Create Methods to auto-generate data

[alexstandiford]

I <3 command-line generators. They allow us developers to debug our own code quickly, create better unit tests, and create quick on-the fly scripts to help illustrate problems to other people.

Unfortunately, a data generator is almost never created before a plugin has been completely built, simply because it takes a significant amount of time to build, even though it would be extremely helpful if one was prepared early-on.

I think Berlin could solve this problem.

Ideally, Berlin would have a way to generate data with a PHP method, and possibly a WP_CLI command. It's possible the CLI would need to be in a separate library, since BerlinDB isn't necessarily specific to WordPress.

But how would we associate data with other tables in a generator? Data is usually interconnected in some manner. A good example of this is in AffiliateWP:

A referred transaction needs a referral.
A referral needs an affiliate, a customer, and an order.
An order needs a customer, and products.
An affiliate needs a user ID
A customer needs a user ID

On a basic level, you could create generator methods that would generate affiliates, customers, orders, users, and products individually. This would require 6 separate commands:

wp berlindb generate users --number=10
wp berlindb generate customers --number=1 --users="1,2,3,4,5,6,7,8,9,10"
wp berlindb generate affiliates --number=1 --users="1,2,3,4,5,6,7,8,9,10"
wp berlindb generate products --number=10
wp berlindb generate orders --number=10 --products="1,2,3,3,4,5,6,7,8,9,10"
wp berlindb generate referrals --number=10 --orders="1,2,3,4,5,6,7,8,9,10" --affiliates=1 -- customers=1

Even if you chain these commands together, that's an awful lot of work to build out a test database. It works, it's just not as simple as it could be.

Ideally, it should be possible to configure, and do something more like this:

wp berlindb generate orders --number=10

The simplest solution I can think of is to create a method in the schema, generate that can be overridden by child classes. This would provide a fairly straightforward way to override how generation functionality would work for individual classes.