[SOLVED] Bizarre database corruption issue?

[AdamM]

Hello all,

I have a mostly-complete Prestashop site under development for a client, and I'm getting a very strange bunch of error symptoms I'm hoping someone can help me out with. I'm using PS 1.4.6.2

 

The problem first appeared after I'd tried, as an experiment, putting an 'add to cart' button on one of the CMS pages, using the same href value as the button for that product on the category page.

 

When I clicked this link nothing appeared to happen, but afterward when I tried to follow another link to a different page, I got the "TECHNICAL ERROR: unable to add product" alert popup. I removed the test 'add to cart' link from the CMS page, and went on with development.

 

But then, when I next tried to add a product to the cart normally from one of the category or product pages, the same thing happened! Since then, more strange symptoms have appeared:

 

Initially, on a fresh browser session, everything on the site seems to function as normal as long as I don't try adding any products to the cart. After I try adding a product to the cart, though, pageloads get extremely slow (~30s), and most of the links disappear from the site's footer! (see screenshot)

 

I tried switching to the non-ajax cart, but a similar thing happens. The product gets added to the cart, and the cart page loads, but the header links are missing and the entire footer is gone. (see screenshot). Then, if I go back try to add another product to the cart, it shows a 'product is no longer available' error, and after that it won't load any front office pages at all. The browser (Firefox) just shows a 'connecting...' message but the server never seems to send anything back to the browser. The same symptoms happen when tested with IE.

 

If I clear my browser cache or delete the PS cookie, everything returns to normal.

 

I have confirmed that mbstring is enabled on the server. I also tried truncating the cart and cart_products tables, but to no effect.

 

To see the weirdness in action, go to http://miles.canvasd...~gatherin/shop/ Cart is currently set to non-ajax.

 

Does anyone know what could be causing this? Are there files that get modified by the application that could have been corrupted, or does it sound like a database problem? Where in the DB would the problem likely be?

 

Thanks very much for your help,

 

Adam

 

Edited May 18, 2012 by AdamM (see edit history)

[AdamM]

Turns out this had nothing to do with the database or the cart, but was actually caused by the Canada Post shipping module. It appears the web host started blocking port 30,000 (again) right about when I was experimenting with custom add-to-cart buttons, and the errors the shipping module was having borked the whole app.

 

When I uninstalled the CP shipping module, the cart started working properly again. Beware of the Canada Post module!!! A simple failure to connect to the Canada Post server seems to be able to put the whole Prestashop system into a gradual catastrophic spasm.

 

Adam