Devise update user without password

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Allow users to edit their account without providing a password

It shows how to do it for rails 3 and rails 4

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John's solution is a simpler alternative

I think this is a much better solution:

if params[:user][:password].blank? && params[:user][:password_confirmation].blank?
    params[:user].delete(:password)
    params[:user].delete(:password_confirmation)
end

This prevents you from having to change the Devise controller by simply removing the password field from the form response if it is blank.

Just be sure to use this before @user.attributes = params[:user] or whatever you use in your update action to set the new parameters from the form.