In case of buffer overflow create an event with a slice of the data a…

…nd tag the event with an error

lib/logstash/codecs/json_lines.rb

@@ -69,6 +69,13 @@ def decode(data, &block)
     @buffer.extract(data).each do |line|
       parse_json(@converter.convert(line), &block)
     end
+  rescue java.lang.IllegalStateException => e
+    if e.message == "input buffer full" && @decode_size_limit_bytes != "none"
+      yield event_factory.new_event("message" => data[0..@decode_size_limit_bytes.to_i - 1], "tags" => ["_jsonparsetoobigfailure"]) #TODO check the failure tag
+    else
+      # re-raise the error if doesn't correspond to the buffer overflow condition
+      raise e
+    end
   end
 
   def encode(event)

spec/codecs/json_lines_spec.rb

@@ -132,7 +132,7 @@
 
         it "should raise an error if the max bytes are exceeded" do
           subject.decode(maximum_payload << "z") do |event|
-            expect(event.get("tags")).to include("_jsonparse_too_big_failure")
+            expect(event.get("tags")).to include("_jsonparsetoobigfailure")
             expect(event.get("message").size).to eq(decode_size_limit_bytes)
           end
         end