Shipping module dev - Basic questions

[blackhatbrigade]

I need to make a proprietary shipping module for VM.  I'm still new to VM and only partially familiar with Joomla!.  I understand Joomla! questions are out of scope here, but I'm thinking my questions will be pertinent to only VM.

1) I found shipping modules (forgive me if I'm using the wrong word for that) in /administrator/components/com_virtuemart/plugins/shipping/    I'm mostly concerned with the USPS module because it's functionality is very close to what I need.  Is this the only place for shipping mod files?

2) Is there any online documentation to what product information I can access from within the shipping mod scope?  I obviously need to pull weight, size, etc., but I also need to pull custom product attributes (for LTL shipping).  Any redirection to a good online doc would be appreciated (The VM API seems to be a little out of date... that or I'm not seeing the whole picture with it).

I apologize if this is a redundant post.  I tried to search for the info before posting.  I didn't have much luck.  I would be grateful if someone has any links to resources that may help.

[blackhatbrigade]

Figured it'd be in the wiki, but it was somewhere else.  For anyone else looking for the online documentation for shipping development...  http://virtuemart.net/documentation/Developer_Manual/Shipping_Modules.html

[blackhatbrigade]

I've been working with this for a while now and wanted to do a follow up, plus ask another question.

The best documentation I've found on Shipping Module development to date is: http://virtuemart.net/documentation/Developer_Manual/Shipping_Module_API.html  Which is part of the on-site manual.  It does specify the locations of the pertinent files to be added.  The other link I posted had some terribly out of date information.

My second question I ended up having to do a little bit of experimentation to find what I was needing.  I added the desired field to the product table and then mirrored that on the product pages.  It seems to work great (side note:  I love the DB interface in the VM code.  It's wonderously easy to use).

My new question is related to a problem I'm having.  I've got my module displaying the information I want and everything appears to work great, until you get to step 3 of the checkout.  Then I get a message saying: Error: Please select another Shipping Method.  I've gone over the validate and get_rate functions.  I don't see anything wrong with them.  My list_rates function does nearly the same thing as the USPS module in that it lists radio inputs with the name="shipping_rate_id" and the correct formatted value (minus the rate_id part, as it was listed as optional).   I'm not fully understanding the importance of the id="" field and was thinking that perhaps that was an issue...

Thinking that maybe the problem is with how I'm listing the radio inputs, here is the actual code:

Code Select Expand


<input type="radio" name="shipping_rate_id" value="priorityone%7CPriorityOne%7CSaia%7C183.76" id="SAIA" />
<label for="priorityone%7CPriorityOne%7CSaia%7C183.76">LTL - Saia <strong>(183.76)</strong><br>


My module generates more than just one entry like this, but they all follow this layout.

If that looks good, then I guess I'm just not sure what would cause the checkout to fail when this shipping option is checked.

Any help would be appreciated.

[blackhatbrigade]

After some digging (a lot actually), I found that that error is due to a failure for the Shipping Modules validate function (it returns false on validation attempt).

The validation method needs to validate that "shipping_rate_id" is set on the $d variable passed to it.  (I was trying to validate a SESSION element, which oddly enough the USPS module does do something with the SESSION variable)