XML parser using shopify webhooked line-items - php

Question

I am using shopify webhook to update my sql server's 'qty' field when order updated, below is my php code
?php
$xmlData = fopen('php://input' , 'rb');
while (!feof($xmlData)) { $xmlString .= fread($xmlData, 4096); }
fclose($xmlData);
$xml = new SimplexmlElement($xmlString);
file_put_contents('orders/order' . '.xml', $xmlString);
$dom = new DomDocument();
$dom->load('orders/order.xml');
$itemList = $dom->getElementsByTagName('line-item');
foreach($itemList as $item) {
$sku='';
$qty='';
foreach($item->childNodes as $child) {
if ($child->localName == 'sku') {
$sku = $child->textContent;
}
if ($child->localName == 'quantity') {
$qty = $child->textContent;
}
}
mysql_connect ("?????????????????????????");
mysql_select_db("??????????");
$query = "UPDATE xcart_categories SET product_count = product_count - $qty WHERE description='$sku';";
mysql_query($query);
}
and below is xml file i am getting from shopify webhook
<?xml version="1.0" encoding="UTF-8"?>
<order>
<buyer-accepts-marketing type="boolean">true</buyer-accepts-marketing>
<closed-at type="datetime" nil="true"></closed-at>
<currency>USD</currency>
<email>yeongju_l#yahoo.com</email>
<financial-status>pending</financial-status>
<fulfillment-status>fulfilled</fulfillment-status>
<gateway>Local Pick-Up</gateway>
<id type="integer">140303247</id>
<name>#1012</name>
<note></note>
<number type="integer">12</number>
<subtotal-price type="decimal">0.2</subtotal-price>
<taxes-included type="boolean">false</taxes-included>
<total-discounts type="decimal">0.0</total-discounts>
<total-line-items-price type="decimal">0.2</total-line-items-price>
<total-price type="decimal">0.2</total-price>
<total-price-usd type="decimal">0.2</total-price-usd>
<total-tax type="decimal">0.0</total-tax>
<total-weight type="integer">0</total-weight>
<updated-at type="datetime">2012-09-16T21:20:07-04:00</updated-at>
<created-at type="datetime">2012-09-16T21:08:30-04:00</created-at>
<token>dcf523d93c68159c15a7c8d1fabbee07</token>
<landing-site>/products/test</landing-site>
<referring-site></referring-site>
<cancelled-at type="datetime" nil="true"></cancelled-at>
<cancel-reason nil="true"></cancel-reason>
<cart-token>a9a7bc5d8103f6a3bb45e827f0cb8928</cart-token>
<browser-ip nil="true"></browser-ip>
<landing-site-ref nil="true"></landing-site-ref>
<order-number type="integer">1012</order-number>
<discount-codes type="array"/>
<note-attributes type="array">
</note-attributes>
<processing-method>manual</processing-method>
<line-items type="array">
<line-item>
<id type="integer">228531213</id>
<requires-shipping type="boolean">false</requires-shipping>
<fulfillment-service>manual</fulfillment-service>
<grams type="integer">0</grams>
<price type="decimal">0.2</price>
<quantity type="integer">1</quantity>
<sku>1234567</sku>
<title>test</title>
<product-id type="integer">104663831</product-id>
<variant-id type="integer">240660979</variant-id>
<vendor>5 Second</vendor>
<variant-title nil="true"></variant-title>
<fulfillment-status>fulfilled</fulfillment-status>
<name>test</name>
<variant-inventory-management></variant-inventory-management>
<properties type="array">
</properties>
</line-item>
</line-items>
<shipping-lines type="array"/>
<tax-lines type="array">
<tax-line>
<title>NY State Tax</title>
<price type="decimal">0.0</price>
<rate type="float">0.04</rate>
</tax-line>
<tax-line>
<title>Queens County Tax</title>
<price type="decimal">0.0</price>
<rate type="float">0.04875</rate>
</tax-line>
</tax-lines>
<billing-address>
<first-name>Yeongju</first-name>
<last-name>Lee</last-name>
<address1>14809 northern blvd</address1>
<address2></address2>
<city>Flushing</city>
<company></company>
<country>United States</country>
