Improved error handling by separating HTTP 4xx errors from HTTP 5xx e…

…rrors, so HTTP 4xx errors can be parsed first.

See http://github.com/jnunemaker/twitter/commit/6d76a3ae906bd36d78c3adbf5e79e61cefd0b580#comments for details.

HISTORY.rdoc

@@ -1,7 +1,7 @@
 === 1.0.0.rc.1 - October 12, 2010
 * {Switch from httparty to faraday HTTP client library}[http://github.com/jnunemaker/twitter/commit/80aff88dae11d64673fe4e025cc8f065a6796345]
 * {Switch from oauth to simple_oauth for authentication}[http://github.com/jnunemaker/twitter/commit/76cfe3749e56b2b486f2b5ffc9aa7f437cb2db29] (@laserlemon[http://twitter.com/#!/laserlemon])
-* {Handle errors with <tt>faraday_middleware</tt>}[http://github.com/jnunemaker/twitter/commit/1f99e46f602268bc82daf39b329d81e54abfb292]
+* {Handle errors in faraday middleware}[http://github.com/jnunemaker/twitter/commit/466a0d9942d1c0c0c35c6302951087076ddf4b82#diff-2]
 * {Add #NewTwitter methods and tests}[http://github.com/jnunemaker/twitter/commit/0bfbf6352de9bdda2b93ed053a358c0cb8e78e8f]
 * {Fix tests that assume position in a <tt>Hash</tt>}[http://github.com/jnunemaker/twitter/commit/c9f7ed1d9106807aa6fb27d48a92f4b92d0594a7] (@duncan[http://twitter.com/#!/duncan])
 * {Enable SSL by default (add option to disable SSL)}[http://github.com/jnunemaker/twitter/commit/c4f8907d6595f93d63bc84d6575920a14774e656]

lib/faraday/raise_http_4xx.rb

@@ -0,0 +1,33 @@
+module Faraday
+  class Response::RaiseHttp4xx < Response::Middleware
+    def self.register_on_complete(env)
+      env[:response].on_complete do |response|
+        case response[:status].to_i
+        when 400
+          raise Twitter::BadRequest, error_message(response)
+        when 401
+          raise Twitter::Unauthorized, error_message(response)
+        when 403
+          raise Twitter::Forbidden, error_message(response)
+        when 404
+          raise Twitter::NotFound, error_message(response)
+        when 406
+          raise Twitter::NotAcceptable, error_message(response)
+        when 420
+          raise Twitter::EnhanceYourCalm, error_message(response)
+        end
+      end
+    end
+
+    def initialize(app)
+      super
+      @parser = nil
+    end
+
+    private
+
+    def self.error_message(response)
+      "#{response[:method].to_s.upcase} #{response[:url].to_s}: #{response[:response_headers]['status']}#{(': ' + response[:body]['error']) if response[:body] && response[:body]['error']}"
+    end
+  end
+end

lib/faraday/raise_http_5xx.rb

@@ -0,0 +1,27 @@
+module Faraday
+  class Response::RaiseHttp5xx < Response::Middleware
+    def self.register_on_complete(env)
+      env[:response].on_complete do |response|
+        case response[:status].to_i
+        when 500
+          raise Twitter::InternalServerError, error_message(response, "Something is technically wrong.")
+        when 502
+          raise Twitter::BadGateway, error_message(response, "Twitter is down or being upgraded.")
+        when 503
+          raise Twitter::ServiceUnavailable, error_message(response, "(__-){ Twitter is over capacity.")
+        end
+      end
+    end
+
+    def initialize(app)
+      super
+      @parser = nil
+    end
+
+    private
+
+    def self.error_message(response, body=nil)
+      "#{response[:method].to_s.upcase} #{response[:url].to_s}: #{response[:response_headers]['status']}#{': ' + body if body} Check http://status.twitter.com/ for update on the status of the Twitter service."
+    end
+  end
+end

