如何在 model 方法和 Rails 3 的控制器中使用 DRY 重复代码？

Question

I have the following methods for a single model, and may have more. I may also have some of the repeated code in a helper. How can I make it DRY?

25   def full_name
 26     client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
 27     client.authorize_from_access(self.atoken, self.asecret)
 28     client.profile(id => self.uid)
 29     client.profile.first_name + " " + client.profile.last_name
 30   end
 31 
 32   def image_url
 33     client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
 34     client.authorize_from_access(self.atoken, self.asecret)
 35     client.profile(id => self.uid)
 36     client.profile(:fields => "picture-url").picture_url
 37   end

The code where I instantiate the client and access the profile id for the most part is repeated everytime I need to make a method call on the API. It's just the API that changes.

What happens when I also need to call in the controller (of a different model?)

29     if @review.save
 30       flash[:notice] = "Successfully created review."
 31       # check if allowed to post to LinkedIn and post
 32       if @review.post_linkedin?
 33         client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
 34         client.authorize_from_access(current_user.atoken, current_user.asecret)
 35         debugger 
 36         client.update_network("has shared expertise on <a")
 37       end

How could I make it more dry?

Answer 1

I agree with @thekindofme, but I would add some caching, so you don't have to do a LinkedIn API call every time:

def linkedin_profile
  @linkedin_profile ||= set_linkedin_profile
end

def set_linkedin_profile
  client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
  client.authorize_from_access(self.atoken, self.asecret)
  client.profile(id => self.uid)
  client.profile
end

def full_name
  linkedin_profile.first_name + " " + linkedin_profile.last_name
end

def image_url
  linkedin_profile(:fields => "picture-url").picture_url
end

Answer 2

General rule is: extract the code that is repeated everywhere put it in a reusable class/method..etc.

for the above code. you could do something like:

def get_client_profile
      client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
      client.authorize_from_access(self.atoken, self.asecret)
      client.profile(id => self.uid)
      client.profile
end

def full_name
  p=get_client_profile
  p.first_name + " " + p.last_name
end

...etc

In this case you can have the get_client_profile in your model(may be in model Client?). As 'it belongs their'.

Answer 3

I would add the following methods to your user class:

class User
  def linkedin_client
    @linkedin_client || = get_linkedin_client 
  end

  def linkedin_profile
    linkedin_client.profile(id => self.uid)
    linkedin_client.profile
  end

  def full_name
    linkedin_profile.first_name + " " + user.linkedin_profile.last_name
  end

  def image_url
    linkedin_profile(:fields => "picture-url").picture_url
  end


  private

  def get_linkedin_client
    client = LinkedIn::Client.new(ENV['LINKEDIN_KEY'], ENV['LINKEDIN_SECRET'])
    client.authorize_from_access(atoken, asecret)   
    client     
  end
end

and inside your controller you would write:

if @review.save
  flash[:notice] = "Successfully created review."
  # check if allowed to post to LinkedIn and post
  if @review.post_linkedin?
    current_user.linkedin_client.update_network("has shared expertise on <a")
  end
end

Hope this helps.