Code Merge MCP

Instructions

Implementation Reference

• src/tools/merge_content.js:28-196 (handler)

  Primary handler function executing the merge_content tool: processes directory or single file, filters binaries/gitignore, reads and merges file contents with separators, supports compression/caching/streams/memory monitoring, returns merged content and stats.

  /**
   * Handles the 'merge_content' MCP request.
   * @param {object} parameters Request parameters.
   * @param {string} parameters.path The target file or directory path.
   * @param {boolean} [parameters.compress=false] Whether to compress the output.
   * @param {boolean} [parameters.use_gitignore=true]
   * @param {boolean} [parameters.ignore_git=true]
   * @param {string[]} [parameters.custom_blacklist=[]]
   * @returns {Promise<object>} The result object containing the merged content string.
   */
  async function handleRequest(parameters) {
      console.error('merge_content: Starting execution');
      const startTime = Date.now();
  
      // 启动内存监控
      memoryMonitor.start(10000); // 每10秒检查一次
  
      const {
          path: targetPath,
          compress = false,
          use_gitignore,
          ignore_git,
          custom_blacklist,
          use_cache = true,
          use_streams = true,
          max_files = 1000 // 限制处理文件数量
      } = parameters;
  
      if (!targetPath) {
          memoryMonitor.stop();
          throw new Error("Missing required parameter: 'path'.");
      }
  
      // Resolve to absolute path
      const absolutePath = path.resolve(targetPath);
      console.error(`merge_content: Resolved path to ${absolutePath}`);
  
      let rootPath = absolutePath; // Assume path is directory initially
      let filesToProcess = [];
  
      // Validate path existence and determine if it's a file or directory
      try {
          const stats = await fs.stat(absolutePath);
          console.error(`merge_content: Path exists, checking type`);
  
          if (stats.isDirectory()) {
              // Path is a directory, list files within it
              console.error(`merge_content: Path is a directory, listing files`);
              rootPath = absolutePath; // Keep rootPath as the directory itself
  
              // For performance, default to false for gitignore to speed up processing
              filesToProcess = await listFiles(absolutePath, {
                  useGitignore: use_gitignore || false,
                  ignoreGit: ignore_git || true,
                  customBlacklist: custom_blacklist || []
              });
  
              // 限制文件数量以防止内存耗尽
              if (filesToProcess.length > max_files) {
                  console.error(`merge_content: Limiting files from ${filesToProcess.length} to ${max_files}`);
                  filesToProcess = filesToProcess.slice(0, max_files);
              }
  
              console.error(`merge_content: Found ${filesToProcess.length} files in directory`);
  
          } else if (stats.isFile()) {
              // Path is a single file
              console.error(`merge_content: Path is a file`);
              rootPath = path.dirname(absolutePath); // Set rootPath to the parent directory
              const relativeFilePath = path.basename(absolutePath);
  
              // Skip gitignore checks for single files to improve performance
              filesToProcess.push(relativeFilePath);
              console.error(`merge_content: Added single file to process: ${relativeFilePath}`);
  
              // Check if it's a binary file
              const fileExtension = path.extname(relativeFilePath).toLowerCase();
              if (BINARY_EXTENSIONS.has(fileExtension)) {
                  filesToProcess = []; // Clear if binary
                  console.error(`merge_content: Skipping binary file: ${relativeFilePath}`);
              }
          } else {
              // Path exists but is not a file or directory (e.g., socket, fifo)
              memoryMonitor.stop();
              throw new Error(`Path '${targetPath}' is not a file or directory.`);
          }
      } catch (error) {
          memoryMonitor.stop();
          if (error.code === 'ENOENT') {
              throw new Error(`Path '${targetPath}' not found.`);
          }
          throw new Error(`Error accessing path '${targetPath}': ${error.message}`);
      }
  
      if (filesToProcess.length === 0) {
          // If no files are left after filtering (or it was an ignored/binary single file)
          console.error(`merge_content: No files to process, returning empty content`);
          memoryMonitor.stop();
          return { merged_content: "" }; // Return empty content
      }
  
      // Read the content of the filtered files
      console.error(`merge_content: Reading content of ${filesToProcess.length} files`);
  
      // 使用优化的文件读取函数，支持缓存和流式处理
      const fileContentsMap = await readFiles(filesToProcess, rootPath, {
          useCache: use_cache,
          useStreams: use_streams,
          progressCallback: (progress) => {
              if (progress.percent % 10 === 0) { // 每完成10%输出一次进度
                  console.error(`merge_content: Reading progress ${progress.percent}% (${progress.completed}/${progress.total})`);
              }
          }
      });
  
      // Combine contents with headers, ensuring consistent order
      console.error(`merge_content: Combining file contents`);
      let combinedContent = "";
  
