From cb9286c98963ef3b246441ea007b77b064e343d9 Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf@users.noreply.github.com>
Date: Wed, 28 Jan 2026 15:32:46 +0100
Subject: [PATCH] DPL: disable early forwarding for output proxies

---
 Framework/Core/src/DataProcessingDevice.cxx      | 9 +++++++++
 Framework/Core/src/ExternalFairMQDeviceProxy.cxx | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/Framework/Core/src/DataProcessingDevice.cxx b/Framework/Core/src/DataProcessingDevice.cxx
index 3eaab36fb7908..fd03b7725d847 100644
--- a/Framework/Core/src/DataProcessingDevice.cxx
+++ b/Framework/Core/src/DataProcessingDevice.cxx
@@ -1070,6 +1070,15 @@ void DataProcessingDevice::fillContext(DataProcessorContext& context, DeviceCont
         break;
       }
     }
+    // Output proxies should wait for the completion policy before forwarding.
+    // Because they actually do not do anything, that's equivalent to
+    // forwarding after the processing.
+    for (auto& label : spec.labels) {
+      if (label.value == "output-proxy") {
+        defaultEarlyForwardPolicy = ForwardPolicy::AfterProcessing;
+        break;
+      }
+    }
 
     /// We must make sure there is no optional
     /// if we want to optimize the forwarding
diff --git a/Framework/Core/src/ExternalFairMQDeviceProxy.cxx b/Framework/Core/src/ExternalFairMQDeviceProxy.cxx
index b4bfc991db9ae..3b0275879a158 100644
--- a/Framework/Core/src/ExternalFairMQDeviceProxy.cxx
+++ b/Framework/Core/src/ExternalFairMQDeviceProxy.cxx
@@ -1045,6 +1045,7 @@ DataProcessorSpec specifyFairMQDeviceOutputProxy(char const* name,
   spec.options = {
     ConfigParamSpec{"channel-config", VariantType::String, d, {"Out-of-band channel config"}},
   };
+  spec.labels.push_back(DataProcessorLabel{"output-proxy"});
 
   return spec;
 }
@@ -1180,6 +1181,7 @@ DataProcessorSpec specifyFairMQDeviceMultiOutputProxy(char const* name,
   spec.options = {
     ConfigParamSpec{"channel-config", VariantType::String, d, {"Out-of-band channel config"}},
   };
+  spec.labels.push_back(DataProcessorLabel{"output-proxy"});
 
   return spec;
 }