feat(artifact): adopt the advanced converting pipeline (#127)

Because 

our original converting pipeline is not versatile enough for some
complex documents.

This commit 

adopts the advanced pipeline using VLM.

pkg/service/pipeline.go

@@ -20,15 +20,13 @@ const chunkLength = 1024
 const chunkOverlap = 200
 const NamespaceID = "preset"
 
-// Note: this pipeline is for the old indexing pipeline
+// Note: this pipeline is for the old indexing pipeline having convert_result
 const ConvertDocToMDPipelineID = "indexing-convert-pdf"
 const DocToMDVersion = "v1.1.1"
 
-// TODO: we revert to the old pipeline. it will change to the new pipeline later.
-const ConvertDocToMDPipelineID2 = "indexing-convert-pdf"
-
-// TODO: we need to update the version after the new pipeline is ready
-const DocToMDVersion2 = "v1.1.1"
+// Note: this pipeline is for the new indexing pipeline having convert_result or convert_result2
+const ConvertDocToMDPipelineID2 = "indexing-advanced-convert-doc"
+const DocToMDVersion2 = "v1.2.0"
 
 const MdChunkPipelineID = "indexing-split-markdown"
 const MdSplitVersion = "v2.0.0"
@@ -144,8 +142,9 @@ func getFileTypePrefix(fileType artifactPb.FileType) string {
 	}
 }
 
-// Helper function to safely extract the "convert_result" from the response.
-// It checks if the index and key are available to avoid nil pointer issues.
+// getConvertResult extracts the conversion result from the pipeline response.
+// It first checks for a non-empty "convert_result" field, then falls back to "convert_result2".
+// Returns an error if neither field contains valid data or if the response structure is invalid.
 func getConvertResult(resp *pipelinePb.TriggerNamespacePipelineReleaseResponse) (string, error) {
 	if resp == nil || len(resp.Outputs) == 0 {
 		return "", fmt.Errorf("response is nil or has no outputs. resp: %v", resp)
@@ -155,10 +154,14 @@ func getConvertResult(resp *pipelinePb.TriggerNamespacePipelineReleaseResponse)
 		return "", fmt.Errorf("fields in the output are nil. resp: %v", resp)
 	}
 	convertResult, ok := fields["convert_result"]
-	if !ok {
-		return "", fmt.Errorf("convert_result not found in the output fields. resp: %v", resp)
+	if ok && convertResult.GetStringValue() != "" {
+		return convertResult.GetStringValue(), nil
 	}
-	return convertResult.GetStringValue(), nil
+	convertResult2, ok2 := fields["convert_result2"]
+	if ok2 && convertResult2.GetStringValue() != "" {
+		return convertResult2.GetStringValue(), nil
+	}
+	return "", fmt.Errorf("convert_result or convert_result2 not found in the output fields. resp: %v", resp)
 }
 
 type Chunk = struct {
@@ -365,7 +368,6 @@ func (s *Service) EmbeddingTextPipe(ctx context.Context, caller uuid.UUID, reque
 		batch := texts[i:end]
 		batchIndex := i / maxBatchSize
 
-
 		// Acquire semaphore before starting goroutine
 		sem <- struct{}{}
 		wg.Add(1)

pkg/worker/worker.go

@@ -490,11 +490,37 @@ func (wp *fileToEmbWorkerPool) processConvertingFile(ctx context.Context, file r
 	return updatedFile, artifactpb.FileProcessStatus_FILE_PROCESS_STATUS_CHUNKING, nil
 }
 
-// Processes a file with the status "chunking".
-// If the file is a PDF or other document type, it retrieves the converted file from MinIO and calls the markdown chunking pipeline.
-// If the file is a text or markdown file, it retrieves the file from MinIO and calls the respective chunking pipeline.
-// The resulting chunks are saved into object storage and metadata is updated in the database.
-// Finally, the file status is updated to "embedding" in the database.
+// Processes a file with the status "chunking" by splitting it into text chunks.
+// The processing varies by file type:
+//
+// For PDF, DOC, DOCX, PPT, PPTX, HTML, XLSX, XLS, CSV:
+// - Retrieves converted file from MinIO
+// - For spreadsheet files (XLSX, XLS, CSV): Uses markdown chunking pipeline
+// - For other document types: Uses text chunking pipeline
+//
+// For TEXT files:
+// - Retrieves original file from MinIO
+// - Uses text chunking pipeline
+//
+// For MARKDOWN files:
+// - Retrieves original file from MinIO
+// - Uses markdown chunking pipeline
+//
+// For all file types:
+// - Saves chunks to object storage
+// - Updates metadata in database with chunking pipeline info
+// - Updates file status to "embedding"
+//
+// Parameters:
+//   - ctx: Context for the operation
+//   - file: KnowledgeBaseFile struct containing file metadata
+//
+// Returns:
+//   - updatedFile: Updated KnowledgeBaseFile after processing
+//   - nextStatus: Next file process status (EMBEDDING if successful)
+//   - err: Error if any step fails
+//
+// The function handles errors at each step and returns appropriate status codes.
 func (wp *fileToEmbWorkerPool) processChunkingFile(ctx context.Context, file repository.KnowledgeBaseFile) (*repository.KnowledgeBaseFile, artifactpb.FileProcessStatus, error) {
 	logger, _ := logger.GetZapLogger(ctx)
 	logger.Info("Processing chunking status file.", zap.String("File uid", file.UID.String()))
@@ -527,10 +553,23 @@ func (wp *fileToEmbWorkerPool) processChunkingFile(ctx context.Context, file rep
 			return nil, artifactpb.FileProcessStatus_FILE_PROCESS_STATUS_UNSPECIFIED, err
 		}
 
-		// TODO: some file use splitTextPipe and some use splitMarkdownPipe
 		// call the markdown chunking pipeline
-		requesterUID := file.RequesterUID
-		chunks, err := wp.svc.SplitMarkdownPipe(ctx, file.CreatorUID, requesterUID, string(convertedFileData))
+		chunks := []service.Chunk{}
+		switch file.Type {
+		case artifactpb.FileType_FILE_TYPE_XLSX.String(),
+			artifactpb.FileType_FILE_TYPE_XLS.String(),
+			artifactpb.FileType_FILE_TYPE_CSV.String():
+			requesterUID := file.RequesterUID
+			chunks, err = wp.svc.SplitMarkdownPipe(ctx, file.CreatorUID, requesterUID, string(convertedFileData))
+		case artifactpb.FileType_FILE_TYPE_PDF.String(),
+			artifactpb.FileType_FILE_TYPE_DOCX.String(),
+			artifactpb.FileType_FILE_TYPE_DOC.String(),
+			artifactpb.FileType_FILE_TYPE_PPTX.String(),
+			artifactpb.FileType_FILE_TYPE_PPT.String(),
+			artifactpb.FileType_FILE_TYPE_HTML.String():
+			requesterUID := file.RequesterUID
+			chunks, err = wp.svc.SplitTextPipe(ctx, file.CreatorUID, requesterUID, string(convertedFileData))
+		}
 		if err != nil {
 			logger.Error("Failed to get chunks from converted file using markdown chunking pipeline.", zap.String("Converted file uid", convertedFile.UID.String()))
 			return nil, artifactpb.FileProcessStatus_FILE_PROCESS_STATUS_UNSPECIFIED, err