Add testable request builder (#162)

* Add testable request builder

* improve tests

api.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -12,7 +11,7 @@ import (
 type Client struct {
 	config ClientConfig
 
-	marshaller marshaller
+	requestBuilder requestBuilder
 }
 
 // NewClient creates new OpenAI API client.
@@ -24,8 +23,8 @@ func NewClient(authToken string) *Client {
 // NewClientWithConfig creates new OpenAI API client for specified config.
 func NewClientWithConfig(config ClientConfig) *Client {
 	return &Client{
-		config:     config,
+		config:         config,
-		marshaller: &jsonMarshaller{},
+		requestBuilder: newRequestBuilder(),
 	}
 }
 
@@ -91,17 +90,8 @@ func (c *Client) newStreamRequest(
 	ctx context.Context,
 	method string,
 	urlSuffix string,
-	body interface{}) (*http.Request, error) {
+	body any) (*http.Request, error) {
-	var reqBody []byte
+	req, err := c.requestBuilder.build(ctx, method, c.fullURL(urlSuffix), body)
-	if body != nil {
-		var err error
-		reqBody, err = c.marshaller.marshal(body)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	req, err := http.NewRequestWithContext(ctx, method, c.fullURL(urlSuffix), bytes.NewBuffer(reqBody))
 	if err != nil {
 		return nil, err
 	}

chat.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"errors"
 	"net/http"
@@ -72,14 +71,8 @@ func (c *Client) CreateChatCompletion(
 		return
 	}
 
-	var reqBytes []byte
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
 	urlSuffix := "/chat/completions"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL(urlSuffix), request)
 	if err != nil {
 		return
 	}

completion.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"errors"
 	"net/http"
@@ -105,14 +104,8 @@ func (c *Client) CreateCompletion(
 		return
 	}
 
-	var reqBytes []byte
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
 	urlSuffix := "/completions"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL(urlSuffix), request)
 	if err != nil {
 		return
 	}

edits.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"net/http"
 )
@@ -32,13 +31,7 @@ type EditsResponse struct {
 
 // Perform an API call to the Edits endpoint.
 func (c *Client) Edits(ctx context.Context, request EditsRequest) (response EditsResponse, err error) {
-	var reqBytes []byte
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL("/edits"), request)
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL("/edits"), bytes.NewBuffer(reqBytes))
 	if err != nil {
 		return
 	}

embeddings.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"net/http"
 )
@@ -133,14 +132,7 @@ type EmbeddingRequest struct {
 // CreateEmbeddings returns an EmbeddingResponse which will contain an Embedding for every item in |request.Input|.
 // https://beta.openai.com/docs/api-reference/embeddings/create
 func (c *Client) CreateEmbeddings(ctx context.Context, request EmbeddingRequest) (resp EmbeddingResponse, err error) {
-	var reqBytes []byte
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL("/embeddings"), request)
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
-	urlSuffix := "/embeddings"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
 	if err != nil {
 		return
 	}

engines.go

@@ -22,7 +22,7 @@ type EnginesList struct {
 // ListEngines Lists the currently available engines, and provides basic
 // information about each option such as the owner and availability.
 func (c *Client) ListEngines(ctx context.Context) (engines EnginesList, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL("/engines"), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL("/engines"), nil)
 	if err != nil {
 		return
 	}
@@ -38,7 +38,7 @@ func (c *Client) GetEngine(
 	engineID string,
 ) (engine Engine, err error) {
 	urlSuffix := fmt.Sprintf("/engines/%s", engineID)
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
 	if err != nil {
 		return
 	}

files.go

@@ -112,7 +112,7 @@ func (c *Client) CreateFile(ctx context.Context, request FileRequest) (file File
 
 // DeleteFile deletes an existing file.
 func (c *Client) DeleteFile(ctx context.Context, fileID string) (err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodDelete, c.fullURL("/files/"+fileID), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodDelete, c.fullURL("/files/"+fileID), nil)
 	if err != nil {
 		return
 	}
@@ -124,7 +124,7 @@ func (c *Client) DeleteFile(ctx context.Context, fileID string) (err error) {
 // ListFiles Lists the currently available files,
 // and provides basic information about each file such as the file name and purpose.
 func (c *Client) ListFiles(ctx context.Context) (files FilesList, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL("/files"), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL("/files"), nil)
 	if err != nil {
 		return
 	}
@@ -137,7 +137,7 @@ func (c *Client) ListFiles(ctx context.Context) (files FilesList, err error) {
 // such as the file name and purpose.
 func (c *Client) GetFile(ctx context.Context, fileID string) (file File, err error) {
 	urlSuffix := fmt.Sprintf("/files/%s", fileID)
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
 	if err != nil {
 		return
 	}

fine_tunes.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"net/http"
@@ -68,14 +67,8 @@ type FineTuneDeleteResponse struct {
 }
 
 func (c *Client) CreateFineTune(ctx context.Context, request FineTuneRequest) (response FineTune, err error) {
-	var reqBytes []byte
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
 	urlSuffix := "/fine-tunes"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL(urlSuffix), request)
 	if err != nil {
 		return
 	}
@@ -86,7 +79,7 @@ func (c *Client) CreateFineTune(ctx context.Context, request FineTuneRequest) (r
 
