Merge pull request stripe#10 from stripe/cory-send-exceptions

Ensure that errors sending to a UDP socket don't bubble up.

Gemfile

@@ -6,3 +6,7 @@ gemspec
 gem 'google-protobuf', '3.3.0'
 gem 'test-unit'
 gem 'rake'
+
+group :test do
+  gem 'mocha', '1.1.0'
+end

Gemfile.lock

@@ -1,13 +1,16 @@
 PATH
   remote: .
   specs:
-    ssf (0.0.7)
+    ssf (0.0.8)
       google-protobuf (= 3.3.0)
 
 GEM
   remote: https://rubygems.org/
   specs:
     google-protobuf (3.3.0)
+    metaclass (0.0.4)
+    mocha (1.1.0)
+      metaclass (~> 0.0.1)
     power_assert (1.0.2)
     rake (12.0.0)
     test-unit (3.2.4)
@@ -18,9 +21,10 @@ PLATFORMS
 
 DEPENDENCIES
   google-protobuf (= 3.3.0)
+  mocha (= 1.1.0)
   rake
   ssf!
   test-unit
 
 BUNDLED WITH
-   1.15.2
+   1.15.3

lib/ssf/client.rb

@@ -9,6 +9,7 @@ class Client
     attr_reader :port
 
     attr_reader :service
+    attr_reader :socket
 
     def initialize(host: DEFAULT_HOST, port: DEFAULT_PORT, service: '', max_buffer_size: 50)
       @host = host
@@ -26,7 +27,15 @@ def connect_to_socket(host, port)
     def send_to_socket(span)
       message = Ssf::SSFSpan.encode(span)
 
-      @socket.send(message, 0)
+      begin
+        # Despite UDP being connectionless, some implementations — including
+        # ruby — will throw an exception if there's nothing listening. We will
+        # rescue it to avoid any problems for our client.
+        @socket.send(message, 0)
+        true
+      rescue StandardError
+        false
+      end
     end
 
     def start_span(operation: '', tags: {}, parent: nil)

lib/ssf/local_buffering_client.rb

@@ -10,6 +10,7 @@ def initialize(service: '')
 
     def send_to_socket(span)
       @buffer << span
+      true
     end
 
     def reset

lib/ssf/logging_client.rb

@@ -7,6 +7,7 @@ def connect_to_socket(host, port)
 
     def send_to_socket(span)
       puts("would have sent #{span}")
+      true
     end
   end
 end

lib/ssf/ssf_methods.rb

@@ -17,7 +17,6 @@ def finish(time: nil)
       end
 
       @client.send_to_socket(self)
-      self
     end
 
     def child_span(operation: '', tags: {})

ssf-ruby.gemspec

@@ -1,6 +1,6 @@
 spec = Gem::Specification.new do |s|
   s.name = 'ssf'
-  s.version = '0.0.7'
+  s.version = '0.0.8'
   s.required_ruby_version = '>= 1.9.3'
   s.summary = 'Ruby client for the Standard Sensor Format'
   s.description = 'Ruby client for the Standard Sensor Format'

test/ssf/sample_test.rb

@@ -1,8 +1,20 @@
+require 'mocha/test_unit'
 require 'test/unit'
 require 'ssf'
 require 'securerandom'
 
 module SSFTest
+  class FailingClient < SSF::Client
+
+    def connect_to_socket(host, port)
+      nil
+    end
+
+    def send_to_socket(span)
+      false
+    end
+  end
+
   class SSFClientTest < Test::Unit::TestCase
     def test_create_ssf
       s = Ssf::SSFSpan.new({
@@ -75,13 +87,35 @@ def test_set_tag_with_nils
 
     end
 
+    def test_failing_client
+      c = FailingClient.new(host: '127.0.01', port: '8128')
+      span = c.start_span(operation: 'run test')
+      result = span.finish
+
+      assert_false(result, "Failing client didn't fail")
+    end
+
+    def test_failing_udp_client
+      UDPSocket.any_instance.stubs(:send).raises(StandardError.new("explosion"))
+
+      c = SSF::Client.new(host: '127.0.01', port: '8128')
+      STDERR.puts(c.socket)
+      # c.socket = stub()
+      # c.socket.stubs(:send)
+      span = c.start_span(operation: 'run test')
+      result = span.finish
+
+      assert_false(result, "Failing client didn't fail")
+    end
+
     def test_local_buffer_send
       s = Ssf::SSFSpan.new({
         id: 123456,
       })
 
       c = SSF::LocalBufferingClient.new()
-      c.send_to_socket(s)
+      result = c.send_to_socket(s)
+      assert_true(result, "Local client didn't return true")
 
       assert_equal(1, c.buffer.length, 'Expected to find one span in client')
       assert_equal(123456, c.buffer[0].id)
@@ -95,13 +129,15 @@ def test_client_send
       })
 
       c = SSF::LoggingClient.new(host: '127.0.01', port: '8128')
-      c.send_to_socket(s)
+      result = c.send_to_socket(s)
+      assert_true(result, "Logging client didn't return true")
     end
 
     def test_full_client_send
       c = SSF::LoggingClient.new(host: '127.0.01', port: '8128', service: 'test-srv')
       span = c.start_span(operation: 'run test')
-      span.finish
+      result = span.finish
+      assert_true(result, "Logging client didn't return true")
 
       assert(span.end_timestamp > span.start_timestamp)
       assert_equal('test_full_client_send(SSFTest::SSFClientTest)', name)