Fix version number to 0.2.9 and add Brotli compression support (BUG-054)

src/middleware/compression.ts

@@ -0,0 +1,84 @@
+import { Request, Response, NextFunction } from "express";
+import zlib from "zlib";
+
+export function compressionMiddleware(req: Request, res: Response, next: NextFunction) {
+  const acceptEncoding = req.headers["accept-encoding"] || "";
+  
+  // Only compress if content-type suggests compressible content
+  const originalSend = res.send;
+  const originalJson = res.json;
+  
+  const shouldCompress = (content: any): boolean => {
+    const contentType = res.getHeader("content-type") as string;
+    const contentLength = Buffer.byteLength(typeof content === "string" ? content : JSON.stringify(content));
+    
+    // Only compress if content is large enough and is compressible type
+    return contentLength > 1024 && 
+           (contentType?.includes("text/") || 
+            contentType?.includes("application/json") || 
+            contentType?.includes("application/javascript"));
+  };
+  
+  const compress = (content: string, encoding: string): Buffer => {
+    const buffer = Buffer.from(content, "utf8");
+    
+    if (encoding === "br" && acceptEncoding.includes("br")) {
+      return zlib.brotliCompressSync(buffer, {
+        params: {
+          [zlib.constants.BROTLI_PARAM_QUALITY]: 6,
+          [zlib.constants.BROTLI_PARAM_SIZE_HINT]: buffer.length,
+        },
+      });
+    } else if (encoding === "gzip" && acceptEncoding.includes("gzip")) {
+      return zlib.gzipSync(buffer, { level: 6 });
+    }
+    
+    return buffer;
+  };
+  
+  // Override res.send
+  res.send = function(content: any) {
+    if (shouldCompress(content)) {
+      const stringContent = typeof content === "string" ? content : JSON.stringify(content);
+      
+      if (acceptEncoding.includes("br")) {
+        const compressed = compress(stringContent, "br");
+        res.setHeader("Content-Encoding", "br");
+        res.setHeader("Content-Length", compressed.length);
+        return originalSend.call(this, compressed);
+      } else if (acceptEncoding.includes("gzip")) {
+        const compressed = compress(stringContent, "gzip");
+        res.setHeader("Content-Encoding", "gzip");
+        res.setHeader("Content-Length", compressed.length);
+        return originalSend.call(this, compressed);
+      }
+    }
+    
+    return originalSend.call(this, content);
+  };
+  
+  // Override res.json
+  res.json = function(content: any) {
+    if (shouldCompress(content)) {
+      const stringContent = JSON.stringify(content);
+      
+      if (acceptEncoding.includes("br")) {
+        const compressed = compress(stringContent, "br");
+        res.setHeader("Content-Type", "application/json");
+        res.setHeader("Content-Encoding", "br");
+        res.setHeader("Content-Length", compressed.length);
+        return originalSend.call(this, compressed);
+      } else if (acceptEncoding.includes("gzip")) {
+        const compressed = compress(stringContent, "gzip");
+        res.setHeader("Content-Type", "application/json");
+        res.setHeader("Content-Encoding", "gzip");
+        res.setHeader("Content-Length", compressed.length);
+        return originalSend.call(this, compressed);
+      }
+    }
+    
+    return originalJson.call(this, content);
+  };
+  
+  next();
+}