lib/twitter/base.rb

@@ -441,20 +441,22 @@ def build_multipart_bodies(parts) self.class.build_multipart_bodies(parts) end
 
     def connection
       builders = []
-      builders << Faraday::Response::RaiseErrors
+      builders << Faraday::Response::RaiseHttp5xx
       case Twitter.format.to_s
       when "json"
         builders << Faraday::Response::ParseJson
       when "xml"
         builders << Faraday::Response::ParseXml
       end
+      builders << Faraday::Response::RaiseHttp4xx
       builders << Faraday::Response::Mashify
       connection_with_builders(builders)
     end
 
     def connection_with_unparsed_response
       builders = []
-      builders << Faraday::Response::RaiseErrors
+      builders << Faraday::Response::RaiseHttp5xx
+      builders << Faraday::Response::RaiseHttp4xx
       connection_with_builders(builders)
     end
 

lib/twitter/geo.rb

@@ -127,13 +127,14 @@ def connection
       ssl = {:verify => false}
       @connection = Faraday::Connection.new(:url => @api_endpoint, :headers => headers, :ssl => ssl) do |builder|
         builder.adapter(@adapter || Faraday.default_adapter)
-        builder.use Faraday::Response::RaiseErrors
+        builder.use Faraday::Response::RaiseHttp5xx
         case Twitter.format.to_s
         when "json"
           builder.use Faraday::Response::ParseJson
         when "xml"
           builder.use Faraday::Response::ParseXml
         end
+        builder.use Faraday::Response::RaiseHttp4xx
         builder.use Faraday::Response::Mashify
       end
       @connection.scheme = Twitter.protocol

lib/twitter/search.rb

@@ -275,13 +275,14 @@ def connection
       ssl = {:verify => false}
       @connection = Faraday::Connection.new(:url => @api_endpoint.omit(:path), :headers => headers, :ssl => false) do |builder|
         builder.adapter(@adapter || Faraday.default_adapter)
-        builder.use Faraday::Response::RaiseErrors
+        builder.use Faraday::Response::RaiseHttp5xx
         case Twitter.format.to_s
         when "json"
           builder.use Faraday::Response::ParseJson
         when "xml"
           builder.use Faraday::Response::ParseXml
         end
+        builder.use Faraday::Response::RaiseHttp4xx
         builder.use Faraday::Response::Mashify
       end
       @connection.scheme = Twitter.protocol

lib/twitter/trends.rb

@@ -101,13 +101,14 @@ def connection
       ssl = {:verify => false}
       @connection = Faraday::Connection.new(:url => @api_endpoint, :headers => headers, :ssl => ssl) do |builder|
         builder.adapter(@adapter || Faraday.default_adapter)
-        builder.use Faraday::Response::RaiseErrors
+        builder.use Faraday::Response::RaiseHttp5xx
         case Twitter.format.to_s
         when "json"
           builder.use Faraday::Response::ParseJson
         when "xml"
           builder.use Faraday::Response::ParseXml
         end
+        builder.use Faraday::Response::RaiseHttp4xx
         builder.use Faraday::Response::Mashify
       end
       @connection.scheme = Twitter.protocol

lib/twitter/unauthenticated.rb

@@ -102,20 +102,22 @@ def list_timeline(list_owner_screen_name, slug, options = {})
 
     def connection
       builders = []
-      builders << Faraday::Response::RaiseErrors
+      builders << Faraday::Response::RaiseHttp5xx
       case Twitter.format.to_s
       when "json"
         builders << Faraday::Response::ParseJson
       when "xml"
         builders << Faraday::Response::ParseXml
       end
+      builders << Faraday::Response::RaiseHttp4xx
       builders << Faraday::Response::Mashify
       connection_with_builders(builders)
     end
 
     def connection_with_unparsed_response
       builders = []
-      builders << Faraday::Response::RaiseErrors
+      builders << Faraday::Response::RaiseHttp5xx
+      builders << Faraday::Response::RaiseHttp4xx
       connection_with_builders(builders)
     end