Question

I received a suggestion from a prior question that I need to amend my code chain a series of POST requests together, but I don’t have any idea how to accomplish this. Specifically, the advice I was given was to:

fire off a post, have its success handler fire off the next post,
etc… and then when all the posts are done, the final post’s success
handler fires off the get

This strategy makes sense to me but I do not know how to implement. I am trying to prevent the call to GET before all of the calls to POST have completed. Currently, I have implemented $.when.apply to delay the sending of GET. Here is the code for that:

function(){ 
$.when.apply(undefined, InsertTheAPPs()).done(function () {
$.ajax({
url: sURL + "fileappeal/send_apps_email",
success: function() {  
    var m = $.msg("my message",
    {header:'my header', live:10000});
    setTimeout(function(){
        if(m)m.setBody('...my other message.');             
    },3000);
    setTimeout(function(){
        if(m)m.close(function(){
              window.location.replace(sURL+'client/view');
        });
    },6000);
    $('#ajaxShield').fadeOut(1000);},
error: function(){
    $.msg("error message",
    {header:'error header', live:10000});
    }
}); 
}); 
}

Here is the code for the jQuery $.each loop. This is the code that needs to not only begin, but must end before the ajax call to fileappeal/send_apps_email above:

function InsertTheAPPs(){
$('input[name=c_maybe].c_box').each(function(){         
    var jqxhrs = [];
    if($(this).prop('checked')){ 
        var rn = $(this).prop('value'); 
        jqxhrs.push(
            $.ajax({
            url: sURL + 'fileappeal/insert_app',
            type:"POST",
            dataType: 'text',
            data: {'rn': rn},
            error: function(data) {console.log('Error:'+rn+'_'+data);}
            })
        )
    return jqxhrs;
    } 
}); 
}

Could someone demonstrate how I can modify the code above to implement the strategy of chaining together the multiple POST calls?

Answer 1

Don’t return from .each. It doesn’t work that way. Instead do this:

var jqxhrs = [];
$(...).each(...
});
return jqxhrs;

Nothing is assigned to the return value of .each, which you can’t get anyway. Returning from each allows it to be used like break/continue, which doesn’t make sense in your context.

Moreover, the var jqxhrs inside of the each loop causes a new variable to be declared in that context on each iteration of the loop.