ActiveRecord: save_only_valid_attributes?

Rails
1

Hello,

I’m looking for a variation on the “save” method, that will only save
attributes that do not have errors attached to them.

So a model can be updated without being valid overall, and this will
still prevent saving invalid data to the database.

I’ve been looking through the Rails code for a while now, and I’ve
been unable to find anything that might work. Does anyone have an
ideas for how I can accomplish this?

Thanks for your time,
Brady

2

You could solve it by doing something like this?

def save_valid_attributes
self.valid?
self.attributes.each do |k,v|
self.update_attribute(k.to_sym, v) unless
self.errors.on(k.to_sym)
end
end

Rob L.

3

something like

def save_valid_attributes
valid?
update_atrtibutes attributes.inject({}){|k, v, m| m[k] = v unless
errors_on(k.to_sym); m}
end

would save you multiple hits on the db for single attributes. check out
Enumerable#inject for more information
http://www.ruby-doc.org/core/classes/Enumerable.html#M003160

HTH

RSL

4

Russell N. wrote:

def save_valid_attributes
valid?
update_atrtibutes attributes.inject({}){|k, v, m| m[k] = v unless
errors_on(k.to_sym); m}
end

And note this violates the GUI principle of least surprise.

If a customer were changing credit card and billing address at the same
time,
they don’t need the billing address to stick in the database when the CC
bounces.

I’m aware the actual problem may be different here…

–
Phlip

5

Thanks, that inject code will work nicely!
And yes, I’m a good like interface designer, due to the nature of what
I’m working on there is lots of partial updates to data before the
model instance is full and valid, and the user is notified that
partial updates are saved.

Thanks again, I appreciate it.

-Brady

6

it still violates it in the original code. it just violates it with less
db
hits.

RSL