Export helper for setting Nexus failure source on context (temporalio…

…#7286)

## What changed?
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## Why?
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## How did you test it?
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## Documentation
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common/nexus/failure.go

@@ -23,9 +23,11 @@
 package nexus
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"net/http"
+	"sync/atomic"
 
 	"github.com/nexus-rpc/sdk-go/nexus"
 	commonpb "go.temporal.io/api/common/v1"
@@ -48,6 +50,26 @@ type failureSourceContextKeyType struct{}
 
 var FailureSourceContextKey = failureSourceContextKeyType{}
 
+func SetFailureSourceOnContext(ctx context.Context, response *http.Response) {
+	if response == nil || response.Header == nil {
+		return
+	}
+
+	failureSourceHeader := response.Header.Get(FailureSourceHeaderName)
+	if failureSourceHeader == "" {
+		return
+	}
+
+	failureSourceContext := ctx.Value(FailureSourceContextKey)
+	if failureSourceContext == nil {
+		return
+	}
+
+	if val, ok := failureSourceContext.(*atomic.Value); ok {
+		val.Store(failureSourceHeader)
+	}
+}
+
 var failureTypeString = string((&failurepb.Failure{}).ProtoReflect().Descriptor().FullName())
 
 // ProtoFailureToNexusFailure converts a proto Nexus Failure to a Nexus SDK Failure.

components/nexusoperations/fx.go

@@ -26,7 +26,6 @@ import (
 	"context"
 	"fmt"
 	"net/http"
-	"sync/atomic"
 
 	"github.com/nexus-rpc/sdk-go/nexus"
 	"go.temporal.io/api/serviceerror"
@@ -140,7 +139,7 @@ func ClientProviderFactory(
 			httpCaller = func(r *http.Request) (*http.Response, error) {
 				r.Header.Set(NexusCallbackSourceHeader, clusterInfo.ClusterID)
 				resp, callErr := httpClient.Do(r)
-				setFailureSourceOnContext(ctx, resp)
+				commonnexus.SetFailureSourceOnContext(ctx, resp)
 				return resp, callErr
 			}
 		}
@@ -158,23 +157,3 @@ func ClientProviderFactory(
 func CallbackTokenGeneratorProvider() *commonnexus.CallbackTokenGenerator {
 	return commonnexus.NewCallbackTokenGenerator()
 }
-
-func setFailureSourceOnContext(ctx context.Context, response *http.Response) {
-	if response == nil || response.Header == nil {
-		return
-	}
-
-	failureSourceHeader := response.Header.Get(commonnexus.FailureSourceHeaderName)
-	if failureSourceHeader == "" {
-		return
-	}
-
-	failureSourceContext := ctx.Value(commonnexus.FailureSourceContextKey)
-	if failureSourceContext == nil {
-		return
-	}
-
-	if val, ok := failureSourceContext.(*atomic.Value); ok {
-		val.Store(failureSourceHeader)
-	}
-}