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Reésolu ? : synchroniser des réponses asynchrones ???

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Le 16/04/2017 à 08:39, Une Bévue a écrit :
>
> est-ce possible en chaînant des "promises" ?

oui, j'ai simulé deux solutions avec des Promises :

solution promise.then(...)

         var albumsMethod = function() {
            var promise = new Promise(function(resolve, reject){
               setTimeout(function() {
                  data.albums = {delay: ((new Date()).getTime() - 
start), message: '« albumsMethod » completed'};
                  console_info('data:\n' + JSON.stringify(data, null, 2));
                  resolve(data);
               }, 500);
            });
            return promise;
         };

         var camerasMethod = function(someStuff) {
            var promise = new Promise(function(resolve, reject){
               setTimeout(function() {
                 data.cameras = {delay: ((new Date()).getTime() - 
start), message: '« camerasMethod » completed'};
                 console_info('data:\n' + JSON.stringify(data, null, 2));
                 resolve(data);
               }, 400);
            });
            return promise;
         };

         var locationsMethod = function(someStuff) {
            var promise = new Promise(function(resolve, reject){
               setTimeout(function() {
                 data.locations = {delay: ((new Date()).getTime() - 
start), message: '« locationsMethod » completed'};
                 console_info('data:\n' + JSON.stringify(data, null, 2));
                 resolve(data);
               }, 300);
            });
            return promise;
         };

         var personsMethod = function(someStuff) {
            var promise = new Promise(function(resolve, reject){
               setTimeout(function() {
                 data.persons = {delay: ((new Date()).getTime() - 
start), message: '« personsMethod » completed'};
                 console_info('data:\n' + JSON.stringify(data, null, 2));
                 resolve(data);
               }, 200);
            });
            return promise;
         };

 
albumsMethod().then(camerasMethod).then(locationsMethod).then(personsMethod);




solution Promise.all(...)
         var promises = [];
         var albumsPromise = new Promise(function(resolve, reject){
           setTimeout(function() {
             var albums = {delay: ((new Date()).getTime() - start), 
message: '« albumsPromise » resolved'};
             var albums_id = '9876543210';
             resolve({albums: albums, albums_id: albums_id});}, 1000);
         });
         promises.push(albumsPromise);

         var camerasPromise = new Promise(function(resolve, reject){
           setTimeout(function() {
             var cameras = {delay: ((new Date()).getTime() - start), 
message: '« camerasPromise » resolved'};
              resolve({cameras: cameras});}, 500);
         });
         promises.push(camerasPromise);

         var locationsPromise = new Promise(function(resolve, reject){
           setTimeout(function() {
             var locations = {delay: ((new Date()).getTime() - start), 
message: '« locationsPromise » resolved'};
             resolve({locations: locations});}, 1500);
         });
         promises.push(locationsPromise);

         var personsPromise = new Promise(function(resolve, reject){
           setTimeout(function() {
             var persons = {delay: ((new Date()).getTime() - start), 
message: '« personsPromise » resolved'};
             var persons_id = '0123456789';
             resolve({persons: persons, persons_id: persons_id});}, 100);
         });
         promises.push(personsPromise);

         Promise.all(promises).then(function(datas) {
           var data = {};
           for (var i = 0, l = datas.length; i < l; i++) {
             for (var prop in datas[i]) {
               data[prop] = datas[i][prop];
             }
           }
           console_info(((new Date()).getTime() - start) + ' - data:\n' 
+ JSON.stringify(data, null, 2));
         });

j'obtiens ce que je recherche :
1501 - data:
{
   "albums": {
     "delay": 1005,
     "message": "« albumsPromise » resolved"
   },
   "albums_id": "9876543210",
   "cameras": {
     "delay": 502,
     "message": "« camerasPromise » resolved"
   },
   "locations": {
     "delay": 1501,
     "message": "« locationsPromise » resolved"
   },
   "persons": {
     "delay": 104,
     "message": "« personsPromise » resolved"
   },
   "persons_id": "0123456789"
}


mais avec #all je dois "mettre à plat" l'array de résultats retournés.

testé sur websocket...

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synchroniser des réponses asynchrones ??? Une Bévue <unbewusst.sein@fai.invalid> - 2017-04-16 08:39 +0200
  Reésolu ? : synchroniser des réponses asynchrones ??? Une Bévue <unbewusst.sein@fai.invalid> - 2017-04-17 16:07 +0200

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