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Showing posts from January, 2016

Handling Promises with $q in Angular JS

Old way of async operations [code lang="javascript"] function getCurrentUser(callback) $http.get("/api/users/me") .success(function(user){ callback(user); }); //Let assume if you have two functions as below getCurrentUser(function(user){ //function one //some task with user }); getPermissions(function(permission){ //function two //some task with permissions }); //If you need this both results simultaneously (Serialized) //you can use as below as for old method getCurrentUser(function(user){ getPermissions(function(permission){ //do what you want with users and permissions //But it contains following issues //[1] Not Parallelizable //[2] Not Composable //[3] Not Dynamic (have to define the structure at runtime) }); }); [/code] Better way if you go with Angular JS is service implementation. Its as below; [code lang="javascript"] //Then better way is $q //Service implemenation as below function getCurrentUser(){ //define deferred //this is one time use object