node.js - How can I release a resource in a nodeJS Q promise-chain and return a promise? -

new promises & q.

i call method abstracts underlying resource. method open resource processing close resource.

something this:

module.exports = function fetchrecords() {     return openconnection()         .then(fetchrecords)         .then(groupbyid)         .catch(rethrow)         .done(closeconnection); }   function closeconnection(result) {    releaseconnection();    return result; } 

since i'm calling done return not promise undefined.

i hoping in client do:

resource.fetchrecords().then(/*do else*/); 

it looks have expose underlying resource client can do:

resource   .openconnection()   .then(resource.fetchrecords)   .then(/*do else*/)   .catch(/*..*/)   .end(resource.close) 

i don't know q or promises...but thought maybe there better way?

should do:

 module.exports = function fetchrecords() {     return openconnection()         .then(fetchrecords)         .then(groupbyid)         .then(closeconnection)         .catch(rethrow); }  

instead of done use finally, returns promise:

https://github.com/kriskowal/q/wiki/api-reference#promisefinallycallback

module.exports = function fetchrecords() {     return openconnection()         .then(fetchrecords)         .then(groupbyid)         .catch(rethrow)         .finally(closeconnection); }