 // CancelFineTune cancel a fine-tune job.
 func (c *Client) CancelFineTune(ctx context.Context, fineTuneID string) (response FineTune, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL("/fine-tunes/"+fineTuneID+"/cancel"), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL("/fine-tunes/"+fineTuneID+"/cancel"), nil)
 	if err != nil {
 		return
 	}
@@ -96,7 +89,7 @@ func (c *Client) CancelFineTune(ctx context.Context, fineTuneID string) (respons
 }
 
 func (c *Client) ListFineTunes(ctx context.Context) (response FineTuneList, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL("/fine-tunes"), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL("/fine-tunes"), nil)
 	if err != nil {
 		return
 	}
@@ -107,7 +100,7 @@ func (c *Client) ListFineTunes(ctx context.Context) (response FineTuneList, err
 
 func (c *Client) GetFineTune(ctx context.Context, fineTuneID string) (response FineTune, err error) {
 	urlSuffix := fmt.Sprintf("/fine-tunes/%s", fineTuneID)
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL(urlSuffix), nil)
 	if err != nil {
 		return
 	}
@@ -117,7 +110,7 @@ func (c *Client) GetFineTune(ctx context.Context, fineTuneID string) (response F
 }
 
 func (c *Client) DeleteFineTune(ctx context.Context, fineTuneID string) (response FineTuneDeleteResponse, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodDelete, c.fullURL("/fine-tunes/"+fineTuneID), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodDelete, c.fullURL("/fine-tunes/"+fineTuneID), nil)
 	if err != nil {
 		return
 	}
@@ -127,7 +120,7 @@ func (c *Client) DeleteFineTune(ctx context.Context, fineTuneID string) (respons
 }
 
 func (c *Client) ListFineTuneEvents(ctx context.Context, fineTuneID string) (response FineTuneEventList, err error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.fullURL("/fine-tunes/"+fineTuneID+"/events"), nil)
+	req, err := c.requestBuilder.build(ctx, http.MethodGet, c.fullURL("/fine-tunes/"+fineTuneID+"/events"), nil)
 	if err != nil {
 		return
 	}

image.go

@@ -45,14 +45,8 @@ type ImageResponseDataInner struct {
 
 // CreateImage - API call to create an image. This is the main endpoint of the DALL-E API.
 func (c *Client) CreateImage(ctx context.Context, request ImageRequest) (response ImageResponse, err error) {
-	var reqBytes []byte
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
 	urlSuffix := "/images/generations"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL(urlSuffix), request)
 	if err != nil {
 		return
 	}

marshaller_test.go

@@ -1,71 +0,0 @@
-package openai //nolint:testpackage // testing private field
-
-import (
-	"github.com/sashabaranov/go-openai/internal/test"
-
-	"context"
-	"errors"
-	"testing"
-)
-
-type failingMarshaller struct{}
-
-var errTestMarshallerFailed = errors.New("test marshaller failed")
-
-func (jm *failingMarshaller) marshal(value any) ([]byte, error) {
-	return []byte{}, errTestMarshallerFailed
-}
-
-func TestClientReturnMarshallerErrors(t *testing.T) {
-	var err error
-	ts := test.NewTestServer().OpenAITestServer()
-	ts.Start()
-	defer ts.Close()
-
-	config := DefaultConfig(test.GetTestToken())
-	config.BaseURL = ts.URL + "/v1"
-	client := NewClientWithConfig(config)
-	client.marshaller = &failingMarshaller{}
-
-	ctx := context.Background()
-
-	_, err = client.CreateCompletion(ctx, CompletionRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.CreateChatCompletion(ctx, ChatCompletionRequest{Model: GPT3Dot5Turbo})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.CreateChatCompletionStream(ctx, ChatCompletionRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.CreateFineTune(ctx, FineTuneRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.Moderations(ctx, ModerationRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.Edits(ctx, EditsRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.CreateEmbeddings(ctx, EmbeddingRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-
-	_, err = client.CreateImage(ctx, ImageRequest{})
-	if !errors.Is(err, errTestMarshallerFailed) {
-		t.Fatalf("Did not return error when marshaller failed: %v", err)
-	}
-}

