Cloud Code Dependent Async Operations

Question

Я не разбираюсь в JS, но должен написать некоторый Cloud Code.

У меня есть несколько операций httpRequest, возвращающих JSON, которые затем создают объекты Parse. После завершения всех этих операций я хочу запустить saveAll.

Вот укороченная версия функции для удобочитаемости. Есть *** указывающие на операцию асинхронной, которые должны быть зависим друг от друга:

Parse.Cloud.job("importPlaylists", function(request, status) { 


// Array to store new objects 
var playlistsToSave = []; 

// Iterate the countries (Sheets) 
for (var j = 0; j < urls.length; j++) { 

    // *** -- 1. HERE IS WHERE I LOOP THROUGH HTTPREQUESTS, GET JSON, AND CREATE A NUMBER OF PARSE OBJECTS 
    // Cloud function - http request 
    Parse.Cloud.httpRequest({ 
     url: url 
    }).then(function(httpResponse) { 

     // Parse response 
     var json = JSON.parse(httpResponse.buffer); 


     // Create playlist objects 
     for (var i = 0; i < json.feed.entry.length; i++) { 


     // Create Playlist objcts from json 
     var Playlist = Parse.Object.extend("Playlist"); 
     var playlist = new Playlist(); 
     // ... 

     // Add to caching array 
     playlistsToSave.push(playlist); 
     } 

    },function(httpResponse) { 
     // error 
     console.error('Request failed with response code ' + httpResponse.status); 

     status.error("Scheduled messages error: " + error); 
    }); 
} 

// *** -- 2. THIS IS THE SAVEALL OPERATION THAT NEEDS TO BE DEPENDENT ON ALL OF THOSE HTTPRESPONSES COMPLETING 
// Parse - Save objects 
Parse.Object.saveAll(playlistsToSave, { 
    success: function(saveList) { 
     status.success("Objects created successfully."); 
    }, 
    error: function(error) { 
     status.error("Unable to save objects."); 
    } 
    }); 

});

А вот полный код:

Parse.Cloud.job("importPlaylists", function(request, status) { 

// ID of the Google Spreadsheet 
var spreadsheetID = "someId"; 

// List of country codes and their Google Sheets Ids 
var territories = { 
    "us" : "od6", 
    "gb" : "olbnsti", 
    "it" : "oa6haa5", 
    "es" : "oxibv7k", 
    "fr" : "obisdv5", 
    "nl" : "ohrgz0b", 
    "de" : "ocqrxlj", 
    "pl" : "oi0umg5" 
} 

// Array to store new objects 
var playlistsToSave = []; 

// Iterate the countries (Sheets) 
for (var j = 0; j < territories.length; j++) { 

    var countryCode = territories[j]; 
    var sheetID = territories[countryCode]; 
    var url = "https://spreadsheets.google.com/feeds/list/" + spreadsheetID + "/" + sheetID + "/public/values?alt=json"; // Make sure it is public or set to Anyone with link can view 


    // *** - 1. This loops through each Google Sheet and creates Parse objects from the JSON 
    // Cloud function - http request 
    Parse.Cloud.httpRequest({ 
     url: url 
    }).then(function(httpResponse) { 

     // Parse response 
     var json = JSON.parse(httpResponse.buffer); 


     // Create playlist objects 
     for (var i = 0; i < json.feed.entry.length; i++) { 

     var each = json.feed.entry[i]; 

     // TODO: This needs error handling - if "gsx$" doesn't exist will crash 
     var name = each["gsx$name"]["$t"]; 
     var playlistid = each["gsx$playlistid"]["$t"]; 
     var description = each["gsx$description"]["$t"]; 
     var imageurl = each["gsx$imageurl"]["$t"]; 
     var categories = each["gsx$categories"]["$t"].split(','); // json returns a string from Sheet - split on commas 



     // Create Parse objects 
     var Playlist = Parse.Object.extend("Playlist"); 
     var playlist = new Playlist(); 
     playlist.set("name", name); 
     playlist.set("playlistId", playlistid); 
     playlist.set("description", description); 
     playlist.set("imageUrl", imageurl); 
     playlist.set("categories", categories); 
     playlist.add("territories", countryCode); 


     // Add to caching array 
     playlistsToSave.push(playlist);  
     } 

    },function(httpResponse) { 
     // error 
     console.error('Request failed with response code ' + httpResponse.status); 

     status.error("Scheduled messages error: " + error); 
    }); 
} 

// *** - 2. This is the saveAll operation that needs to be dependent on all the httpRequests completing 
// Parse - Save objects 
Parse.Object.saveAll(playlistsToSave, { 
    success: function(saveList) { 
     status.success("Objects created successfully."); 
    }, 
    error: function(error) { 
     status.error("Unable to save objects."); 
    } 
    }); 

}); 

Answer 1

Используйте этот async.js's each. Это позволит вам убедиться, что все httpRequests завершены.