Implement close API that cleans up state and reverses init logic (#1844)

* Implement close API that cleans up state and reverses init logic

The only logic not reversed is `apply_patches` which is fine
since they already check if the patch is already applied
and also no-op if `initialized?` is false.

* Specs

* Fix Tracepoint test

* Remove no-ops and fix tracepoint receive

* changelog

* Fix changelog

* Call close on at_exit

CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ### Features
 
+- Expose `:values` in `ExceptionInterface`, so that it can be accessed in `before_send` under `event.exception.values` [#1843](https://github.com/getsentry/sentry-ruby/pull/1843)
+
+- Add top level `Sentry.close` API [#1844](https://github.com/getsentry/sentry-ruby/pull/1844)
+  - Cleans up SDK state and sets it to uninitialized
+  - No-ops all SDK APIs and also disables the transport layer, so nothing will be sent to Sentry after closing the SDK
+
 - Handle exception with large stacktrace without dropping entire item [#1807](https://github.com/getsentry/sentry-ruby/pull/1807)
 - Capture Rails runner's exceptions before exiting [#1820](https://github.com/getsentry/sentry-ruby/pull/1820)
 

sentry-ruby/lib/sentry-ruby.rb

@@ -60,11 +60,11 @@ def exception_locals_tp
     end
 
     # @!attribute [rw] background_worker
-    #   @return [BackgroundWorker]
+    #   @return [BackgroundWorker, nil]
     attr_accessor :background_worker
 
     # @!attribute [r] session_flusher
-    #   @return [SessionFlusher]
+    #   @return [SessionFlusher, nil]
     attr_reader :session_flusher
 
     ##### Patch Registration #####
@@ -213,10 +213,30 @@ def init(&block)
         exception_locals_tp.enable
       end
 
-      at_exit do
-        @session_flusher&.kill
+      at_exit { close }
+    end
+
+    # Flushes pending events and cleans up SDK state.
+    # SDK will stop sending events and all top-level APIs will be no-ops after this.
+    #
+    # @return [void]
+    def close
+      if @background_worker
         @background_worker.shutdown
+        @background_worker = nil
+      end
+
+      if @session_flusher
+        @session_flusher.kill
+        @session_flusher = nil
+      end
+
+      if configuration&.capture_exception_frame_locals
+        exception_locals_tp.disable
       end
+
+      @main_hub = nil
+      Thread.current.thread_variable_set(THREAD_LOCAL, nil)
     end
 
     # Returns true if the SDK is initialized.
@@ -287,6 +307,7 @@ def get_current_scope
     #
     # @return [void]
     def clone_hub_to_current_thread
+      return unless initialized?
       Thread.current.thread_variable_set(THREAD_LOCAL, get_main_hub.clone)
     end
 

sentry-ruby/spec/sentry_spec.rb

@@ -784,4 +784,71 @@
     end
   end
 
+  describe ".close" do
+    context "when closing initialized SDK" do
+      it "not initialized?" do
+        expect(described_class.initialized?).to eq(true)
+        described_class.close
+        expect(described_class.initialized?).to eq(false)
+      end
+
+      it "removes main hub" do
+        expect(described_class.get_main_hub).to be_a(Sentry::Hub)
+        described_class.close
+        expect(described_class.get_main_hub).to eq(nil)
+      end
+
+      it "removes thread local" do
+        expect(Thread.current.thread_variable_get(described_class::THREAD_LOCAL)).to be_a(Sentry::Hub)
+        described_class.close
+        expect(Thread.current.thread_variable_get(described_class::THREAD_LOCAL)).to eq(nil)
+
+      end
+
+      it "calls background worker shutdown" do
+        expect(described_class.background_worker).to receive(:shutdown)
+        described_class.close
+        expect(described_class.background_worker).to eq(nil)
+      end
+
+      it "kills session flusher" do
+        expect(described_class.session_flusher).to receive(:kill)
+        described_class.close
+        expect(described_class.session_flusher).to eq(nil)
+      end
+
+      it "disables Tracepoint" do
+        perform_basic_setup do |config|
+          config.capture_exception_frame_locals = true
+        end
+
+        expect(described_class.exception_locals_tp).to receive(:disable).and_call_original
+        described_class.close
+      end
+    end
+
+    it "can reinitialize closed SDK" do
+      perform_basic_setup
+
+      expect do
+        described_class.capture_event(event)
+      end.to change { transport.events.count }.by(1)
+
+      described_class.close
+
+      expect do
+        described_class.capture_event(event)
+      end.to change { transport.events.count }.by(0)
+
+      perform_basic_setup
+
+      expect(described_class.initialized?).to eq(true)
+
+      new_transport = described_class.get_current_client.transport
+
+      expect do
+        described_class.capture_event(event)
+      end.to change { new_transport.events.count }.by(1)
+    end
+  end
 end