raise exception when retry limit is exceeded

lib/rack-idempotent.rb

@@ -2,6 +2,10 @@
 
 module Rack
   class Idempotent
+    RETRY_LIMIT = 5
+
+    class RetryLimitExceeded < Exception; end
+
     def initialize(app)
       @app= app
     end
@@ -11,8 +15,12 @@ def call(env)
       begin
         @app.call(env)
       rescue Errno::ETIMEDOUT
-        env['client.retries'] += 1
-        retry
+        if env['client.retries'] > RETRY_LIMIT - 1
+          raise(RetryLimitExceeded)
+        else
+          env['client.retries'] += 1
+          retry
+        end
       end
     end
   end

spec/rack-idempotent_spec.rb

@@ -5,21 +5,40 @@ class CaptureEnv
     class << self; attr_accessor :env; end
     def initialize(app); @app=app; end
     def call(env)
-      tuple = @app.call(env)
+      @app.call(env)
+    ensure
       self.class.env = env
-      tuple
     end
   end
+  class RaiseUp
+    class << self; attr_accessor :errors; end
+    def self.call(env); self.errors.shift.tap{|e| raise(e) if e}; [200, {}, []]; end
+  end
+  before(:each){ CaptureEnv.env = nil }
   it "should retry Errno::ETIMEDOUT" do
-    $to_raise = [Errno::ETIMEDOUT, Errno::ETIMEDOUT]
-
+    RaiseUp.errors = [Errno::ETIMEDOUT, Errno::ETIMEDOUT]
     client = Rack::Client.new do
       use CaptureEnv
       use Rack::Idempotent
-      run lambda{|env| $to_raise.shift.tap{|e| raise(e) if e}; [200, {}, []]}
+      run RaiseUp
     end
-    response = client.get("/doesntmatter")
+
+    client.get("/doesntmatter")
+
     env = CaptureEnv.env
     env['client.retries'].should == 2
   end
+  it "should raise Rack::Idempotent::RetryLimitExceeded when retry limit is reached" do
+    RaiseUp.errors = (Rack::Idempotent::RETRY_LIMIT + 1).times.map{|i| Errno::ETIMEDOUT}
+    client = Rack::Client.new do
+      use CaptureEnv
+      use Rack::Idempotent
+      run RaiseUp
+    end
+
+    lambda { client.get("/doesntmatter") }.should raise_exception(Rack::Idempotent::RetryLimitExceeded)
+
+    env = CaptureEnv.env
+    env['client.retries'].should == Rack::Idempotent::RETRY_LIMIT
+  end
 end