I'm looking for a AngularJS-based way to prevent multiple submits per task.
I don't need buttons to be disabled after submission or close the form and wait for the task to be completed. Instead, I need requests to be unique.
To be more detailed, I need $http.get and $http.post stop sending multiple same requests.
Any Ideas?
According to this article, you can use provider decorator.
NOTE: this approach is based on angular-api
https://gist.github.com/adambuczynski/354364e2a58786e2be71
UPDATE
I've changed a little part in your suggested solution, because returned promises have lost .success and .error and .then.
Just use this edited code to have all of those functions working:
.config(["$provide", function ($provide) {
$provide.decorator('$http', function ($delegate, $q) {
var pendingRequests = {};
var $http = $delegate;
function hash(str) {
var h = 0;
var strlen = str.length;
if (strlen === 0) {
return h;
}
for (var i = 0, n; i < strlen; ++i) {
n = str.charCodeAt(i);
h = ((h << 5) - h) + n;
h = h & h;
}
return h >>> 0;
}
function getRequestIdentifier(config) {
var str = config.method + config.url;
if (config.data && typeof config.data === 'object') {
str += angular.toJson(config.data);
}
return hash(str);
}
var $duplicateRequestsFilter = function (config) {
if (config.ignoreDuplicateRequest) {
return $http(config);
}
var identifier = getRequestIdentifier(config);
if (pendingRequests[identifier]) {
if (config.rejectDuplicateRequest) {
return $q.reject({
data: '',
headers: {},
status: config.rejectDuplicateStatusCode || 400,
config: config
});
}
return pendingRequests[identifier];
}
pendingRequests[identifier] = $http(config);
$http(config).finally(function () {
delete pendingRequests[identifier];
});
return pendingRequests[identifier];
};
Object.keys($http).filter(function (key) {
return (typeof $http[key] === 'function');
}).forEach(function (key) {
$duplicateRequestsFilter[key] = $http[key];
});
return $duplicateRequestsFilter;
})
}])
It could be a performance issue but following idea could solve your problem.
Store the each request URL and DATA as key value pair on a variable. URL should be KEY. For Same URL multiple submission can be stored in a Array.
Then for any new call check the URL if it present in your stored object, then compare the data with each object thorughly (deep check, it is costly though). If any exact match found then stop the processing. As same request came. Other wise proceed and don't forget to store this data also.
But it is costly since need to check the data which could be havy.
Note: At the time of storing the data you could convert it to JSON String so it will be easier to compare between String.
here is the Code Algo
YourService.call(url, params) {
var Str1 = JSON.stringify(params);
if(StoredObj[url]) {
for each (StoredObj[url] as Str){
if(Str === Str1) {
return;
}
}
}
else {
StoredObj[url] = []; //new Array
}
StoredObj[url].push(Str1);
Call $http then;
}
