tcrayford

# caching constraint
module Blog
  Routes = Raptor.routes(Blog) do
    show :to => 'Post.find', :unless :post_cached
    show :responder => NoContentResponder
  end
  
  class PostCached
    def match?(id, cache_control)
      post = Post.find(id)

tcrayford

module Blog
  Routes = Raptor.routes(Blog) do
    show :to => 'Post.find', :http_cache_requirement => :post_cached
  end

  class PostCached
    def match?(id, cache_control)
      post = Post.find(id)
      post.updated_at =< cache_control
    end

tcrayford

module Blog
  Routes = Raptor.routes(Blog) do
    show :to => 'Post.find', :if => :post_not_cached
  end

  class PostNotCached
    def match?(id, cache_control)
      post = Post.find(id)
      post.updated_at =< cache_control
    end

tcrayford

(unfinished bar)

(defn foo [stuff incoming]
  (first
    (filter
      (fn [a-thing]
        (bar a-thing incoming))
    stuff)))
  
;; this actually calls bar

tcrayford

module Kernel
  def an(value)
    Thingy.new(value)
  end

  def none
    Nothing.new
  end
end

tcrayford

# with dependency injection, and slightly different route syntax:
module WebCrawler
  Routes = Raptor::App.new(self) do
    queue = #... some sort of persistent queue initialized here
    crawler = WebCrawler.new(queue)

    path "to-be-crawled" do
      create crawler, :enqueue!, :require => :logged_in
    end
  end

tcrayford

Note, the "don't stub external APIs" is a rule, but like all design/testing rules it *should* be broken with good judgement. Furthermore, like all design/testing rules, the best way to learn when to break it is to follow it rigorously until it leads you to a bad place.

Problems
--------

- Stubbing external APIs gives you no design feedback: you cannot change the third party API (unless you monkey patch, but seriously, Fuck That Shit. Since stubbing/mocking are primarily a design tool (for me), having to stub/mock something I cannot/will not change seems pointless.
- Stubbing a third party API relies on you having intimate understanding of the docs, including error conditions, timeouts etc. I'm not confident in my ability to successfully stub a third party API on each conditions.

The Solution
------------

tcrayford

1.9.3p125 :001 > class Foo < RuntimeError; def to_str; "other_string"; end; end
 => nil 
1.9.3p125 :002 > begin raise Foo.new; rescue Foo => e; end
RuntimeError: other_string
	from (irb):2
	from /Users/tcrayford/.rvm/rubies/ruby-1.9.3-p125/bin/irb:16:in `<main>'

tcrayford

  specify "the first time rspec has made me sad" do
    class CustomError < RuntimeError; end
    expect do
      raise CustomError.new('what')
    end.to raise(CustomError.new('what'))
  end

tcrayford

  specify "the first time rspec has made me sad" do
    class CustomError < RuntimeError; end
    expect do
      raise CustomError.new('what')
    end.to raise_error(CustomError.new('what'))
  end