I've read posts all over concerning this and I know it must be something silly, but I can't figure out why the following code is throwing "TypeError: listener must be a function"

Assume options

var server = https.createServer(options, function(request,response){
if (request.url==='/') request.url='/home/altronic/Opti-Cal/web/arimonitor.htm';
console.log("Request: " + request.url);
fs.readFile("public"+request.url,function(error,data){
    if (error) {
        response.writeHead(404, {"Content-type":"text/plain"});
        response.end ("Sorry the page you requested was not found.");
    } else {
        response.writeHead(200,{"Content-type":mime.lookup('public'+request.url)});
        response.end (data);

            }
})
}).listen(port);

Console output:

events.js:130
throw TypeError('listener must be a function');
      ^
TypeError: listener must be a function
at TypeError (<anonymous>)
at Server.EventEmitter.addListener (events.js:130:11)
at new Server (http.js:1816:10)
at Object.exports.createServer (http.js:1846:10)
at Object.<anonymous> (/home/altronic/Opti-Cal/src/Opti-Cal_HTTPS_Server.js:42:20)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)

Can anyone help me figure this out?

I've read posts all over concerning this and I know it must be something silly, but I can't figure out why the following code is throwing "TypeError: listener must be a function"

Assume options

var server = https.createServer(options, function(request,response){
if (request.url==='/') request.url='/home/altronic/Opti-Cal/web/arimonitor.htm';
console.log("Request: " + request.url);
fs.readFile("public"+request.url,function(error,data){
    if (error) {
        response.writeHead(404, {"Content-type":"text/plain"});
        response.end ("Sorry the page you requested was not found.");
    } else {
        response.writeHead(200,{"Content-type":mime.lookup('public'+request.url)});
        response.end (data);

            }
})
}).listen(port);

Console output:

events.js:130
throw TypeError('listener must be a function');
      ^
TypeError: listener must be a function
at TypeError (<anonymous>)
at Server.EventEmitter.addListener (events.js:130:11)
at new Server (http.js:1816:10)
at Object.exports.createServer (http.js:1846:10)
at Object.<anonymous> (/home/altronic/Opti-Cal/src/Opti-Cal_HTTPS_Server.js:42:20)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)

Can anyone help me figure this out?

• javascript
• node.js
• https

4 Answers 4

Where do you assign https? It looks like you’re probably requiring http, not https. http.createServer doesn’t accept options like https.createServer.

You may hit this error when using a node version < 9.6

See the docs and history. I was very confused that the docs said I could use an options object on http.createServer and got this error until I realized I hadn't updated node in a while.

https://nodejs.org/api/http.html#http_http_createserver_options_requestlistener

I had the same error message:

throw TypeError('listener must be a function');

I have two separate files server.js and handler.js. My problem was whilst I was requiring ( require(./handler.js) )my handler file in server.js I was not exporting it from handler.js file. You must have: module.exports =handler; at the bottom of your handler file

This is mostly coming from a version mismatch. Latest versions of nodejs's http.createServer() do take options in parameters like https does.