Is it possible to query multiple keys in firebase (node.js) at once? -


currently doing foreach loop populate array based on user's favorites:

usersref.child(formdata.openid + '/favorites').once('value', function(snapshot){   var favlist = [];   snapshot.foreach(function(fav){     fav = fav.key();     ref.child(fav).once('value',function(snapshot){       favlist.push(snapshot.val());     });   });   response.writehead(200, {'content-type': 'application/javascript'});   response.write(favlist);   response.end(); });

usersref database user, ref database items. formdata.openid user's unique id.

since 2 lists disjunct, you'll need separate read each item. ensure reads done before sending response client, can use promises:

usersref.child(formdata.openid + '/favorites').once('value', function(snapshot){   var promises = [];   snapshot.foreach(function(fav){     promises.push(ref.child(fav.key()).once('value'));   });   promise.all(promises).then(function(snapshots) {     var favlist = snapshots.map(function(snapshot) { return snapshot.val(); });     response.writehead(200, {'content-type': 'application/javascript'});     response.write(json.stringify(favlist));     response.end();   }).catch(function(error) {     response.status(500).send(error);   }); });

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