

{
"type": "service_account",
"project_id": "our-google-project-id",
"private_key_id": "1234567890asdfghjkl",
"private_key": "-----BEGIN PRIVATE KEY——\lotsofrandomcharacters \——END PRIVATE KEY-----\n",
"client_email": "foo@our-google-project-id.iam.gserviceaccount.com",
"client_id": "0987654321",
"auth_uri": "https://accounts.google.com/o/oauth2/auth",
"token_uri": "https://oauth2.googleapis.com/token",
"auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
"client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/svc-genai-ai-gateway-npe%40humsrd-edsai-vertexai-npe-7fdb.iam.gserviceaccount.com",
"universe_domain": "googleapis.com"
}

Relevant log output

[vertex_auth_errs.log](https://github.com/user-attachments/files/18590261/vertex_auth_errs.log)

Are you a ML Ops Team?

No

What LiteLLM version are you on ?

main-v1.59.3

Twitter / LinkedIn details

No response