Do not alter the message in JSON encoder

If required, users can setup filters for that. We shouldnot assume any
overly specific use-cases here.

lib/rackstash/encoders/json.rb

@@ -9,24 +9,13 @@ require 'json'
 module Rackstash
   module Encoders
     # The JSON encoder formats the log event as a single-line JSON string. The
-    # resulting JSON string contains all data exposed by the buffer. Leading
-    # and trailing whitespace as well as any ANSI color codes in the `"message"`
-    # field will be removed.
-    #
-    # The resulting string is in the JSON format native to Logstash. You can
-    # thus ship your logs directly to Logstash without further processing by
-    # using Logstash's [json codec](https://www.elastic.co/guide/en/logstash/current/plugins-codecs-json.html)
-    # on the input definition.
+    # resulting JSON string contains all data exposed by the buffer.
     #
     # Most {Adapters} default to use this codec.
     class JSON
       # @param event [Hash] a log event as produced by the {Flow}
       # @return [String] the event as a single-line JSON string
       def encode(event)
-        event[FIELD_MESSAGE] = event[FIELD_MESSAGE]
-          .gsub(/\e\[[0-9;]*m/, EMPTY_STRING)
-          .strip
-
         ::JSON.dump(event)
       end
     end

lib/rackstash/encoders/logstash.rb

@@ -8,15 +8,13 @@ require 'rackstash/encoders/json'
 
 module Rackstash
   module Encoders
-    # The JSON encoder formats the log event as a single-line JSON string. The
-    # resulting JSON string contains all data exposed by the buffer. Leading
-    # and trailing whitespace as well as any ANSI color codes in the `"message"`
-    # field will be removed.
-    #
-    # The resulting string is in the JSON format native to Logstash. You can
-    # thus ship your logs directly to Logstash without further processing by
-    # using Logstash's [json codec](https://www.elastic.co/guide/en/logstash/current/plugins-codecs-json.html)
+    # The Logstash encoder formats the log event as a single-line JSON string in
+    # the JSON format native to Logstash. You can thus ship your logs directly
+    # to Logstash without further processing by using Logstash's
+    # [json codec](https://www.elastic.co/guide/en/logstash/current/plugins-codecs-json.html)
     # on the input definition.
+    #
+    # The resulting JSON string contains all data exposed by the buffer.
     class Logstash < JSON
       # @param event [Hash] a log event as produced by the {Flow}
       # @return [String] the event as a single-line JSON string

spec/rackstash/encoders/json_spec.rb

@@ -21,15 +21,5 @@ describe Rackstash::Encoders::JSON do
       event = { 'message' => "text\nwith\nnewlines" }
       expect(encoder.encode(event)).to eql '{"message":"text\nwith\nnewlines"}'
     end
-
-    it 'strips the message from all surrounding whitespace' do
-      event = { 'message' => "\n\t \nline1\nline2\n  \n\t\n" }
-      expect(encoder.encode(event)).to eql '{"message":"line1\nline2"}'
-    end
-
-    it 'removes any ANSI color codes from the message' do
-      event = { 'message' => "Important\n\e[31mRED TEXT\e[0m\nOK" }
-      expect(encoder.encode(event)).to eql '{"message":"Important\nRED TEXT\nOK"}'
-    end
   end
 end