Let’s face it – there are some features in WordPress which are unloved and rarely used. Ever used Press This? I’d love to see WordPress cutting out some bloat to make core lighter, and as a consequence easier to use. Here are my thoughts on what should be killed.
Sometimes code needs to change; without doing so you can end up with a non-consistent, bloated mess. When changing things such as functions and hooks however, you do have to consider backwards compatibility so that code which relies on the old things doesn’t just stop breaking without explanation.
In WooCommerce major releases we often have to deal with this problem – in this post I’ll explain how to deprecate code, and how we dealt with it whilst developing 2.1.
Up until 2.1, each order had to be shipped via a single method with a single price. 2.1 changes that and allows each package to be quoted and shipped individually.
By default, each order is a package, so to get this new functionality to kick in you must split it into multiple packages first.
Filtering the packages
Each package has cart items, a total cost, applied coupons, and the destination:
Once items are placed into this package, the package is then filtered through the woocommerce_cart_shipping_packages hook. This is where you can manipulate the packages and create more if needed.
Lets say for this example we have a regular items and a bulky item in our cart:
The bulky item cannot ship with regular items, so we give it a shipping class called ‘Bulky’ and then filter the packages to separate it out via some code:
This code puts bulky items in one package, and regular items in another – once done, during cart and checkout you will get a shipping section per-package, and each can be chosen independently:
Limiting available methods for a package
Each package can now also be marked to ‘ship via’ a method of your choosing. This is useful if certain packages can only be shipped by certain methods.
For this example, lets ensure bulky items are only shipped via flat rate, and not shipped for free.
Notice the ‘ship_via’ row which has been added. Now during cart and checkout, only flat rate will be allowed for the bulky items:
After an order is placed, this is displayed in the backend like this:
So how can this new feature be used? Here are some example use cases:
Shipping method restrictions
Per product shipping with a different selectable method per product
True per-product shipping costs
Shipping per class
Free shipping for qualifying products only, not the whole cart
Right now its obviously only do-able via code, but I plan on building some extra functionality into the per-product shipping plugin to use this at some point, and I’m sure someone will make a UI for this eventually 🙂