moderation.go

@@ -1,7 +1,6 @@
 package openai
 
 import (
-	"bytes"
 	"context"
 	"net/http"
 )
@@ -51,13 +50,7 @@ type ModerationResponse struct {
 // Moderations — perform a moderation api call over a string.
 // Input can be an array or slice but a string will reduce the complexity.
 func (c *Client) Moderations(ctx context.Context, request ModerationRequest) (response ModerationResponse, err error) {
-	var reqBytes []byte
+	req, err := c.requestBuilder.build(ctx, http.MethodPost, c.fullURL("/moderations"), request)
-	reqBytes, err = c.marshaller.marshal(request)
-	if err != nil {
-		return
-	}
-
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.fullURL("/moderations"), bytes.NewBuffer(reqBytes))
 	if err != nil {
 		return
 	}

request_builder.go

@@ -0,0 +1,40 @@
+package openai
+
+import (
+	"bytes"
+	"context"
+	"net/http"
+)
+
+type requestBuilder interface {
+	build(ctx context.Context, method, url string, request any) (*http.Request, error)
+}
+
+type httpRequestBuilder struct {
+	marshaller marshaller
+}
+
+func newRequestBuilder() *httpRequestBuilder {
+	return &httpRequestBuilder{
+		marshaller: &jsonMarshaller{},
+	}
+}
+
+func (b *httpRequestBuilder) build(ctx context.Context, method, url string, request any) (*http.Request, error) {
+	if request == nil {
+		return http.NewRequestWithContext(ctx, method, url, nil)
+	}
+
+	var reqBytes []byte
+	reqBytes, err := b.marshaller.marshal(request)
+	if err != nil {
+		return nil, err
+	}
+
+	return http.NewRequestWithContext(
+		ctx,
+		method,
+		url,
+		bytes.NewBuffer(reqBytes),
+	)
+}

request_builder_test.go

@@ -0,0 +1,143 @@
+package openai //nolint:testpackage // testing private field
+
+import (
+	"github.com/sashabaranov/go-openai/internal/test"
+
+	"context"
+	"errors"
+	"net/http"
+	"testing"
+)
+
+var (
+	errTestMarshallerFailed     = errors.New("test marshaller failed")
+	errTestRequestBuilderFailed = errors.New("test request builder failed")
+)
+
+type (
+	failingRequestBuilder struct{}
+	failingMarshaller     struct{}
+)
+
+func (*failingMarshaller) marshal(value any) ([]byte, error) {
+	return []byte{}, errTestMarshallerFailed
+}
+
+func (*failingRequestBuilder) build(ctx context.Context, method, url string, requset any) (*http.Request, error) {
+	return nil, errTestRequestBuilderFailed
+}
+
+func TestRequestBuilderReturnsMarshallerErrors(t *testing.T) {
+	builder := httpRequestBuilder{
+		marshaller: &failingMarshaller{},
+	}
+
+	_, err := builder.build(context.Background(), "", "", struct{}{})
+	if !errors.Is(err, errTestMarshallerFailed) {
+		t.Fatalf("Did not return error when marshaller failed: %v", err)
+	}
+}
+
+func TestClientReturnsRequestBuilderErrors(t *testing.T) {
+	var err error
+	ts := test.NewTestServer().OpenAITestServer()
+	ts.Start()
+	defer ts.Close()
+
+	config := DefaultConfig(test.GetTestToken())
+	config.BaseURL = ts.URL + "/v1"
+	client := NewClientWithConfig(config)
+	client.requestBuilder = &failingRequestBuilder{}
+
+	ctx := context.Background()
+
+	_, err = client.CreateCompletion(ctx, CompletionRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CreateChatCompletion(ctx, ChatCompletionRequest{Model: GPT3Dot5Turbo})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CreateChatCompletionStream(ctx, ChatCompletionRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CreateFineTune(ctx, FineTuneRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.ListFineTunes(ctx)
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CancelFineTune(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.GetFineTune(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.DeleteFineTune(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.ListFineTuneEvents(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.Moderations(ctx, ModerationRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.Edits(ctx, EditsRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CreateEmbeddings(ctx, EmbeddingRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.CreateImage(ctx, ImageRequest{})
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	err = client.DeleteFile(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.GetFile(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.ListFiles(ctx)
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.ListEngines(ctx)
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+
+	_, err = client.GetEngine(ctx, "")
+	if !errors.Is(err, errTestRequestBuilderFailed) {
+		t.Fatalf("Did not return error when request builder failed: %v", err)
+	}
+}