NickName:Aamer Rasheed Ask DateTime:2018-11-12T15:17:44

how to create custom object/array using twilio fetch conference function in Node.js

I have been trying to generate custom object array or JSON object to fetch specific fields of conferences object that Twilio fetch conference API provides. But since Node.js is async so unable to achieve that and gets undefined in return as their is call back in each function. Tried various approaches but unable to get the result as due to operation nature of node.js call back is registered and next statement is executed. Tried various options of promises and async-await as well. However, unable to achieve a result which might be a call back within each loop (my guess).

Since new to Node.Js so need some suggestion how to achieve. One option is to use settimeout but again this is not a genuine solution as in case of a system in production unable to get information on how much time required. Code is given below:

exports.fetchLiveConferences = function(req, res, next) {
    let conferencesArray = [];

    client.conferences.each({
        dateCreated: new Date(),
        status: 'In-progress'
    }, conferences => {
        /* call back function at this point conferences object is available and can extract properties so pushing it to my array.
         */
        conferencesArray.push({
            conferenceSid: conferences.sid,
            conferenceName: conferences.friendlyName,
            conferenceStatus: conferences.status,
        });
    })

    console.log(conferencesArray);
    /* due to async nature the below statement is executed once call back is registered by node.js in event loop and undefined is returned. 
     */
    res.send(conferencesArray);
}

Copyright Notice：Content Author:「Aamer Rasheed」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/53257435/how-to-create-custom-object-array-using-twilio-fetch-conference-function-in-node

Answers

philnash 2018-11-13T02:38:59

Twilio developer evangelist here.\n\nYour issue here is that you are using each to list the conferences independently. If you just want to work with the list, then you should use the list method and then return the results in the callback.\n\nTry something like this.\n\nexports.fetchLiveConferences = function(req, res, next) {\n client.conferences.list({\n dateCreated: new Date(),\n status: 'In-progress'\n }, (err, conferences) => {\n if (err) { console.error(err); return; }\n conferencesArray = conferences.map(conference => ({\n conferenceSid: conference.sid,\n conferenceName: conference.friendlyName,\n conferenceStatus: conference.status,\n }));\n res.send(conferencesArray);\n })\n}\n\n\nIn this case the conferences onject in the callback is a list of conferences. You can then map over the conferences and build the objects that you want, returning them as the response.\n\nUpdate\n\nIf you want to uses promises and async and await the list method also returns a promise. You can use it like this.\n\nconst fetchConferenceList = () => {\n return client.conferences.list({\n dateCreated: new Date(),\n status: 'In-progress'\n }).then(conferences => conferences.map(conference => ({\n conferenceSid: conference.sid,\n conferenceName: conference.friendlyName,\n conferenceStatus: conference.status,\n })));\n}\n\nexports.fetchLiveConferences = async function(req, res, next) {\n const conferenceData = await fetchConferenceList();\n res.send(conferenceData);\n}\n",

R.A. Lucas 2018-11-12T08:14:53

You should just be able to put your res.send function inside the callback like such:\n\nclient.conferences.each({\n dateCreated: new Date(),\n status: 'In-progress'\n}, conferences => {\n /* call back function at this point conferences object is available and can extract properties so pushing it to my array.\n */\n conferencesArray = conferences.map(c => {\n return {\n conferenceSid: c.sid,\n conferenceName: c.friendlyName,\n conferenceStatus: c.status,\n }\n });\n res.send(conferencesArray);\n})\n",