Question

我对节点有点新意。我正在使用express和sendgrid api发送电子邮件（完全收集REST）。在sendgrid成功或失败后，我想用json对象进行响应。以下是示例案例：

var SendGrid = require('sendgrid-nodejs').SendGrid;
var sendgrid = new SendGrid(user, key);

app.get('/LGP/:email', function (req, res){
    sendgrid.send({
        to: req.params.email,
        from: 'me@example.com',
        subject: 'Hello World',
        text: 'This email sent through SendGrid'
        }, function(success, message) {
            if (!success) {
                console.log(message);
            } else {
                res.writeHead(200, { 'Content-Type': 'application/json' });
                res.write(JSON.stringify({ result: 'success' }));
                res.end(); //error occurs: "Can't use mutable header APIs after sent."
            }
        }
    );
});

在我的本地服务器上（使用工头），一切正常。但是当我把它推到heroku时，它给了我这个堆栈跟踪：

2013-02-27T22:12:46+00:00 app[web.1]: http.js:543
2013-02-27T22:12:46+00:00 app[web.1]:     throw new Error("Can't use mutable header APIs after sent.");
2013-02-27T22:12:46+00:00 app[web.1]:           ^
2013-02-27T22:12:46+00:00 app[web.1]: Error: Can't use mutable header APIs after sent.
2013-02-27T22:12:46+00:00 app[web.1]:     at ServerResponse.getHeader (http.js:543:11)
2013-02-27T22:12:46+00:00 app[web.1]:     at /app/node_modules/express/node_modules/connect/lib/middleware/logger.js:229:26
2013-02-27T22:12:46+00:00 app[web.1]:     at ServerResponse.<anonymous> (/app/node_modules/express/node_modules/connect/lib/middleware/logger.js:149:20)
2013-02-27T22:12:46+00:00 app[web.1]:     at /app/app.js:60:13
2013-02-27T22:12:46+00:00 app[web.1]:     at IncomingMessage.<anonymous> (/app/node_modules/sendgrid/lib/sendgrid.js:74:9)
2013-02-27T22:12:46+00:00 app[web.1]:     at IncomingMessage.emit (events.js:81:20)
2013-02-27T22:12:46+00:00 app[web.1]:     at HTTPParser.onMessageComplete (http.js:133:23)
2013-02-27T22:12:46+00:00 app[web.1]:     at CleartextStream.ondata (http.js:1213:22)
2013-02-27T22:12:46+00:00 app[web.1]:     at CleartextStream._push (tls.js:291:27)
2013-02-27T22:12:46+00:00 app[web.1]:     at SecurePair._cycle (tls.js:565:20)
2013-02-27T22:12:48+00:00 heroku[web.1]: Process exited with status 1
2013-02-27T22:12:48+00:00 heroku[web.1]: State changed from up to crashed

/app/app.js:60:13是指带有“res.end（）”的行。我做错了什么？

Answer 1

为了最大限度地提高您的应用在本地和heroku上运行的机会，您应该确保为所有模块指定特定版本，并避免使用"*"作为主dependencies。

还应该在package.json中指定节点版本：

"engines": {
  "node": "0.8.20"
}

（使用适合的任何版本）。

res.end上的Node.js和Sendgrid邮件程序错误

1 个答案: