Update frame truncating to keep first & last N/2 frames instead of ju…

…st last N frames
getsentry · May 10, 2022 · 4e48130 · 4e48130
1 parent 1b39151
commit 4e48130
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Showing 2 changed files with 27 additions and 4 deletions.
diff --git a/sentry-ruby/lib/sentry/transport.rb b/sentry-ruby/lib/sentry/transport.rb
@@ -88,14 +88,20 @@ def serialize_envelope(envelope)
             single_exceptions.each do |single_exception|
               traces = single_exception.dig(:stacktrace, :frames)
               if traces && traces.size > STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD
-                traces.replace(traces[-STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD..-1])
+                size_on_both_ends = STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD / 2
+                traces.replace(
+                  traces[0..(size_on_both_ends - 1)] + traces[-size_on_both_ends..-1],
+                )
               end
             end
           elsif single_exceptions = item.payload.dig("exception", "values")
             single_exceptions.each do |single_exception|
               traces = single_exception.dig("stacktrace", "frames")
               if traces && traces.size > STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD
-                traces.replace(traces[-STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD..-1])
+                size_on_both_ends = STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD / 2
+                traces.replace(
+                  traces[0..(size_on_both_ends - 1)] + traces[-size_on_both_ends..-1],
+                )
               end
             end
           end

diff --git a/sentry-ruby/spec/sentry/transport_spec.rb b/sentry-ruby/spec/sentry/transport_spec.rb
@@ -147,7 +147,8 @@
           project_root = "/fake/project_root"
           Regexp.new("^(#{project_root}/)?#{Sentry::Backtrace::APP_DIRS_PATTERN}")
         end
-        let(:frame_list_size) { Sentry::Transport::STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD * 4 }
+        let(:frame_list_limit) { Sentry::Transport::STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD }
+        let(:frame_list_size) { frame_list_limit * 4 }
 
         before do
           single_exception = event.exception.instance_variable_get(:@values)[0]
@@ -173,10 +174,26 @@
 
           event_item = envelope.items.first
           frames = event_item.payload[:exception][:values][0][:stacktrace][:frames]
-          expect(frames.length).to eq(Sentry::Transport::STACKTRACE_FRAME_LIMIT_ON_OVERSIZED_PAYLOAD)
+          expect(frames.length).to eq(frame_list_limit)
+
+          # Last N lines kept
+          # N = Frame limit / 2
           expect(frames[-1][:lineno]).to eq(frame_list_size)
           expect(frames[-1][:filename]).to eq('app.rb')
           expect(frames[-1][:function]).to eq('/')
+          #
+          expect(frames[-(frame_list_limit / 2)][:lineno]).to eq(frame_list_size - ((frame_list_limit / 2) - 1))
+          expect(frames[-(frame_list_limit / 2)][:filename]).to eq('app.rb')
+          expect(frames[-(frame_list_limit / 2)][:function]).to eq('/')
+
+          # First N lines kept
+          # N = Frame limit / 2
+          expect(frames[0][:lineno]).to eq(1)
+          expect(frames[0][:filename]).to eq('app.rb')
+          expect(frames[0][:function]).to eq('/')
+          expect(frames[(frame_list_limit / 2) - 1][:lineno]).to eq(frame_list_limit / 2)
+          expect(frames[(frame_list_limit / 2) - 1][:filename]).to eq('app.rb')
+          expect(frames[(frame_list_limit / 2) - 1][:function]).to eq('/')
         end
 
         context "if it's still oversized" do