fix(error-tracking): Accept empty transaction string in sentry payload

Fixes #353153

app/services/error_tracking/collect_error_service.rb

@@ -60,7 +60,7 @@ module ErrorTracking
     end
 
     def actor
-      return event['transaction'] if event['transaction']
+      return event['transaction'] if event['transaction'].present?
 
       # Some SDKs do not have a transaction attribute.
       # So we build it by combining function name and module name from

spec/fixtures/error_tracking/php_empty_transaction.json

+{
+  "event_id": "dquJXuPF9sP1fMy5RpKo979xUALjNDQB",
+  "timestamp": 1645191605.123456,
+  "platform": "php",
+  "sdk": {
+    "name": "sentry.php",
+    "version": "3.3.7"
+  },
+  "logger": "php",
+  "transaction": "",
+  "server_name": "oAjA5zTgIjqP",
+  "release": "C0FFEE",
+  "environment": "Development/Berlin",
+  "exception": {
+    "values": [
+      {
+        "type": "TestException",
+        "value": "Sentry test exception",
+        "stacktrace": {
+          "frames": [
+            {
+              "filename": "/src/Path/To/Class.php",
+              "lineno": 3,
+              "in_app": true,
+              "abs_path": "/var/www/html/src/Path/To/Class.php",
+              "function": "Path\\To\\Class::method",
+              "raw_function": "Path\\To\\Class::method",
+              "pre_context": [
+                "// Pre-context"
+              ],
+              "context_line": "throw new TestException('Sentry test exception');",
+              "post_context": [
+                "// Post-context"
+              ]
+            }
+          ]
+        },
+        "mechanism": {
+          "type": "generic",
+          "handled": true
+        }
+      }
+    ]
+  }
+}

spec/requests/api/error_tracking/collector_spec.rb

@@ -171,6 +171,12 @@ RSpec.describe API::ErrorTracking::Collector do
       it_behaves_like 'successful request'
     end
 
+    context 'when JSON key transaction is empty string' do
+      let_it_be(:raw_event) { fixture_file('error_tracking/php_empty_transaction.json') }
+
+      it_behaves_like 'successful request'
+    end
+
     context 'sentry_key as param and empty headers' do
       let(:url) { "/error_tracking/collector/api/#{project.id}/store?sentry_key=#{sentry_key}" }
       let(:headers) { {} }

spec/services/error_tracking/collect_error_service_spec.rb

@@ -51,25 +51,30 @@ RSpec.describe ErrorTracking::CollectErrorService do
       end
     end
 
-    context 'unusual payload' do
+    context 'with unusual payload' do
       let(:modified_event) { parsed_event }
+      let(:event) { described_class.new(project, nil, event: modified_event).execute }
 
-      context 'missing transaction' do
+      context 'when transaction is missing' do
         it 'builds actor from stacktrace' do
           modified_event.delete('transaction')
 
-          event = described_class.new(project, nil, event: modified_event).execute
+          expect(event.error.actor).to eq 'find()'
+        end
+      end
+
+      context 'when transaction is an empty string' do \
+        it 'builds actor from stacktrace' do
+          modified_event['transaction'] = ''
 
           expect(event.error.actor).to eq 'find()'
         end
       end
 
-      context 'timestamp is numeric' do
+      context 'when timestamp is numeric' do
         it 'parses timestamp' do
           modified_event['timestamp'] = '1631015580.50'
 
-          event = described_class.new(project, nil, event: modified_event).execute
-
           expect(event.occurred_at).to eq '2021-09-07T11:53:00.5'
         end
       end