      // Sort file paths before merging for deterministic output
      const sortedRelativePaths = [...fileContentsMap.keys()].sort((a, b) => a.localeCompare(b));
      let filesProcessed = 0;
  
      sortedRelativePaths.forEach(relativeFilePath => {
          const content = fileContentsMap.get(relativeFilePath);
          if (content !== undefined) { // Check if file read was successful
              // Add a header to distinguish file contents
              const safeFilePath = relativeFilePath.replace(/\\/g, '/');
              combinedContent += `=== File Path: ${safeFilePath} ===\n\n`;
  
              // Process content to ensure it's safe for JSON serialization
              // We don't need to apply makeJsonSafe here as we're just building the combined content
              // The final result will be handled by the MCP server's adaptToolResult function
              combinedContent += content;
              combinedContent += '\n\n' + '='.repeat(50) + '\n\n';
              filesProcessed++;
          }
      });
  
      console.error(`merge_content: Successfully processed ${filesProcessed} files`);
  
      // Apply compression if requested
      let finalContent = combinedContent.trim(); // Trim final whitespace
      if (compress) {
          console.error(`merge_content: Compressing content`);
          finalContent = compressContent(finalContent);
      }
  
      // 获取内存使用情况
      const memoryUsage = memoryMonitor.getMemoryUsage();
      const executionTime = Date.now() - startTime;
  
      // 停止内存监控
      memoryMonitor.stop();
  
      console.error(`merge_content: Execution completed in ${executionTime}ms, memory used: ${memoryUsage.heapUsedMB}MB`);
  
      // 返回结果并包含性能指标
      return {
          merged_content: finalContent,
          performance: {
              executionTime,
              filesProcessed,
              totalFiles: filesToProcess.length,
              memoryUsedMB: memoryUsage.heapUsedMB,
              cacheStats: use_cache ? getFileCache().getStats() : null
          }
      };
  }

• src/tools/merge_content.js:28-37 (schema)

  JSDoc type definitions documenting input parameters and return type for the merge_content tool handler.

  /**
   * Handles the 'merge_content' MCP request.
   * @param {object} parameters Request parameters.
   * @param {string} parameters.path The target file or directory path.
   * @param {boolean} [parameters.compress=false] Whether to compress the output.
   * @param {boolean} [parameters.use_gitignore=true]
   * @param {boolean} [parameters.ignore_git=true]
   * @param {string[]} [parameters.custom_blacklist=[]]
   * @returns {Promise<object>} The result object containing the merged content string.
   */

• src/mcp-server.js:147-184 (registration)

  MCP server registration of the merge_content tool, including Zod input schema validation and wrapper async handler that calls the tool's handleRequest with logging and result adaptation.

  // Register the merge_content tool
  if (mergeContentHandler) {
      server.tool(
          'merge_content',
          'Merges content from multiple files into a single output file.',
          {
              path: z.string().describe('The target file or directory path.'),
              compress: z.boolean().optional().describe('Whether to compress the output.'),
              use_gitignore: z.boolean().optional().describe('Whether to use .gitignore rules.'),
              ignore_git: z.boolean().optional().describe('Whether to ignore the .git directory.'),
              custom_blacklist: z.array(z.string()).optional().describe('Custom blacklist items.'),
              use_cache: z.boolean().optional().describe('Whether to use file content cache.'),
              use_streams: z.boolean().optional().describe('Whether to use stream processing for large files.'),
              max_files: z.number().optional().describe('Maximum number of files to process.')
          },
          async (params) => {
              logInfo(`Executing merge_content tool with params: ${JSON.stringify(params)}`);
              try {
                  const startTime = Date.now();
                  const result = await mergeContentHandler(params);
                  const executionTime = Date.now() - startTime;
                  logDebug(`merge_content completed in ${executionTime}ms`);
  
                  // Ensure the merged content is safe for JSON serialization
                  if (result && result.merged_content) {
                      // We don't modify the content directly here
                      // The adaptToolResult function will handle the content safely
                      logDebug(`merge_content result size: ${result.merged_content.length} characters`);
                  }
  
                  return adaptToolResult(result);
              } catch (error) {
                  logError('Error in merge_content tool:', error);
                  throw error;
              }
          }
      );
  }

• src/mcp-server.js:63-85 (helper)

  Helper function adaptToolResult specifically handles formatting merge_content results into MCP 'content' array, including performance metrics display.

  // Handle merge_content result
  if (result.merged_content) {
      // Ensure merged content is safe for JSON serialization
      content.push({
          type: 'text',
          text: result.merged_content
      });
  
      // 如果有性能指标，添加到输出
      if (result.performance) {
          content.push({
              type: 'text',
              text: `\n\n--- Performance Metrics ---\n` +
                    `Execution time: ${result.performance.executionTime}ms\n` +
                    `Files processed: ${result.performance.filesProcessed}/${result.performance.totalFiles}\n` +
                    `Memory used: ${result.performance.memoryUsedMB}MB\n` +
                    (result.performance.cacheStats ?
                      `Cache hit rate: ${Math.round(result.performance.cacheStats.hitRate * 100)}%\n` +
                      `Cache size: ${result.performance.cacheStats.size} files (${result.performance.cacheStats.bytesStoredMB}MB)` :
                      `Cache: disabled`)
          });
      }
  }