From 9141edfaa99d48ab8a1e0d81f1d6096f4db9c4ce Mon Sep 17 00:00:00 2001
From: Froidefond Julien <julienfroidefond@gmail.com>
Date: Fri, 6 Mar 2026 22:40:57 +0100
Subject: [PATCH] fix: handle SSE controller errors gracefully

- Add isActive checks before writing to SSE controller
- Wrap controller operations in try/catch to prevent 'already closed' errors
- Fix race condition when client disconnects during SSE streaming
---
 .../app/api/jobs/[id]/stream/route.ts         | 26 ++++++++++++++-----
 apps/backoffice/app/api/jobs/stream/route.ts  | 19 +++++++++-----
 2 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/apps/backoffice/app/api/jobs/[id]/stream/route.ts b/apps/backoffice/app/api/jobs/[id]/stream/route.ts
index d665350..45cd77a 100644
--- a/apps/backoffice/app/api/jobs/[id]/stream/route.ts
+++ b/apps/backoffice/app/api/jobs/[id]/stream/route.ts
@@ -33,26 +33,38 @@ export async function GET(
             },
           });
           
-          if (response.ok) {
+          if (response.ok && isActive) {
             const data = await response.json();
             const dataStr = JSON.stringify(data);
             
             // Only send if data changed
-            if (dataStr !== lastData) {
+            if (dataStr !== lastData && isActive) {
               lastData = dataStr;
-              controller.enqueue(
-                new TextEncoder().encode(`data: ${dataStr}\n\n`)
-              );
+              try {
+                controller.enqueue(
+                  new TextEncoder().encode(`data: ${dataStr}\n\n`)
+                );
+              } catch (err) {
+                // Controller closed, ignore
+                isActive = false;
+                return;
+              }
               
               // Stop polling if job is complete
               if (data.status === "success" || data.status === "failed" || data.status === "cancelled") {
                 isActive = false;
-                controller.close();
+                try {
+                  controller.close();
+                } catch (err) {
+                  // Already closed, ignore
+                }
               }
             }
           }
         } catch (error) {
-          console.error("SSE fetch error:", error);
+          if (isActive) {
+            console.error("SSE fetch error:", error);
+          }
         }
       };
       
diff --git a/apps/backoffice/app/api/jobs/stream/route.ts b/apps/backoffice/app/api/jobs/stream/route.ts
index ddf74b8..857f10b 100644
--- a/apps/backoffice/app/api/jobs/stream/route.ts
+++ b/apps/backoffice/app/api/jobs/stream/route.ts
@@ -28,20 +28,27 @@ export async function GET(request: NextRequest) {
             },
           });
           
-          if (response.ok) {
+          if (response.ok && isActive) {
             const data = await response.json();
             const dataStr = JSON.stringify(data);
             
             // Send if data changed
-            if (dataStr !== lastData) {
+            if (dataStr !== lastData && isActive) {
               lastData = dataStr;
-              controller.enqueue(
-                new TextEncoder().encode(`data: ${dataStr}\n\n`)
-              );
+              try {
+                controller.enqueue(
+                  new TextEncoder().encode(`data: ${dataStr}\n\n`)
+                );
+              } catch (err) {
+                // Controller closed, ignore
+                isActive = false;
+              }
             }
           }
         } catch (error) {
-          console.error("SSE fetch error:", error);
+          if (isActive) {
+            console.error("SSE fetch error:", error);
+          }
         }
       };