Guilherme C. Souza•3y ago

Am I closing this server wrongly? The port is not free for a new listener! (`AddrInUse`)

const server = Deno.listen({ port: 80 });

(async function(){

    for await(const conn of server){

        (async function(){
   
            const httpConn = Deno.serveHttp(conn);

            for await(const reqEvent of httpConn){
   
                reqEvent.respondWith(new Response('res.stream', {
                    status: 200
                }));

            }

        })();

    }

})();

const res = await fetch('http://localhost');
res.body?.cancel()
server.close();

// Port 80 is still in use here??

const newServer = Deno.listen({ port: 80 });
newServer.close();

const server = Deno.listen({ port: 80 });

(async function(){

    for await(const conn of server){

        (async function(){
   
            const httpConn = Deno.serveHttp(conn);

            for await(const reqEvent of httpConn){
   
                reqEvent.respondWith(new Response('res.stream', {
                    status: 200
                }));

            }

        })();

    }

})();

const res = await fetch('http://localhost');
res.body?.cancel()
server.close();

// Port 80 is still in use here??

const newServer = Deno.listen({ port: 80 });
newServer.close();

3 Replies

Doctor 🤖•3y ago

Looking at the docs I'd guess so, but it probably needs to sleep for a second for stuff outside of javascript to release it. Try doing await new Promise(a => setTimeout(_ => a(true), 0)) just after the server.close()

Guilherme C. SouzaOP•3y ago

It does help. Shouldn't Deno take care of it internally? Hopefully with some Promise I can wait on to make sure the port is released? This does work as expected in Node. Meaning I can bring a new server up once the close event is fired in the old one.

Doctor 🤖•3y ago

Idk. I’m guessing Deno releases it on its end and the OS just needs a bit of time to validate it or whatever. If sleeping for 0ms worked then you could wrap that Deno close in a promise.

await new Promise(a => {
    server.close()
    setTimeout(_ => a(true), 0)
})

await new Promise(a => {
    server.close()
    setTimeout(_ => a(true), 0)
})