CODEWITHSUNDEEP
javascriptsqlazurescheduled-tasksazure-mobile-services
Libor Zapletal
Libor Zapletal

Reputation: 14102

Fill Azure Mobile Services from Scheduler

I created code like this for getting news from xml export from another website and I am trying to fill with it my database. 

function UpdateLunchTime() {
    var httpRequest = require('request');
    var xml2js = require('xml2js');
    var parser = new xml2js.Parser();
    var url = 'http://www...com/export/xml/actualities';
    httpRequest.get({
            url: url
    }, function(err, response, body) {
        if (err) {
            console.warn(statusCodes.INTERNAL_SERVER_ERROR, 
                'Some problem.');
        } else if (response.statusCode !== 200) {
            console.warn(statusCodes.BAD_REQUEST, 
                'Another problem');
        } else {
            //console.log(body);
            parser.parseString(body, function (err2, result) {
                //console.log(result.Root.event);
                var count = 0;
                for (var i=0;i<result.Root.event.length;i++)
                { 
                    //console.log(result.Root.event[i]);
                    InsertActionToDatabase(result.Root.event[i]);
                }
                /*
                result.Root.event.forEach(function(entry) {
                    InsertActionToDatabase(entry);
                });
                */
            });
        }
    });
}

function InsertActionToDatabase(action)
{
    var queryString = "INSERT INTO Action (title, description, ...) VALUES (?, ?, ...)";
    mssql.query(queryString, [action.akce[0], action.description[0],...], {
    success: function(insertResults) {
    },
      error: function(err) {
      console.log("Problem: " + err);
      }
    });
}

For individual actualities it's working fine but when I run it over whole xml I get this error:

Error: [Microsoft][SQL Server Native Client 10.0][SQL Server]Resource ID : 1. The request limit for the database is 180 and has been reached. See 'http://go.microsoft.com/fwlink/?LinkId=267637' for assistance.

And for a few last objects I get this error:

Error: [Microsoft][SQL Server Native Client 10.0]TCP Provider: Only one usage of each socket address (protocol/network address/port) is normally permitted.

Thanks for help

Upvotes: 1

Views: 103

Answers (1)

carlosfigueira
carlosfigueira

Reputation: 87308

The problem is that you're trying to make too many concurrent (insert) operations in your database. Remember that in node.js (almost) everything is asynchronous, so when you call InsertActionToDatabase for one of the items, this operation will start right away and not wait before it finishes to return. So you're basically trying to insert all of the events at once, and as the error message said there's a limit on the number of concurrent connections which can be made to the SQL server.

What you need to do is to change your loop to run asynchronously, by waiting for one of the operations to complete before starting the next one (you can also "batch" send a smaller number of operations at once, continuing after each batch is complete, but the code is a little more complicated) as shown below.

var count = result.Root.event.length;
var insertAction = function(index) {
    if (index >= count) return;
    InsertActionToDatabase(result.Root.event[i], function() {
        insertAction(index + 1);
    });
}
insertAction(0);

And the InsertActionToDatabase function would take a callback parameter to be called when it's done.

function InsertActionToDatabase(item, done) {
    var table = tables.getTable('event');
    table.insert(item, {
        success: function() {
            console.log('Inserted event: ', item);
            done();
        }
    });
}

Upvotes: 1

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