Validate record_custom_event type

CHANGELOG.md

@@ -13,6 +13,9 @@
 - **Breaking Change: Rename `bin/newrelic` command to `bin/newrelic_rpm`**
   The executable file for the agent's CLI has been renamed from `bin/newrelic` to `bin/newrelic_rpm`. This change resolves a name collision with the standalone New Relic CLI tool. [PR#3323](https://github.com/newrelic/newrelic-ruby-agent/pull/3323)
 
+- **Feature: Add argument validation for the `Agent#record_custom_event` API**
+  The `Agent#record_custom_event` API now raises an `ArgumentError` when an invalid `event_type` is provided. A valid event type must consist only of alphanumeric characters, underscores (`_`), colons (`:`), or spaces (` `). [PR#3319](https://github.com/newrelic/newrelic-ruby-agent/pull/3319)
+
 ## v9.23.0
 
 - **Feature: Add sidekiq.ignore_retry_errors configuration option**

lib/new_relic/agent.rb

@@ -117,6 +117,9 @@ class SerializationError < StandardError; end
     # been configured for
     AUTOMATIC_TRACER_MAX_ATTEMPTS = 60 # 60 = try about twice a second for 30 seconds
 
+    # Event types must consist of only alphanumeric characters, '_', ':', or ' '.
+    VALID_CUSTOM_EVENT_TYPE = /\A[\w: ]+\z/
+
     attr_reader :error_group_callback
     attr_reader :llm_token_count_callback
 
@@ -483,6 +486,10 @@ def set_error_group_callback(callback_proc)
     # @api public
     #
     def record_custom_event(event_type, event_attrs)
+      unless event_type.to_s.match?(VALID_CUSTOM_EVENT_TYPE)
+        raise ArgumentError, "Invalid event_type: '#{event_type}'. Event types must consist of only alphanumeric characters, '_', ':', or ' '."
+      end
+
       record_api_supportability_metric(:record_custom_event)
 
       if agent && NewRelic::Agent.config[:'custom_insights_events.enabled']

test/multiverse/suites/agent_only/custom_analytics_events_test.rb

@@ -36,13 +36,38 @@ def test_record_custom_event_returns_falsy_if_event_was_dropped
     refute(result)
   end
 
-  def test_record_doesnt_record_if_invalid_event_type
+  def test_record_custom_event_accepts_valid_event_types
+    NewRelic::Agent.record_custom_event('ValidEvent', {})
+    NewRelic::Agent.record_custom_event('valid_Event_underscore', {})
+    NewRelic::Agent.record_custom_event('Valid:Event:Colon', {})
+    NewRelic::Agent.record_custom_event('Valid Event Space', {})
+    NewRelic::Agent.record_custom_event('Valid123Event456Numbers', {})
+    NewRelic::Agent.record_custom_event('valideventlowercase', {})
+    NewRelic::Agent.record_custom_event(:ValidSymbol, {})
+    NewRelic::Agent.record_custom_event(:Valid_Symbol_Underscore, {})
+
+    NewRelic::Agent.agent.send(:harvest_and_send_custom_event_data)
+    events = last_posted_events
+
+    assert_equal(8, events.size)
+  end
+
+  def test_record_custom_event_raises_on_invalid_event_types
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event('', foo: :bar) }
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event('email@example.com', foo: :bar) }
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event('bang!', foo: :bar) }
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event('hyphen-ated', foo: :bar) }
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event('bad$news', foo: :bar) }
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event(nil, foo: :bar) }
+  end
+
+  def test_record_custom_event_skips_bad_event_types
     bad_event_type = 'bad$news'
     good_event_type = 'good news'
 
-    NewRelic::Agent.record_custom_event(bad_event_type, :foo => :bar)
-    NewRelic::Agent.record_custom_event(good_event_type, :foo => :bar)
+    assert_raises(ArgumentError) { NewRelic::Agent.record_custom_event(bad_event_type, foo: :bar) }
 
+    NewRelic::Agent.record_custom_event(good_event_type, :foo => :bar)
     NewRelic::Agent.agent.send(:harvest_and_send_custom_event_data)
     events = last_posted_events
 

test/new_relic/agent/llm/llm_event_test.rb

@@ -60,7 +60,8 @@ def test_event_attributes_adds_custom_attributes
 
     def test_record_does_not_create_an_event
       event = NewRelic::Agent::Llm::LlmEvent.new
-      event.record
+      assert_raises(ArgumentError) { event.record('', foo: :bar) }
+
       _, events = NewRelic::Agent.agent.custom_event_aggregator.harvest!
 
       assert_empty events