PHP 5 e-commerce Development- P25 ppt

Chapter 4 [ 103 ] One important aspect of this code is that, each set of attribute values is cached, and then added as a tag for the template engine after the attribute sets themselves have been converted into tags. This is because the template system processes the tags in order, so if it doesn't do the attributes rst, it won't nd the tags it generates, which are replaced with the attribute values, as explained in the next section, Templates. Templates We have looked into how to alter the framework to use different templates depending on if the product has customizable attributes. The next stage is to actually make these templates. We need a template for the product with attributes. This template requires a nested loop of template tags: the outer loop of template tags will be to generate a drop-down list for each attribute, the inner loop to generate the attributes for each of the attribute drop-down lists. <h2>{product_name}</h2> {product_description} <p>Cost: &pound;{product_price}, number in stock {product_stock} . Weight: {product_weight}Kg. </p> <p> <img src="product_images/{product_image}" alt="{product_name} image" /> </p> <! START attributes > <select name="attribute_{attribute_name}"> <! START values_{attribute_name} > <option value="">{value_name}</option> <! END values_{attribute_name} > </select> <! END attributes >attributes > > This is the same code as our product template, with a select eld. A drop-down list is generated for each set of attributes associated with the product, and then list items are generated where appropriate. This material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Product Variations and User Uploads [ 104 ] A look back at simple variants We discussed simple product variants earlier. One advantage that they have over multiple variants becomes obvious when page design becomes a concern. If we were to have a system that utilized simple variants, we could display a simple table of product variants on the "main products" page, listing the names of products, cost or cost difference, and a purchase button. Of course, this is something we could look at implementing as subproducts, should we wish to. Giving users control Along with giving users a choice for products in our store, we may also wish to give them some control over the products; for example, this could include: Uploading a photograph or image, for our Juniper Theatricals store; this will be for customers to order and purchase customized novelty t-shirts Supplying some custom text, again for our Juniper Theatricals store; this will be for customers to customize their novelty t-shirts with a punch line of their own, to t into the products template • • This material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Chapter 4 [ 105 ] How to customize a product? We need to make it possible for our customers to customize the product through both le and image uploads, and then entering of free text. Uploads If the product is to allow the customer to upload an image, then the template requires a le upload eld within it, to facilitate that. We are only going to look at allowing a single le upload for each product; if a product required multiple images, for instance print media, where back and front designs may be required, the customer can compress them into a single le. It may be worth considering implementing multiple le uploads per product at a later stage, should the requirements of our store demand it. Custom text The simplest way to handle custom text is to have at most one free text permitted per product. This would simply involve having an extra eld in the table to contain items held within a customer's basket, relating to the value from this eld, and also a eld in the products table indicating that the product can accept free text as an input. For many situations, this should be sufcient; however, let's look at a potential way we could support multiple text elds. In our Juniper Theatricals store, we will want to advertise customizable t-shirts for sale, with novelty text or images within them. If the customer is to supply some text, we may wish to provide them with options for entering text for the front, back, and perhaps even the sleeves, or below a logo, which may appear on the breast of the shirt. If we have an additional eld in our products table containing a list of free text attributes, we may wish to collect it from the user, and then generate text boxes for each of these attributes, and the submitted values could be serialized into an array and stored within a single eld in the customer's entry for the product in the basket items table, when we develop that in Chapter 6. This material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Product Variations and User Uploads [ 106 ] When viewing a product with custom text inputs, the appropriate text boxes appear within the view, as the following screenshot illustrates. Limitations to this method This method obviously has limitations. Primarily, because we store all of the custom text inputs available and their values in a single database eld, instead of one per value, it isn't going to be easy to search for product purchases based on the values submitted into these. Another limitation is that all of the text elds would need to be text input boxes, and we could extend this to support both input boxes and text areas, among other relevant and useful input boxes. Maintaining uploads In Chapter 6, we will look at processing these uploads; however, we will also need to consider maintaining them. If a le is uploaded and a product is added to a basket, and that basket is never converted into an actual order, we will want to remove that le. Similarly, once an order has been paid for, and processed fully, we would also want to remove it. This material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Chapter 4 [ 107 ] Security considerations There are also a number of security considerations which we must bear in mind: By allowing customers to upload les, we could be open to abuse from someone repeatedly uploading images to our server. We could implement time delays to prevent this. Which types of les will we allow customers to upload? We should check both the type of the le uploaded and the le extension against a list of suitable values. What would the maximum le size be for les customers upload? If we set this value to be too large, our server will get lled up quickly with custom les, or could be abused by someone purposely uploading very large les. What safeguards are in place to prevent customers nding uploads of other customers? Database changes To allow customers to customize products, we obviously need to make some changes to our database structure to indicate that a particular product is customizable, and can be customized either by the customer uploading a le or entering some text. Extending our products table The changes required to our products table are actually quite simple; we only need to add two elds to the table: allow_upload (Boolean): This eld is used to indicate if the customer is permitted or able to upload a le when adding the product to their basket. custom_text_inputs (longtext): This eld is used to hold a serialized array of free text elds, which we may wish to collect from our customers. The following SQL query will modify the table for us: ALTER TABLE `content_types_products` ADD `allow_upload` BOOL NOT NULL, ADD `custom_text_inputs` LONGTEXT NOT NULL ; • • • • • • This material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 . and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Chapter 4 [ 1 05 ] How to customize a product? We need to make it possible for our customers. material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Product Variations and User Uploads [ 104 ] A look back at simple. material is copyright and is licensed for the sole use by jackie tracey on 23rd February 2010 953 Quincy Drive, , Brick, , 08724 Product Variations and User Uploads [ 106 ] When viewing a product