Add Image generation API (#48)

image.go

@@ -0,0 +1,60 @@
+package gogpt
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+)
+
+// Image sizes defined by the OpenAI API.
+const (
+	CreateImageSize256x256   = "256x256"
+	CreateImageSize512x512   = "512x512"
+	CreateImageSize1024x1024 = "1024x1024"
+)
+
+const (
+	CreateImageResponseFormatURL     = "url"
+	CreateImageResponseFormatB64JSON = "b64_json"
+)
+
+// ImageRequest represents the request structure for the image API.
+type ImageRequest struct {
+	Prompt         string `json:"prompt,omitempty"`
+	N              int    `json:"n,omitempty"`
+	Size           string `json:"size,omitempty"`
+	ResponseFormat string `json:"response_format,omitempty"`
+	User           string `json:"user,omitempty"`
+}
+
+// ImageResponse represents a response structure for image API.
+type ImageResponse struct {
+	Created uint64                   `json:"created,omitempty"`
+	Data    []ImageResponseDataInner `json:"data,omitempty"`
+}
+
+// ImageResponseData represents a response data structure for image API.
+type ImageResponseDataInner struct {
+	URL     string `json:"url,omitempty"`
+	B64JSON string `json:"b64_json,omitempty"`
+}
+
+// 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 = json.Marshal(request)
+	if err != nil {
+		return
+	}
+
+	urlSuffix := "/images/generations"
+	req, err := http.NewRequest(http.MethodPost, c.fullURL(urlSuffix), bytes.NewBuffer(reqBytes))
+	if err != nil {
+		return
+	}
+
+	req = req.WithContext(ctx)
+	err = c.sendRequest(req, &response)
+	return
+}