How to clean xml request before sending to web service - php

Question

Good day i am trying to send an xml to a web service but would need to clean the xml before sending. So far I have tried different ways and now been stuck for a while.
I capture the data from a form and post it to my php file to process. If the user doesnt enter any data in the length/width/height then i would like to clean my xml and remove empty element so it can pass validation on the server where sending xml request too.
Here below is a snippet of the data cpatured from my post and build the xml file accordingly but what if the dimensions were omitted? Could I also clean other elements that are empty?
$xmlRequest = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<mailing-scenario xmlns="http://www.mysite.com/ws/ship/rate-v2">
<customer-number>{$mailedBy}</customer-number>
<parcel-characteristics>
<weight>{$weight}</weight>
<dimensions>
<length>{$length}</length>
<width>{$width}</width>
<height>{$height}</height>
</dimensions>
</parcel-characteristics>
<origin-postal-code>{$originPostalCode}</origin-postal-code>
<destination>
<domestic>
<postal-code>{$postalCode}</postal-code>
</domestic>
</destination>
</mailing-scenario>
XML;
$xmlRequest = phpquery::newDocument();
$xp = new DOMXPath($xmlRequest->getDOMDocument());
foreach($xp->query('//*[not(node()) or normalize-space() = ""]') as $node) {
$node->parentNode->removeChild($node);
}

Answer 1

Okay here an example with just simple dom. Maybe some points first, you'll have decide what to do if no customer number is given or a negative weight, ... .
So you have to clean the XML but sometimes cleaning it will make either the request invalid or the user might get some result he did not expect. For instance he might put 1kg as weight you remove the kg because the weight is set in g and a string there is just wrong. If you don't tell the user he might yell at you!
And also just because all nodes are valid does not mean the request is correct, as there might be some missing nodes, so you also have to check for the requirements!
One last word to efficency, if you can get all these fields from the user without XML because the user just sends one parcel at a time. Do it like that and just check if that data is correct.
If you have to use XML, put still just send one package at a time you can just fetch the data check the validity and reconstruct the validated XML.
I would just use this example if I know that these XML requests might be really extensive and/or have a complex format.
function cleanXML($data){
// ok the data is string! So get your node.
$node = simplexml_load_string($data);
// now we can iterate throught all child nodes:
foreach($node->children() as $child){
//so here we got the childrens
// All child nodes of the root should be mailing scenarios
if($child->getName() == "mailing-scenario"){
//otherwise we check if mailing scenario is valid
if(!validateMScenario($child)){
//This node seems not so valid
//you have to decide what to do now!
}
}
else{
//Here we remove all nodes that are different
unset($child[0]);
echo "Error: Needed to remove Node";
}
}
// Just give them their cleaned XML!
return $node->asXML();
}
function validateMScenario($ms){
// These var's safe if the requirements are fullfilled
$is_customer_number_set = 0
$is_weight_set = 0
$is_package_set = 0
// Again iterate over nodes
foreach($ms->children as $child){
//check for customer number
if($child->getName() == "customerNumber"){
if($is_customer_number_set == 1){
echo "You just need one customer number I guess?!"
return -1
}
value = (string) $child;
// Check if customer number is existing
if(strlen(value) == 0 || !is_int(value) || intval(value) == -1){
echo "Dude you need a number!";
return -1
}
$is_customer_number_set = 0;
}
else if($node->getName() == "parcel-characteristics"){
//Ok I hope it should be pretty clear what to do here!
//...
}
else{
//Remove node again?
}
}
// All requirements fullfilled?
return ($is_customer_number_set && $is_weight_set && $is_package_set);
}