Go client doesn't allow embedding response to be base64 encoded string

[aliok]

Similar to openai/openai-openapi#424

The embedding field of the Embedding object will be a string, if encoding_format is set to base64.

E.g.

curl -v https://api.openai.com/v1/embeddings \
-H "Authorization: Bearer $OPENAI_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"input": "The food was delicious",
"model": "text-embedding-3-small",
"encoding_format": "base64",
"dimensions":10
}'

{
  "object": "list",
  "data": [
    {
      "object": "embedding",
      "index": 0,
      "embedding": "nMcovm6gOb7ldwO/AESlvk0Avz2nZIq+3c+EvZvdFT9HsZa9oSy+vg=="    <------ THIS
    }
  ],
  "model": "text-embedding-3-small",
  "usage": {
    "prompt_tokens": 4,
    "total_tokens": 4
  }
}

However, the client mandates that the embedding field is an array of floats.

openai-go/embedding.go

Lines 115 to 124 in 7ad3660

	type Embedding struct {
	// The embedding vector, which is a list of floats. The length of vector depends on
	// the model as listed in the
	// [embedding guide](https://platform.openai.com/docs/guides/embeddings).
	Embedding []float64 `json:"embedding,required"`
	// The index of the embedding in the list of embeddings.
	Index int64 `json:"index,required"`
	// The object type, which is always "embedding".
	Object EmbeddingObject `json:"object,required"`
	JSON embeddingJSON `json:"-"`

[jacobzim-stl]

It's interesting that it's not in the OpenAPI specification, I'll get back to you on that.

In the meantime, the base64 encoded embedding is accessible via the .JSON metadata field

resp, _ := client.Embeddings.New(ctx, openai.EmbeddingNewParams{
	Model: openai.EmbeddingModelTextEmbedding3Small,
	Input: openai.EmbeddingNewParamsInputUnion{
		OfString: openai.String(question),
	},
	EncodingFormat: openai.EmbeddingNewParamsEncodingFormatBase64,
})

var b64embedding string
json.Unmarshal([]byte(resp.Data[0].JSON.Embedding.Raw()), &b64embedding)
println(b64embedding)