feat(openai): use go-openai client (#295)

Because

- Originally, we used `httpclient` to connect directly to OpenAI. Since
we are introducing the streaming feature, using the `go-openai` SDK will
make the codebase easier to maintain.

This commit

- Switches to using the `go-openai` client.

ai/openai/v0/audio_transcriptions.go

@@ -1,57 +1,9 @@
 package openai
 
-import (
-	"bytes"
-	"fmt"
-	"mime/multipart"
-
-	"github.com/instill-ai/component/internal/util"
-)
-
-const (
-	transcriptionsPath = "/v1/audio/transcriptions"
-)
-
 type AudioTranscriptionInput struct {
-	Audio       string   `json:"audio"`
-	Model       string   `json:"model"`
-	Prompt      *string  `json:"prompt,omitempty"`
-	Temperature *float64 `json:"temperature,omitempty"`
-	Language    *string  `json:"language,omitempty"`
-}
-
-type AudioTranscriptionReq struct {
-	File           []byte   `json:"file"`
-	Model          string   `json:"model"`
-	Prompt         *string  `json:"prompt,omitempty"`
-	Language       *string  `json:"language,omitempty"`
-	Temperature    *float64 `json:"temperature,omitempty"`
-	ResponseFormat string   `json:"response_format,omitempty"`
-}
-
-type AudioTranscriptionResp struct {
-	Text     string  `json:"text"`
-	Duration float32 `json:"duration"`
-}
-
-func getBytes(req AudioTranscriptionReq) (*bytes.Reader, string, error) {
-	data := &bytes.Buffer{}
-	writer := multipart.NewWriter(data)
-	err := util.WriteFile(writer, "file", req.File)
-	if err != nil {
-		return nil, "", err
-	}
-	util.WriteField(writer, "model", req.Model)
-	util.WriteField(writer, "response_format", req.ResponseFormat)
-	if req.Prompt != nil {
-		util.WriteField(writer, "prompt", *req.Prompt)
-	}
-	if req.Language != nil {
-		util.WriteField(writer, "language", *req.Language)
-	}
-	if req.Temperature != nil {
-		util.WriteField(writer, "temperature", fmt.Sprintf("%f", *req.Temperature))
-	}
-	writer.Close()
-	return bytes.NewReader(data.Bytes()), writer.FormDataContentType(), nil
+	Audio       string  `json:"audio"`
+	Model       string  `json:"model"`
+	Prompt      string  `json:"prompt,omitempty"`
+	Temperature float32 `json:"temperature,omitempty"`
+	Language    string  `json:"language,omitempty"`
 }

ai/openai/v0/client.go

@@ -1,48 +1,21 @@
 package openai
 
 import (
-	"github.com/instill-ai/component/internal/util/httpclient"
 	"go.uber.org/zap"
 	"google.golang.org/protobuf/types/known/structpb"
-)
 
-func newClient(setup *structpb.Struct, logger *zap.Logger) *httpclient.Client {
-	c := httpclient.New("OpenAI", getBasePath(setup),
-		httpclient.WithLogger(logger),
-		httpclient.WithEndUserError(new(errBody)),
-	)
+	openaiclient "github.com/sashabaranov/go-openai"
+)
 
-	c.SetAuthToken(getAPIKey(setup))
+func newClient(setup *structpb.Struct, logger *zap.Logger) *openaiclient.Client {
 
+	cfg := openaiclient.DefaultConfig(getAPIKey(setup))
 	org := getOrg(setup)
 	if org != "" {
-		c.SetHeader("OpenAI-Organization", org)
+		cfg.OrgID = org
 	}
 
-	return c
-}
-
-type errBody struct {
-	Error struct {
-		Message string `json:"message"`
-	} `json:"error"`
-}
-
-func (e errBody) Message() string {
-	return e.Error.Message
-}
-
-// getBasePath returns OpenAI's API URL. This configuration param allows us to
-// override the API the connector will point to. It isn't meant to be exposed
-// to users. Rather, it can serve to test the logic against a fake server.
-// TODO instead of having the API value hardcoded in the codebase, it should be
-// read from a setup file or environment variable.
-func getBasePath(setup *structpb.Struct) string {
-	v, ok := setup.GetFields()["base-path"]
-	if !ok {
-		return host
-	}
-	return v.GetStringValue()
+	return openaiclient.NewClientWithConfig(cfg)
 }
 
 func getAPIKey(setup *structpb.Struct) string {