$.get error depending on result of php file - php

Question

I'm building a webpage where the user can 'sign' some agreements and view signed and new (unsigned) agreements. For this the webpage uses the 2 functions in the code below to get relevant information from the database and then build the webpage. Unfortenately, when -and only when- the php file (process.php) returns a variable nrofagreements=0, the console shows an error for the get function;for any other values nrofagreements>0 no error occurs - see the console log below. I also checked (with Netbeans debugger) that process.php works properly - see json output below for nrofagreements=0- but I still suspect that the error must be in this php file(?) Any idea what goes wrong and how to fix it?
A1. jquery code:
$(document).ready(function(){
function NewAgreements(){
var jqxhr = $.get( "process.php", //get all
{ command: "getnewagreements", val1: "", val2: "" },
function(msg) {
},
"json"
).done(function(msg) {
console.log( "NewAgreement. $.get result: second success" );
//some code here to build the form based on msg from $.get()
form = buildNewAgreementsform(msg); //build form with supplier agreements and related products
$("#wrapper").append(form);
})//.done(function()
.fail(function() {
console.log( "NewAgreement. $.get result: error" );
})//.fail(function()
.always(function() {
console.log( "NewAgreement. $.get result: finished" );
});//$.get(
}//function getX()
//used by: tabs-agreements
NewAgreements();
function SignedAgreements(){
var jqxhr = $.get( "process.php", //get all
{ command: "getsignedagreements", val1: "", val2: "" },
function(msg) {
//var ecorp_eprodselectid;
},
"json"
).done(function(msg) {
console.log( "SignedAgreement. $.get result: second success" );
//some code to build the form based on the msg info from $.get()
form = buildSignedAgreementsform(msg); //build form with supplier agreements and related products
$("#wrapper-signedagreements").append(form);
})//.done(function()
.fail(function() {
console.log( "SignedAgreement. $.get result: error" );
})//.fail(function()
.always(function() {
console.log( "SignedAgreement. $.get result: finished" );
});//$.get( ",
}
SignedAgreements();
}); //$(document).ready
A2 simplified php code:
session_start();
$response_array = array();
$cmd = $_GET['command'];
switch($cmd){ //command handler
case 'getsignedagreements':
//some code here
$response_array['nrofagreements'] = $k;
if($response_array['nrofagreements'] == 0){
$response_array['status_general'] = 'success';
break;
}
//some code here
break;
case 'getsignedagreements':
//some code here
break;
default: //invalid command from webpage
$response_array['status_general'] = 'error';
break;//default
}//switch
$str = json_encode($response_array);
echo json_encode($response_array);
B. log console:
NewAgreement. $.get result: error
NewAgreement. $.get result: finished
SignedAgreement. $.get result: second success
SignedAgreement. $.get result: finished
C log json output for function NewAgreements:
"{"nrofagreements":0,"status_general":"success"}"

Answer 1

I don't have a specific fix for you, but I've got something which will help point you in the right direction...
System Design
One of the philosophies we hold dear is the idea that everything needs to do its own job in the most efficient way. The problem for most developers is they get confused with what each part of their application will do, and consequently try & do 5 jobs with one component
The reason I'm explaining this is because part of your question asked whether you should validate with JS or PHP. The answer is that you have to know which part of the system will do -- it looks like you're using PHP to validate whether the input is valid with the session, so I would suggest that you only handle the logic for that in the PHP file
Ajax
Personally, I would handle the response in your $.get command, but I would change to Ajax as my own preference:
$.ajax({
url: "process.php",
data: { command: "getnewagreements", val1: "", val2: "" },
success: function (msg) {
//handle validation in here
},
error: function(msg) {
//only fires when the URL can't be found etc
}
});

Answer 2

I've tested your code, found one illogical item in process.php (one single case is handled):
//...
case 'getsignedagreements':
//...
//...
case 'getsignedagreements':
//...
==> should be corrected to something like (handling two cases):
//...
case 'getnewagreements':
//...
//...
case 'getsignedagreements':
//...