Improve error handling on missing config

The check is done closer to where the data is actually used.

Closes #76

Author: zimbatm

lib/pusher.rb

@@ -17,7 +17,11 @@ module Pusher
   #   end
   class Error < RuntimeError; end
   class AuthenticationError < Error; end
-  class ConfigurationError < Error; end
+  class ConfigurationError < Error
+    def initialize(key)
+      super "missing key `#{key}' in the client configuration"
+    end
+  end
   class HTTPError < Error; attr_accessor :original_error; end
 
   class << self

lib/pusher/client.rb

@@ -40,11 +40,14 @@ def initialize(options = {})
 
     # @private Returns the authentication token for the client
     def authentication_token
+      raise ConfigurationError, :key unless @key
+      raise ConfigurationError, :secret unless @secret
       Pusher::Signature::Token.new(@key, @secret)
     end
 
     # @private Builds a url for this app, optionally appending a path
     def url(path = nil)
+      raise ConfigurationError, :app_id unless @app_id
       URI::Generic.build({
         :scheme => @scheme,
         :host => @host,
@@ -186,7 +189,6 @@ def webhook(request)
     #   should not contain anything other than letters, numbers, or the
     #   characters "_\-=@,.;"
     def channel(channel_name)
-      raise ConfigurationError, 'Missing client configuration: please check that key, secret and app_id are configured.' unless configured?
       Channel.new(url, channel_name, self)
     end
 

spec/client_spec.rb

@@ -58,6 +58,13 @@
       it "should fail on bad urls" do
         expect { @client.url = "gopher/somekey:somesecret@://api.staging.pusherapp.co://m:8080\apps\87" }.to raise_error(URI::InvalidURIError)
       end
+
+      it "should raise exception if app_id is not configured" do
+        @client.app_id = nil
+        expect {
+          @client.url
+        }.to raise_error(Pusher::ConfigurationError)
+      end
     end
 
     describe 'configuring the cluster' do
@@ -116,13 +123,11 @@
           expect(@channel).to be_kind_of(Pusher::Channel)
         end
 
-        %w{app_id key secret}.each do |config|
-          it "should raise exception if #{config} not configured" do
-            @client.send("#{config}=", nil)
-            expect {
-              @client['test_channel']
-            }.to raise_error(Pusher::ConfigurationError)
-          end
+        it "should raise exception if app_id is not configured" do
+          @client.app_id = nil
+          expect {
+            @client['test_channel']
+          }.to raise_error(Pusher::ConfigurationError)
         end
       end