Restful Rails Edit vs Update

Question

I was trying to redirect to a different page after editing an entry, I assumed that it was using the update code because you are updating the database. It took me some time to realise that I was using the wrong action in the controller. Can someone please explain how edit and update work. Why are there two different actions? what are the differences between them?

Solution 1

edit action is responsible for rendering the view

update action is responsible for interacting with the model (db updates etc)

If you run rake routes you will see the difference between the verb and the action. Typically, the create/update actions are used when submitting a form. This differs from the new and edit actions as these are used to render the view (that displays the form to be submitted).

Solution 2

Another perspective - a bit redundant to highlight similarities and differences:

New is the precursor action to render a form, that upon submitting, runs the Create action. (the view is typically redirected back to the index view showing a list of similar items you already created)

Edit is the precursor action to render a form, that upon submitting, runs the Update action. (the view is typically redirected back to the index view showing a list of similar items you already created)

Comments

[Rumpleteaser]

in what order are they called? what process does it go through? edit -> update -> edit? If i put a redirect in edit it won't get to the update?

[theIV]

Correct. If you want to redirect someone after they have updated an entry, you put the redirect in the update action.

[Joost Schuur]

So just 2 events in that chain: edit, which renders the form, then update, when the user submits it. If you redirect_to to go the a different page (default is often the show view in a scaffold), then you'd have a third one.

[stevec]

thanks for explaining this in a way a beginner can understand!