Update app.js

app.js

@@ -1,7 +1,10 @@
 const express = require('express');
 const fetch = require('node-fetch');
+const zlib = require('zlib');
+const stream = require('stream');
+const { promisify } = require('util');
 
-const MODEL = 'claude-3-5-sonnet@20240620';
+const pipeline = promisify(stream.pipeline);
 
 const PROJECT_ID = process.env.PROJECT_ID;
 const CLIENT_ID = process.env.CLIENT_ID;
@@ -17,7 +20,6 @@ let tokenCache = {
   refreshPromise: null
 };
 
-// 日志函数
 function logRequest(req, status, message) {
   const timestamp = new Date().toISOString();
   const method = req.method;
@@ -71,8 +73,15 @@ function getLocation() {
   return currentSeconds < 30 ? 'europe-west1' : 'us-east5';
 }
 
-function constructApiUrl(location) {
-  return `https://${location}-aiplatform.googleapis.com/v1/projects/${PROJECT_ID}/locations/${location}/publishers/anthropic/models/${MODEL}:streamRawPredict`;
+function constructApiUrl(location, model) {
+  return `https://${location}-aiplatform.googleapis.com/v1/projects/${PROJECT_ID}/locations/${location}/publishers/anthropic/models/${model}:streamRawPredict`;
+}
+
+function formatModelName(model) {
+  if (model === 'claude-3-5-sonnet-20240620') {
+    return 'claude-3-5-sonnet@20240620';
+  }
+  return model;
 }
 
 async function handleRequest(req, res) {
@@ -97,10 +106,14 @@ async function handleRequest(req, res) {
 
   const accessToken = await getAccessToken();
   const location = getLocation();
-  const apiUrl = constructApiUrl(location);
 
   let requestBody = req.body;
   
+  let model = requestBody.model || 'claude-3-5-sonnet@20240620';
+  model = formatModelName(model);
+  
+  const apiUrl = constructApiUrl(location, model);
+
   if (requestBody.anthropic_version) {
     delete requestBody.anthropic_version;
   }
@@ -116,21 +129,39 @@ async function handleRequest(req, res) {
       method: 'POST',
       headers: {
         'Authorization': `Bearer ${accessToken}`,
-        'Content-Type': 'application/json; charset=utf-8'
+        'Content-Type': 'application/json; charset=utf-8',
+        'Accept-Encoding': 'gzip, deflate'
       },
       body: JSON.stringify(requestBody)
     });
 
     res.status(response.status);
-    response.headers.forEach((value, name) => {
-      res.setHeader(name, value);
-    });
+    
+    for (const [key, value] of response.headers.entries()) {
+      if (key.toLowerCase() !== 'content-encoding' && key.toLowerCase() !== 'content-length') {
+        res.setHeader(key, value);
+      }
+    }
+
     res.setHeader('Access-Control-Allow-Origin', '*');
     res.setHeader('Access-Control-Allow-Methods', 'POST, GET, OPTIONS');
     res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization, x-api-key, anthropic-version, model');
 
-    logRequest(req, response.status, 'Request forwarded successfully');
-    response.body.pipe(res);
+    const contentEncoding = response.headers.get('content-encoding');
+    if (contentEncoding === 'gzip') {
+      await pipeline(
+        response.body,
+        zlib.createGunzip(),
+        res
+      );
+    } else {
+      await pipeline(
+        response.body,
+        res
+      );
+    }
+
+    logRequest(req, response.status, `Request forwarded successfully for model: ${model}`);
   } catch (error) {
     console.error('Error:', error);
     res.status(500).json({