From c23b0c64bd707e9b492eafecdecf446b25c9615f Mon Sep 17 00:00:00 2001
From: Yu Yi <yiyu@google.com>
Date: Thu, 28 May 2026 19:56:52 +0000
Subject: [PATCH] Harden event log writes

---
 event-exporter/sinks/stackdriver/writer.go    |  7 +-
 .../sinks/stackdriver/writer_test.go          | 92 +++++++++++++++++++
 2 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 event-exporter/sinks/stackdriver/writer_test.go

diff --git a/event-exporter/sinks/stackdriver/writer.go b/event-exporter/sinks/stackdriver/writer.go
index 0d11b3084..15d71055f 100644
--- a/event-exporter/sinks/stackdriver/writer.go
+++ b/event-exporter/sinks/stackdriver/writer.go
@@ -48,9 +48,10 @@ func newSdWriter(service *sd.Service) sdWriter {
 // unless the API returns BadRequest error.
 func (w sdWriterImpl) Write(entries []*sd.LogEntry, logName string, resource *sd.MonitoredResource) {
 	req := &sd.WriteLogEntriesRequest{
-		Entries:  entries,
-		LogName:  logName,
-		Resource: resource,
+		Entries:        entries,
+		LogName:        logName,
+		PartialSuccess: true,
+		Resource:       resource,
 	}
 
 	// We retry forever, until request either succeeds or API returns
diff --git a/event-exporter/sinks/stackdriver/writer_test.go b/event-exporter/sinks/stackdriver/writer_test.go
new file mode 100644
index 000000000..9f589fb3e
--- /dev/null
+++ b/event-exporter/sinks/stackdriver/writer_test.go
@@ -0,0 +1,92 @@
+/*
+Copyright 2026 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package stackdriver
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	sd "google.golang.org/api/logging/v2"
+)
+
+func TestWriterEnablesPartialSuccess(t *testing.T) {
+	type writeRequest struct {
+		method string
+		path   string
+		body   *sd.WriteLogEntriesRequest
+		err    error
+	}
+
+	requests := make(chan writeRequest, 1)
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		defer r.Body.Close()
+
+		var req sd.WriteLogEntriesRequest
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			requests <- writeRequest{
+				method: r.Method,
+				path:   r.URL.Path,
+				err:    fmt.Errorf("decode request body: %w", err),
+			}
+		} else {
+			requests <- writeRequest{
+				method: r.Method,
+				path:   r.URL.Path,
+				body:   &req,
+			}
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`{}`))
+	}))
+	defer server.Close()
+
+	service, err := sd.New(server.Client())
+	if err != nil {
+		t.Fatalf("New logging service: %v", err)
+	}
+	service.BasePath = server.URL + "/"
+
+	writer := sdWriterImpl{service: service}
+	writer.Write(
+		[]*sd.LogEntry{{TextPayload: "entry"}},
+		"projects/test-project/logs/events",
+		&sd.MonitoredResource{Type: k8sCluster},
+	)
+
+	select {
+	case req := <-requests:
+		if req.err != nil {
+			t.Fatal(req.err)
+		}
+		if req.path != "/v2/entries:write" {
+			t.Fatalf("request path = %q, want %q", req.path, "/v2/entries:write")
+		}
+		if req.method != http.MethodPost {
+			t.Fatalf("request method = %q, want %q", req.method, http.MethodPost)
+		}
+		if !req.body.PartialSuccess {
+			t.Fatal("PartialSuccess = false, want true")
+		}
+	case <-time.After(1 * time.Second):
+		t.Fatal("timed out waiting for write request")
+	}
+}