Improve error log message output

Previously when an error were received by a Redis server, it was not
clear whether this came from a Redis Sentinel or a Redis server in the
cluster. This commit adds the hostname/port of the server to the
exception message via a log context.

Closes redis-rb#177

Author: stanhu

hiredis-client/lib/redis_client/hiredis_connection.rb

@@ -39,6 +39,8 @@ def initialize(ca_file: nil, ca_path: nil, cert: nil, key: nil, hostname: nil)
       end
     end
 
+    attr_reader :config
+
     def initialize(config, connect_timeout:, read_timeout:, write_timeout:)
       super()
       @config = config

lib/redis_client.rb

@@ -77,11 +77,26 @@ def timeout=(timeout)
     end
   end
 
-  Error = Class.new(StandardError)
+  module HasConfig
+    attr_reader :config
+
+    def _set_config(config)
+      @config = config
+    end
+
+    def to_s
+      return super unless config
+
+      "#{super} (#{config.server_url})"
+    end
+  end
+
+  class Error < StandardError
+    include HasConfig
+  end
 
   ProtocolError = Class.new(Error)
   UnsupportedServer = Class.new(Error)
-
   ConnectionError = Class.new(Error)
   CannotConnectError = Class.new(ConnectionError)
 
@@ -114,7 +129,7 @@ def parse(error_message)
         end
         code ||= error_message.split(' ', 2).first
         klass = ERRORS.fetch(code, self)
-        klass.new(error_message)
+        klass.new(error_message.strip)
       end
     end
   end

lib/redis_client/connection_mixin.rb

@@ -32,6 +32,7 @@ def call(command, timeout)
       @pending_reads -= 1
       if result.is_a?(Error)
         result._set_command(command)
+        result._set_config(config)
         raise result
       else
         result
@@ -53,10 +54,16 @@ def call_pipelined(commands, timeouts)
 
         # A multi/exec command can return an array of results.
         # An error from a multi/exec command is handled in Multi#_coerce!.
-        if result.is_a?(Error)
+        if result.is_a?(Array)
+          result.each do |res|
+            res._set_config(config) if res.is_a?(Error)
+          end
+        elsif result.is_a?(Error)
           result._set_command(commands[index])
+          result._set_config(config)
           exception ||= result
         end
+
         results[index] = result
       end
 

lib/redis_client/ruby_connection.rb

@@ -40,6 +40,8 @@ def ssl_context(ssl_params)
 
     SUPPORTS_RESOLV_TIMEOUT = Socket.method(:tcp).parameters.any? { |p| p.last == :resolv_timeout }
 
+    attr_reader :config
+
     def initialize(config, connect_timeout:, read_timeout:, write_timeout:)
       super()
       @config = config

test/redis_client_test.rb

@@ -64,6 +64,7 @@ def call_pipelined(commands, *)
       client.call("PING")
     end
     assert_includes error.message, "redis-client requires Redis 6+ with HELLO command available"
+    assert_includes error.message, "(redis://"
   end
 
   def test_redis_6_server_with_missing_hello_command
@@ -82,6 +83,7 @@ def call_pipelined(commands, *)
       client.call("PING")
     end
     assert_includes error.message, "redis-client requires Redis 6+ with HELLO command available"
+    assert_includes error.message, "(redis://"
   end
 
   def test_handle_async_raise

test/shared/redis_client_tests.rb

@@ -271,30 +271,30 @@ def test_wrong_type
       @redis.call("SISMEMBER", "str", "member")
     end
     assert_equal ["SISMEMBER", "str", "member"], error.command
-    assert_includes error.message, "WRONGTYPE Operation against a key holding the wrong kind of value"
+    assert_match(/WRONGTYPE Operation against a key holding the wrong kind of value (.*:.*)/, error.message)
 
     error = assert_raises RedisClient::CommandError do
       @redis.pipelined do |pipeline|
         pipeline.call("SISMEMBER", "str", "member")
       end
     end
     assert_equal ["SISMEMBER", "str", "member"], error.command
-    assert_includes error.message, "WRONGTYPE Operation against a key holding the wrong kind of value"
+    assert_match(/WRONGTYPE Operation against a key holding the wrong kind of value (.*:.*)/, error.message)
 
     error = assert_raises RedisClient::CommandError do
       @redis.multi do |transaction|
         transaction.call("SISMEMBER", "str", "member")
       end
     end
     assert_equal ["SISMEMBER", "str", "member"], error.command
-    assert_includes error.message, "WRONGTYPE Operation against a key holding the wrong kind of value"
+    assert_match(/WRONGTYPE Operation against a key holding the wrong kind of value (.*:.*)/, error.message)
   end
 
   def test_command_missing
     error = assert_raises RedisClient::CommandError do
       @redis.call("DOESNOTEXIST", "foo")
     end
-    assert_match(/ERR unknown command .DOESNOTEXIST./, error.message)
+    assert_match(/ERR unknown command .DOESNOTEXIST.*\(.*:.*\)/, error.message)
   end
 
   def test_authentication