Ruby on Rails: How may create a quoted string to a request header?

Question

I am writing from scratch a Twitter client and one of the requisites is not using Twitter gems, so I must create my own requests.

Twitter API documentation says here that I must have a Authorization header like this:

Authorization:
OAuth oauth_consumer_key="xvz1evFS4wEEPTGEFPHBog",
oauth_nonce="kYjzVBB8Y0ZFabxSWbWovY3uYSQ2pTgmZeNu2VS4cg",
oauth_signature="tnnArxj06cWHq44gCs1OSKk%2FjLY%3D",
oauth_signature_method="HMAC-SHA1",
oauth_timestamp="1318622958",
oauth_token="370773112-GmHxMAgYyLbNEtIKZeRNFsMKPR9EyMZeS9weJAEb",
oauth_version="1.0"

As you may see I must have something like oauth_consumer_key="xvz1evFS4wEEPTGEFPHBog" with the second part in quotes. I tried using %Q like in

["oauth_consumer_key",%Q( Figaro.env.TWITTER_ACCESS_TOKEN )].join('=')

assuming %Q would return a quoted string. but when I inspect the value, all I get is

oauth_consumer_key=xvz1evFS4wEEPTGEFPHBog

which, obviously, is different from the required result.

What am I missing?

Answer 1

%Q(x) is basically the same as "x".

To achieve the desired result you have to manually introduce quotes into %Q expression, like this: %Q("#{Figaro.env.TWITTER_ACCESS_TOKEN}")

Answer 2

1. My solution:

'oauth_consumer_key="#{Figaro.env.TWITTER_ACCESS_TOKEN}"'

2. Why:

%Q() basically replaces the variable with double quotes "" , it is literally the same as if you wrote "Figaro.env.TWITTER_ACCESS_TOKEN"

In fact, to display the content of a variable, you have to use interpolation instead of the name itself, using "#{var}" .

You can also use %Q directly with interpolation using %Q{var} (note {} instead of () ).

Your problem is elsewhere: with the join() method. It's getting rid of double quotes. In that case doing ["var", var].join('=') and ["var", %Q{var}].join('=') ends doing exactly the same thing but more complicated.

@Artem Ignatiev's solution should works . But if you need to be more readable, you don't even need to join, imho, it makes sense only when you are using more than two variables.

For instance, I will use something like 'oauth_consumer_key="#{var}"' mixing single and double quote to make sure it causes no confusions.

If you do need to use %Q() and join , you can still use ["oauth_consumer_key", %Q("#{Figaro.env.TWITTER_ACCESS_TOKEN})].join('=') .

• Note that because of the join you can use single quote interpolation %q or double quote interpolation %Q without affecting the ends results:

eg

['oauth_consumer_key', %q("#{var}")].join('=') == ["oauth_consumer_key", %Q("#{var}")].join('=')