Add when to query builder

[josephmancuso]

We should be able to specify a when method that receives a conditional and then optionally calls the lambda or function callback:

Example:

age = 25

User.when(age >= 18, lambda q: q.where('age_restricted', 1))

[Marlysson]

Is it like a chain of where methods?

[josephmancuso]

yeah it can be chained. Its just if the first parameter is truthy then run the callback in the second parameter. Would look something like this:

# QueryBuilder

def when(conditional, callback):
    if conditional:
        callback(self)
    return self

[Marlysson]

A doubt, the attribute "age" in "when" method... is it evaluate from conditional from outside model or every line that checks every line from User model where age it's >= 18 and in case truthy then run callback method?

[josephmancuso]

No its just a normal conditional. Maybe a more obvious use case is:

def show(self, request: Request):
    User.when(self.request.input('age') >= 18, lambda q: q.where('age_restricted', 1)).get()

Its just true or false, removing the variables will just look like this:

User.when(True, lambda q: q.where('active', 1)).get()
# SELECT * FROM `users` WHERE `active` = '1'

User.when(False, lambda q: q.where('active', 1)).get()
# SELECT * FROM `users`