From 06bd6d3dc7e8859fb6afd5744104a6f5358a6a95 Mon Sep 17 00:00:00 2001
From: Beth Skurrie <beth@bethesque.com>
Date: Mon, 29 Mar 2021 08:47:13 +1100
Subject: [PATCH] fix: handle metadata that has had its padding removed

---
 lib/pact_broker/api/pact_broker_urls.rb       | 33 +++++++++++++++----
 .../pact_broker/api/pact_broker_urls_spec.rb  | 16 +++++++--
 2 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/lib/pact_broker/api/pact_broker_urls.rb b/lib/pact_broker/api/pact_broker_urls.rb
index 4b9cffd4a..7fb87fcae 100644
--- a/lib/pact_broker/api/pact_broker_urls.rb
+++ b/lib/pact_broker/api/pact_broker_urls.rb
@@ -78,12 +78,7 @@ def encode_metadata(metadata)
 
       def decode_pact_metadata(metadata)
         if metadata && metadata != ''
-          begin
-            Rack::Utils.parse_nested_query(Base64.strict_decode64(metadata))
-          rescue StandardError => e
-            logger.warn("Exception parsing webhook metadata: #{metadata}", e)
-            {}
-          end
+          parse_nested_metadata_query(base64_decode_metadata(metadata))
         else
           {}
         end
@@ -385,6 +380,32 @@ def provider_name(thing)
           nil
         end
       end
+
+      def base64_decode_metadata(metadata)
+        Base64.strict_decode64(metadata)
+        # Some people remove the == padding on the end
+        rescue ArgumentError => e
+          logger.info("ArgumentError parsing webhook metadata: '#{metadata}'. Trying non strict decode.")
+          begin
+            Base64.decode64(metadata)
+          # Not sure that this can even happen, as invalid base64 chars are ignored
+          rescue StandardError => e
+            logger.warn("Exception parsing webhook metadata: '#{metadata}'", e)
+            ""
+          end
+        rescue StandardError => e
+          logger.warn("Exception parsing webhook metadata: '#{metadata}'", e)
+          ""
+      end
+
+      def parse_nested_metadata_query(query)
+        begin
+          Rack::Utils.parse_nested_query(query)
+        rescue StandardError => e
+          logger.warn("Could not parse query: '#{query}'", e)
+          {}
+        end
+      end
     end
   end
 end
diff --git a/spec/lib/pact_broker/api/pact_broker_urls_spec.rb b/spec/lib/pact_broker/api/pact_broker_urls_spec.rb
index b1feab59c..e987f3864 100644
--- a/spec/lib/pact_broker/api/pact_broker_urls_spec.rb
+++ b/spec/lib/pact_broker/api/pact_broker_urls_spec.rb
@@ -126,14 +126,24 @@ module Api
           end
         end
 
+        context "when the padding has been removed" do
+          let(:encoded_metadata) { Base64.strict_encode64("foo=bar").chomp("=") }
+
+          it "can still handle it" do
+            expect(PactBrokerUrls.decode_pact_metadata(encoded_metadata)).to eq("foo" => "bar")
+          end
+        end
+
         context "when the metadata is not valid base64" do
+          let(:encoded_metadata) { "%" }
+
           it "returns an empty hash" do
-            expect(PactBrokerUrls.decode_pact_metadata("foo==,")).to eq({})
+            expect(PactBrokerUrls.decode_pact_metadata(encoded_metadata)).to eq({})
           end
 
           it "logs a warning" do
-            expect(logger).to receive(:warn).with("Exception parsing webhook metadata: foo==,", ArgumentError)
-            PactBrokerUrls.decode_pact_metadata("foo==,")
+            expect(logger).to receive(:info).with("ArgumentError parsing webhook metadata: '%'. Trying non strict decode.")
+            PactBrokerUrls.decode_pact_metadata(encoded_metadata)
           end
         end
       end