embed.go•4.85 kB
// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// SPDX-License-Identifier: Apache-2.0
package ollama
import (
"bytes"
"context"
"encoding/json"
"fmt"
"net/http"
"strings"
"github.com/firebase/genkit/go/ai"
"github.com/firebase/genkit/go/core/api"
"github.com/firebase/genkit/go/genkit"
)
type EmbedOptions struct {
Model string `json:"model"`
}
type ollamaEmbedRequest struct {
Model string `json:"model"`
Input any `json:"input"` // todo: using any to handle both string and []string, figure out better solution
Options map[string]any `json:"options,omitempty"`
}
type ollamaEmbedResponse struct {
Embeddings [][]float32 `json:"embeddings"`
}
func embed(ctx context.Context, serverAddress string, req *ai.EmbedRequest) (*ai.EmbedResponse, error) {
options, ok := req.Options.(*EmbedOptions)
if !ok && req.Options != nil {
return nil, fmt.Errorf("invalid options type: expected *EmbedOptions")
}
if options == nil || options.Model == "" {
return nil, fmt.Errorf("invalid embedding model: model must be specified")
}
if serverAddress == "" {
return nil, fmt.Errorf("invalid server address: address cannot be empty")
}
ollamaReq := newOllamaEmbedRequest(options.Model, req.Input)
jsonData, err := json.Marshal(ollamaReq)
if err != nil {
return nil, fmt.Errorf("failed to marshal embed request: %w", err)
}
resp, err := sendEmbedRequest(ctx, serverAddress, jsonData)
if err != nil {
return nil, err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return nil, fmt.Errorf("ollama embed request failed with status code %d", resp.StatusCode)
}
var ollamaResp ollamaEmbedResponse
if err := json.NewDecoder(resp.Body).Decode(&ollamaResp); err != nil {
return nil, fmt.Errorf("failed to decode embed response: %w", err)
}
return newEmbedResponse(ollamaResp.Embeddings), nil
}
func sendEmbedRequest(ctx context.Context, serverAddress string, jsonData []byte) (*http.Response, error) {
client := &http.Client{}
httpReq, err := http.NewRequestWithContext(ctx, "POST", serverAddress+"/api/embed", bytes.NewBuffer(jsonData))
if err != nil {
return nil, fmt.Errorf("failed to create request: %w", err)
}
httpReq.Header.Set("Content-Type", "application/json")
return client.Do(httpReq)
}
func newOllamaEmbedRequest(model string, documents []*ai.Document) ollamaEmbedRequest {
var input any
if len(documents) == 1 {
input = concatenateText(documents[0])
} else {
texts := make([]string, len(documents))
for i, doc := range documents {
texts[i] = concatenateText(doc)
}
input = texts
}
return ollamaEmbedRequest{
Model: model,
Input: input,
}
}
func newEmbedResponse(embeddings [][]float32) *ai.EmbedResponse {
resp := &ai.EmbedResponse{
Embeddings: make([]*ai.Embedding, len(embeddings)),
}
for i, embedding := range embeddings {
resp.Embeddings[i] = &ai.Embedding{Embedding: embedding}
}
return resp
}
func concatenateText(doc *ai.Document) string {
var builder strings.Builder
for _, part := range doc.Content {
builder.WriteString(part.Text)
}
result := builder.String()
return result
}
// DefineEmbedder defines an embedder with a given server address.
func (o *Ollama) DefineEmbedder(g *genkit.Genkit, serverAddress string, model string, embedOpts *ai.EmbedderOptions) ai.Embedder {
o.mu.Lock()
defer o.mu.Unlock()
if !o.initted {
panic("ollama.Init not called")
}
return genkit.DefineEmbedder(g, api.NewName(provider, serverAddress), embedOpts, func(ctx context.Context, req *ai.EmbedRequest) (*ai.EmbedResponse, error) {
if req.Options == nil {
req.Options = &EmbedOptions{Model: model}
}
if req.Options.(*EmbedOptions).Model == "" {
req.Options.(*EmbedOptions).Model = model
}
return embed(ctx, serverAddress, req)
})
}
// IsDefinedEmbedder reports whether the embedder with the given server address is defined by this plugin.
func IsDefinedEmbedder(g *genkit.Genkit, serverAddress string) bool {
return genkit.LookupEmbedder(g, api.NewName(provider, serverAddress)) != nil
}
// Embedder returns the [ai.Embedder] with the given server address.
// It returns nil if the embedder was not defined.
func Embedder(g *genkit.Genkit, serverAddress string) ai.Embedder {
return genkit.LookupEmbedder(g, api.NewName(provider, serverAddress))
}