feat: manually mirror opencoze's code from bytedance

Change-Id: I09a73aadda978ad9511264a756b2ce51f5761adf

backend/infra/impl/document/parser/builtin/parse_image.go

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2025 coze-dev Authors
+ *
+ * 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.
+ */
+
+package builtin
+
+import (
+	"context"
+	"encoding/base64"
+	"fmt"
+	"io"
+
+	"github.com/cloudwego/eino/components/document/parser"
+	"github.com/cloudwego/eino/schema"
+
+	"github.com/coze-dev/coze-studio/backend/infra/contract/chatmodel"
+	contract "github.com/coze-dev/coze-studio/backend/infra/contract/document/parser"
+	"github.com/coze-dev/coze-studio/backend/pkg/errorx"
+	"github.com/coze-dev/coze-studio/backend/types/errno"
+)
+
+func parseImage(config *contract.Config, model chatmodel.BaseChatModel) parseFn {
+	return func(ctx context.Context, reader io.Reader, opts ...parser.Option) (docs []*schema.Document, err error) {
+		options := parser.GetCommonOptions(&parser.Options{}, opts...)
+		doc := &schema.Document{
+			MetaData: map[string]any{},
+		}
+		for k, v := range options.ExtraMeta {
+			doc.MetaData[k] = v
+		}
+
+		switch config.ParsingStrategy.ImageAnnotationType {
+		case contract.ImageAnnotationTypeModel:
+			if model == nil {
+				return nil, errorx.New(errno.ErrKnowledgeNonRetryableCode, errorx.KV("reason", "model is not provided"))
+			}
+
+			bytes, err := io.ReadAll(reader)
+			if err != nil {
+				return nil, err
+			}
+
+			b64 := base64.StdEncoding.EncodeToString(bytes)
+			mime := fmt.Sprintf("image/%s", config.FileExtension)
+			url := fmt.Sprintf("data:%s;base64,%s", mime, b64)
+
+			input := &schema.Message{
+				Role: schema.User,
+				MultiContent: []schema.ChatMessagePart{
+					{
+						Type: schema.ChatMessagePartTypeText,
+						//Text: "Give a short description of the image.", // TODO: prompt in current language
+						Text: "简短描述下这张图片",
+					},
+					{
+						Type: schema.ChatMessagePartTypeImageURL,
+						ImageURL: &schema.ChatMessageImageURL{
+							URL:      url,
+							MIMEType: mime,
+						},
+					},
+				},
+			}
+
+			output, err := model.Generate(ctx, []*schema.Message{input})
+			if err != nil {
+				return nil, fmt.Errorf("[parseImage] model generate failed: %w", err)
+			}
+
+			doc.Content = output.Content
+		case contract.ImageAnnotationTypeManual:
+			// do nothing
+		default:
+			return nil, fmt.Errorf("[parseImage] unknown image annotation type=%d", config.ParsingStrategy.ImageAnnotationType)
+		}
+
+		return []*schema.Document{doc}, nil
+	}
+}