From 235adaa4e78df9a9efd3ad97ca66613a708e0d6c Mon Sep 17 00:00:00 2001
From: Raghu Ram <raghuramg83@gmail.com>
Date: Mon, 3 Feb 2025 17:22:15 -0500
Subject: [PATCH] add exception handling for zlib compressed data errors

---
 lib/event_source/operations/mime_decode.rb    | 24 ++++++++-----------
 .../protocols/amqp/bunny_queue_proxy.rb       |  4 ----
 .../operations/mime_decode_spec.rb            | 13 ++++++++++
 .../protocols/amqp/bunny_queue_proxy_spec.rb  |  4 ----
 4 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/lib/event_source/operations/mime_decode.rb b/lib/event_source/operations/mime_decode.rb
index 1229169..3e99857 100644
--- a/lib/event_source/operations/mime_decode.rb
+++ b/lib/event_source/operations/mime_decode.rb
@@ -8,6 +8,7 @@ module Operations
     # Operation for decoding payloads, including decompression using Zlib.
     class MimeDecode
       include Dry::Monads[:result, :do]
+      include EventSource::Logging
 
       # Supported MIME types for decoding.
       MIME_TYPES = %w[application/zlib application/json].freeze
@@ -61,11 +62,15 @@ def validate_payload(payload, mime_type)
       # @return [Dry::Monads::Success<String>] if decoding is successful
       # @return [Dry::Monads::Failure<String>] if decoding fails
       def decode(payload, mime_type)
-        decoded_data = Zlib.inflate(payload) if mime_type == 'application/zlib' && binary_payload?(payload)
-
-        Success(decoded_data || payload)
-      rescue Zlib::Error => e
-        Failure("Failed to decode payload using Zlib: #{e.message}")
+        return Success(payload) unless mime_type == 'application/zlib'
+
+        begin
+          decoded_data = Zlib.inflate(payload)
+          Success(decoded_data)
+        rescue Zlib::Error => e
+          logger.error "Zlib errored while inflating payload: #{payload} \n with #{e.class}: #{e.message}, \n returning original payload."
+          Success(payload)
+        end
       end
 
       # Checks whether the payload is binary-encoded.
@@ -79,15 +84,6 @@ def binary_payload?(payload)
         payload.encoding == Encoding::BINARY
       end
 
-      # For future reference, here is the implementation of the `zlib_compressed?` method:
-      # Binary encoding check alone is unreliable since the payload may not be zlib-compressed.
-      # Instead, verify if the payload starts with "\x78" to determine zlib compression.
-      def zlib_compressed?(payload)
-        return false unless payload.is_a?(String)
-
-        payload.start_with?("\x78")
-      end
-
       def valid_json_string?(data)
         data.is_a?(String) && JSON.parse(data)
         true
diff --git a/lib/event_source/protocols/amqp/bunny_queue_proxy.rb b/lib/event_source/protocols/amqp/bunny_queue_proxy.rb
index 421c330..b4e9b52 100644
--- a/lib/event_source/protocols/amqp/bunny_queue_proxy.rb
+++ b/lib/event_source/protocols/amqp/bunny_queue_proxy.rb
@@ -180,10 +180,6 @@ def decode_payload(payload)
           if output.success?
             output.value!
           else
-            logger.error '*' * 40
-            logger.error payload.encoding if payload.respond_to?(:encoding)
-            logger.error payload.inspect
-            logger.error "Failed to decode message \n  due to: #{output.failure} \n  payload: #{payload}"
             raise EventSource::Error::PayloadDecodeError, output.failure
           end
         end
diff --git a/spec/event_source/operations/mime_decode_spec.rb b/spec/event_source/operations/mime_decode_spec.rb
index 17ddf62..7eaa084 100644
--- a/spec/event_source/operations/mime_decode_spec.rb
+++ b/spec/event_source/operations/mime_decode_spec.rb
@@ -93,6 +93,19 @@
           expect(result.failure).to eq("Payload must be binary-encoded for MIME type 'application/zlib'.")
         end
       end
+
+      context 'when Zlib.inflate raises an exception' do
+        let(:invalid_payload) { "NotCompressedData" }
+
+        it 'returns the original payload wrapped in Success' do
+          allow(Zlib).to receive(:inflate).and_raise(Zlib::DataError, "invalid compressed data")
+
+          result = subject.call('application/zlib', invalid_payload)
+
+          expect(result).to be_a(Dry::Monads::Success)
+          expect(result.value!).to eq(invalid_payload)
+        end
+      end
     end    
   end
 end
diff --git a/spec/event_source/protocols/amqp/bunny_queue_proxy_spec.rb b/spec/event_source/protocols/amqp/bunny_queue_proxy_spec.rb
index 213d438..0880f92 100644
--- a/spec/event_source/protocols/amqp/bunny_queue_proxy_spec.rb
+++ b/spec/event_source/protocols/amqp/bunny_queue_proxy_spec.rb
@@ -408,10 +408,6 @@
         end
 
         it 'logs the error and raises a PayloadDecodeError' do
-          expect(instance.logger).to receive(:error).with('*' * 40)
-          expect(instance.logger).to receive(:error).with(payload.encoding) if payload.respond_to?(:encoding)
-          expect(instance.logger).to receive(:error).with(payload.inspect)
-          expect(instance.logger).to receive(:error).with("Failed to decode message \n  due to: #{failure_message} \n  payload: #{payload}")
           expect do
             instance.decode_payload(payload)
           end.to raise_error(EventSource::Error::PayloadDecodeError, failure_message)