More e2e coverage

Author: solnic

spec/features/tracing_spec.rb

@@ -16,7 +16,7 @@
     error_events = logged_events[:events].select { |event| event["exception"] }
     expect(error_events).not_to be_empty
 
-    error_event = error_events.first
+    error_event = error_events.last
     exception_values = error_event.dig("exception", "values")
     expect(exception_values).not_to be_empty
     expect(exception_values.first["type"]).to eq("ZeroDivisionError")
@@ -28,9 +28,13 @@
     expect(error_trace_id).to_not be(nil)
 
     if transaction_events.any?
-      transaction_event = transaction_events.first
-      trace_context = transaction_event.dig("contexts", "trace")
+      transaction_event = transaction_events.find do |event|
+        event.dig("contexts", "trace", "trace_id") == error_trace_id
+      end
 
+      expect(transaction_event).not_to be_nil, "No transaction event found with trace_id #{error_trace_id}"
+
+      trace_context = transaction_event.dig("contexts", "trace")
       expect(trace_context).not_to be_nil
 
       transaction_trace_id = trace_context["trace_id"]
@@ -59,4 +63,124 @@
       end
     end
   end
+
+  describe "propagated random value behavior" do
+    it "properly propagates and uses sample_rand for sampling decisions in backend transactions" do
+      visit "/error"
+
+      expect(page).to have_content("Svelte Mini App")
+      expect(page).to have_button("Trigger Error")
+
+      click_button "trigger-error-btn"
+
+      expect(page).to have_content("Error:")
+
+      expect(logged_events[:event_count]).to be > 0
+
+      transaction_events = logged_events[:events].select { |event| event["type"] == "transaction" }
+      expect(transaction_events).not_to be_empty
+
+      transactions = transaction_events.select { |event|
+        event.dig("contexts", "trace", "op") == "http.server"
+      }
+
+      expect(transactions).not_to be_empty, "Should have backend transactions"
+
+      transaction = transactions.first
+      expect(transaction).not_to be_nil
+
+      trace_context = transaction.dig("contexts", "trace")
+      expect(trace_context).not_to be_nil
+      expect(trace_context["trace_id"]).not_to be_nil
+
+      dsc = transaction.dig("_meta", "dsc")
+      if dsc && dsc["sample_rand"]
+        sample_rand = dsc["sample_rand"]
+
+        expect(sample_rand).to match(/^\d+\.\d{1,6}$/)
+
+        sample_rand_value = sample_rand.to_f
+        expect(sample_rand_value).to be >= 0.0
+        expect(sample_rand_value).to be < 1.0
+      end
+
+      logged_events[:envelopes].each do |envelope|
+        envelope["items"].each do |item|
+          next unless dsc = item.dig("payload", "_meta", "dsc")
+
+          sample_rand = dsc["sample_rand"]
+          expect(sample_rand).to match(/^\d+\.\d{1,6}$/)
+
+          sample_rand_value = sample_rand.to_f
+          expect(sample_rand_value).to be >= 0.0
+          expect(sample_rand_value).to be < 1.0
+
+          item["payload"]["spans"].each do |span|
+            sample_rand = span["data"]["sentry.sample_rand"]
+            expect(sample_rand).to be_a(Float)
+            expect(sample_rand).to be >= 0.0
+            expect(sample_rand).to be < 1.0
+          end
+        end
+      end
+    end
+
+    it "verifies sampling decisions are based on propagated sample_rand" do
+      visit "/error"
+
+      expect(page).to have_content("Svelte Mini App")
+      expect(page).to have_button("Trigger Error")
+
+      click_button "trigger-error-btn"
+
+      expect(page).to have_content("Error:")
+
+      transaction_events = logged_events[:events].select { |event| event["type"] == "transaction" }
+      expect(transaction_events).not_to be_empty
+
+      transaction_events.each do |transaction|
+        dsc = transaction.dig("_meta", "dsc")
+        next unless dsc && dsc["sample_rand"]
+
+        sample_rand = dsc["sample_rand"].to_f
+        sample_rate = dsc["sample_rate"]&.to_f
+
+          expected_sampled = sample_rand < sample_rate
+
+        expect(sample_rand).to be >= 0.0
+        expect(sample_rand).to be < 1.0
+        expect(sample_rate).to be > 0.0
+        expect(sample_rate).to be <= 1.0
+
+        expect(dsc["sample_rand"]).to match(/^\d+\.\d{1,6}$/)
+      end
+    end
+
+    it "maintains consistent sample_rand across multiple requests in the same trace" do
+      visit "/error"
+
+      expect(page).to have_content("Svelte Mini App")
+
+      3.times do |i|
+        click_button "trigger-error-btn"
+        sleep 0.1
+      end
+
+      expect(page).to have_content("Error:")
+
+      transaction_events = logged_events[:events].select { |event| event["type"] == "transaction" }
+      expect(transaction_events.length).to be >= 2
+
+      traces = transaction_events.group_by { |event| event.dig("contexts", "trace", "trace_id") }
+
+      traces.each do |trace_id, transactions|
+        next if transactions.length < 2
+
+        sample_rands = transactions.map { |transaction| transaction.dig("_meta", "dsc", "sample_rand") }.compact.uniq
+
+        expect(sample_rands.length).to eq(1),
+          "All transactions in trace #{trace_id} should have the same sample_rand, but found: #{sample_rands}"
+      end
+    end
+  end
 end

spec/support/test_helper.rb

@@ -16,7 +16,7 @@ def logged_events
           }
 
           event_data["items"].each do |item|
-            if item["headers"]["type"] == "event"
+            if ["event", "transaction"].include?(item["headers"]["type"])
               extracted_events << item["payload"]
             end
           end