Using twitter_oauth from the Command Prompt

Several days ago I began work on Turpentine, a Twitter client written in Ruby that currently runs as a CLI. After I got things working to my satisfaction, I decided to add OAuth — partly because the whole project is meant to give me exposure to a variety of stuff I’m not familiar with, and partly because Twitter will remove basic auth at some point in the future.

After going through the Ruby on Rails example, I got stuck at the post-authorization point — the example assumes the user will be in a browser, which obviously doesn’t work for me at the command prompt.

I tried to figure out the solution using the sample code and the OAuth gem it uses, but it was beyond my level. (Though I did learn that all the OAuth information is passed around using query strings.) At this point I decided I’d give up on trying to write the code myself, and switched over to the twitter_oauth gem. The sample code was tremendously helpful, and needed only a little modification to handle my scenario.

---

Because I’m working purely in Ruby in the moment, I’ve kept things simple by using YAML to manage login information.

Step one is to load the config.

CONFIG_FILE = 'config.yaml'
CONFIG = YAML::load(File.read(CONFIG_FILE))

The relevant part of the config looks like this:

oauth:
    consumer_key:
    consumer_secret:
    request_token: 
    request_secret:

I’ve registered my application for Oauth, so I’ve filled in the consumer_key and consumer_secret fields. (Not shown because the secret must be kept secret.)

Note: if you’re going to use the command prompt like I am, specify that your application is a client, not a browser.

Back to code. I begin by loading the values:

consumer_key = CONFIG['oauth']['consumer_key']
consumer_secret = CONFIG['oauth']['consumer_secret']
request_token = CONFIG['oauth']['request_token']
request_secret = CONFIG['oauth']['request_secret']

Check if the application has been authorized (i.e. check if the request_ fields have any information):

if request_token.nil? and request_secret.nil?
  # not yet authorized
else
  # authorized
end

Authorization is the most code-heavy part of the process.

if request_token.nil? and request_secret.nil?
  client = TwitterOAuth::Client.new(
       :consumer_key => consumer_key,
       :consumer_secret => consumer_secret
       )
  request_token = client.request_token

  …

Here, we give twitter_oauth the application’s key and secret and let it work out the address that we’ll use to authorize Twitter access.

  …

  puts "Please open the following address in your browser to authorize this application:"
  puts "#{request_token.authorize_url}\n"

  puts "Hit enter when you have completed authorization."
  STDIN.gets

  …

The user is then prompted to open the address, which will ask if they really do want to authorize the application:

Finally, we put the user’s new request token and secret into the configuration file:

  …

  access_token = client.authorize(
      request_token.token,
      request_token.secret
  )

  File.open(CONFIG_FILE, 'w') do |out|
    CONFIG['oauth']['request_token'] = access_token.token
    CONFIG['oauth']['request_secret'] = access_token.secret
    YAML::dump(CONFIG, out)
  end
else
…

Things are a lot simpler if we’re already registered:

…
else
  client = TwitterOAuth::Client.new(
    :consumer_key => consumer_key,
    :consumer_secret => consumer_secret,
    :token => request_token,
    :secret => request_secret
  )
end

Now that we have a functional login, we can use the gem’s built-in functionality to do useful things like get the friends timeline:

puts client.friends_timeline

And proceed as if everything used basic auth.