Support OpenAI embedding. (#1542)

plugins/wasm-go/extensions/ai-cache/embedding/openai.go

@@ -0,0 +1,156 @@
+package embedding
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
+	"net/http"
+)
+
+const (
+	OPENAI_DOMAIN             = "api.openai.com"
+	OPENAI_PORT               = 443
+	OPENAI_DEFAULT_MODEL_NAME = "text-embedding-3-small"
+	OPENAI_ENDPOINT           = "/v1/embeddings"
+)
+
+type openAIProviderInitializer struct {
+}
+
+func (t *openAIProviderInitializer) ValidateConfig(config ProviderConfig) error {
+	if config.apiKey == "" {
+		return errors.New("[OpenAI] embedding service ApiKey is required")
+	}
+	return nil
+}
+
+func (t *openAIProviderInitializer) CreateProvider(c ProviderConfig) (Provider, error) {
+	if c.servicePort == 0 {
+		c.servicePort = OPENAI_PORT
+	}
+	if c.serviceHost == "" {
+		c.serviceHost = OPENAI_DOMAIN
+	}
+	if c.model == "" {
+		c.model = OPENAI_DEFAULT_MODEL_NAME
+	}
+	return &OpenAIProvider{
+		config: c,
+		client: wrapper.NewClusterClient(wrapper.FQDNCluster{
+			FQDN: c.serviceName,
+			Host: c.serviceHost,
+			Port: c.servicePort,
+		}),
+	}, nil
+}
+
+func (t *OpenAIProvider) GetProviderType() string {
+	return PROVIDER_TYPE_OPENAI
+}
+
+type OpenAIResponse struct {
+	Object string         `json:"object"`
+	Data   []OpenAIResult `json:"data"`
+	Model  string         `json:"model"`
+	Error  *OpenAIError   `json:"error"`
+}
+
+type OpenAIResult struct {
+	Object    string    `json:"object"`
+	Embedding []float64 `json:"embedding"`
+	Index     int       `json:"index"`
+}
+
+type OpenAIError struct {
+	Message string `json:"prompt_tokens"`
+	Type    string `json:"type"`
+	Code    string `json:"code"`
+	Param   string `json:"param"`
+}
+
+type OpenAIEmbeddingRequest struct {
+	Input string `json:"input"`
+	Model string `json:"model"`
+}
+
+type OpenAIProvider struct {
+	config ProviderConfig
+	client wrapper.HttpClient
+}
+
+func (t *OpenAIProvider) constructParameters(text string, log wrapper.Log) (string, [][2]string, []byte, error) {
+	if text == "" {
+		err := errors.New("queryString text cannot be empty")
+		return "", nil, nil, err
+	}
+
+	data := OpenAIEmbeddingRequest{
+		Input: text,
+		Model: t.config.model,
+	}
+
+	requestBody, err := json.Marshal(data)
+	if err != nil {
+		log.Errorf("failed to marshal request data: %v", err)
+		return "", nil, nil, err
+	}
+
+	headers := [][2]string{
+		{"Authorization", fmt.Sprintf("Bearer %s", t.config.apiKey)},
+		{"Content-Type", "application/json"},
+	}
+
+	return OPENAI_ENDPOINT, headers, requestBody, err
+}
+
+func (t *OpenAIProvider) parseTextEmbedding(responseBody []byte) (*OpenAIResponse, error) {
+	var resp OpenAIResponse
+	err := json.Unmarshal(responseBody, &resp)
+	if err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (t *OpenAIProvider) GetEmbedding(
+	queryString string,
+	ctx wrapper.HttpContext,
+	log wrapper.Log,
+	callback func(emb []float64, err error)) error {
+	embUrl, embHeaders, embRequestBody, err := t.constructParameters(queryString, log)
+	if err != nil {
+		log.Errorf("failed to construct parameters: %v", err)
+		return err
+	}
+
+	var resp *OpenAIResponse
+	err = t.client.Post(embUrl, embHeaders, embRequestBody,
+		func(statusCode int, responseHeaders http.Header, responseBody []byte) {
+
+			if statusCode != http.StatusOK {
+				err = fmt.Errorf("failed to get embedding due to status code: %d, resp: %s", statusCode, responseBody)
+				callback(nil, err)
+				return
+			}
+
+			resp, err = t.parseTextEmbedding(responseBody)
+			if err != nil {
+				err = fmt.Errorf("failed to parse response: %v", err)
+				callback(nil, err)
+				return
+			}
+
+			log.Debugf("get embedding response: %d, %s", statusCode, responseBody)
+
+			if len(resp.Data) == 0 {
+				err = errors.New("no embedding found in response")
+				callback(nil, err)
+				return
+			}
+
+			callback(resp.Data[0].Embedding, nil)
+
+		}, t.config.timeout)
+	return err
+}

plugins/wasm-go/extensions/ai-cache/embedding/provider.go

@@ -10,6 +10,7 @@ import (
 const (
 	PROVIDER_TYPE_DASHSCOPE = "dashscope"
 	PROVIDER_TYPE_TEXTIN    = "textin"
+	PROVIDER_TYPE_OPENAI    = "openai"
 )
 
 type providerInitializer interface {
@@ -21,6 +22,7 @@ var (
 	providerInitializers = map[string]providerInitializer{
 		PROVIDER_TYPE_DASHSCOPE: &dashScopeProviderInitializer{},
 		PROVIDER_TYPE_TEXTIN:    &textInProviderInitializer{},
+		PROVIDER_TYPE_OPENAI:    &openAIProviderInitializer{},
 	}
 )