<phone></phone>
<province>New York</province>
<zip>11354</zip>
<latitude type="decimal">40.76529</latitude>
<longitude type="decimal">-73.81831</longitude>
<name>Yeongju Lee</name>
<country-code>US</country-code>
<province-code>NY</province-code>
</billing-address>
<fulfillments type="array">
<fulfillment>
<id type="integer">67712419</id>
<order-id type="integer">140303247</order-id>
<created-at type="datetime">2012-09-16T21:20:07-04:00</created-at>
<updated-at type="datetime">2012-09-16T21:20:07-04:00</updated-at>
<tracking-number nil="true"></tracking-number>
<tracking-company nil="true"></tracking-company>
<status>success</status>
<service>manual</service>
<tracking-url>http://www.google.com/search?q=</tracking-url>
<receipt>
</receipt>
<line-items type="array">
<line-item>
<id type="integer">228531213</id>
<requires-shipping type="boolean">false</requires-shipping>
<fulfillment-service>manual</fulfillment-service>
<grams type="integer">0</grams>
<price type="decimal">0.2</price>
<quantity type="integer">1</quantity>
<sku>1234567</sku>
<title>test</title>
<product-id type="integer">104663831</product-id>
<variant-id type="integer">240660979</variant-id>
<vendor>5 Second</vendor>
<variant-title nil="true"></variant-title>
<fulfillment-status>fulfilled</fulfillment-status>
<name>test</name>
<variant-inventory-management></variant-inventory-management>
<properties type="array">
</properties>
</line-item>
</line-items>
</fulfillment>
</fulfillments>
<customer>
<id type="integer">96489088</id>
<email>yeongju_l#yahoo.com</email>
<accepts-marketing type="boolean">true</accepts-marketing>
<first-name>Yeongju</first-name>
<last-name>Lee</last-name>
<orders-count type="integer">12</orders-count>
<total-spent type="decimal">16.26</total-spent>
<note nil="true"></note>
<created-at type="datetime">2012-08-17T11:31:50-04:00</created-at>
<updated-at type="datetime">2012-09-16T21:20:07-04:00</updated-at>
<state>enabled</state>
<last-order-id type="integer">140303509</last-order-id>
<tags>C</tags>
<last-order-name>#1013</last-order-name>
</customer>
like you see i got two sku and qty because of duplicated line-item so for example when customer order one "product name - test in this case i got "-2" quantity update in my sql server sku test field , but when i am using webhook event when order creation it worked i mean i see only one line item but all the other cases(when order updated, when order payment, when order fullfillment..) show me duplicated line item even there is only one item ordered
i think i am parsing my XML badly
anyone who can teach me correct code to pull 'line items' from the first line-items node i will really appreciate it! Thanks..again

Answer 1

You're doing a lot of redundant steps to parse your XML there. You don't need to save the data into a file before processing it, and you have a stray call to SimpleXML that you're not using. All you need is this:
$xmlString = file_get_contents('php://input');
$dom = new DomDocument();
$dom->loadXML($xmlString);
After that, your parsing logic looks fine but you are only ever running one SQL query, with one SKU in it.
Inside your foreach loop, you define the variables $sku and $qty, but you don't do anything with them inside the loop. So next time round the loop, you will over-write their values, and nothing will ever know about the old values.
There are few ways to do this:
run SQL inside the loop (not very efficient)
build up an array of SKUs and quantities ($sku[] = ...; $qty[] = ...;) and then build your SQL from these arrays
slightly tidier, build a single array with the SKU-quantity pairs as nested arrays ($sku_list[] = array('sku' => ..., 'qty' => ...))
build your SQL string progressively inside the loop ($sql .= '...') and execute it once at the end