Make request to PoolRoute with empty SMC tier return error

Summary: As title Reviewed By: stuclar Differential Revision: D44887555 fbshipit-source-id: fd8f595fc3532b969df4681be35b96dc5999681a
facebook · May 3, 2023 · 0a402a5 · 0a402a5
1 parent 035dfed
commit 0a402a5
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Showing 3 changed files with 23 additions and 1 deletion.
diff --git a/mcrouter/routes/HashRouteFactory.h b/mcrouter/routes/HashRouteFactory.h
@@ -112,7 +112,19 @@ std::shared_ptr<typename RouterInfo::RouteHandleIf> createHashRoute(
 
   auto n = rh.size();
   if (n == 0) {
-    return createNullRoute<typename RouterInfo::RouteHandleIf>();
+    auto errorOnEmpty = true;
+    folly::StringPiece name{nullptr, nullptr};
+    if (json.isObject()) {
+      if (auto* jErrorOnEmpty = json.get_ptr("error_on_empty")) {
+        errorOnEmpty = parseBool(*jErrorOnEmpty, "error_on_empty");
+      }
+      if (auto* jName = json.get_ptr("name")) {
+        name = jName->stringPiece();
+      }
+    }
+    return errorOnEmpty ? createErrorRoute<RouterInfo>(folly::sformat(
+                              "HashRoute with empty children, name: {}", name))
+                        : createNullRoute<typename RouterInfo::RouteHandleIf>();
   }
   if (n == 1) {
     return std::move(rh[0]);

diff --git a/mcrouter/routes/McRouteHandleProvider-inl.h b/mcrouter/routes/McRouteHandleProvider-inl.h
@@ -626,6 +626,15 @@ McRouteHandleProvider<RouterInfo>::makePoolRoute(
         }
       }
     }
+
+    if (poolJson.json.isObject()) {
+      if (auto* jErrorOnEmpty = poolJson.json.get_ptr("error_on_empty")) {
+        jhashWithWeights["error_on_empty"] =
+            parseBool(*jErrorOnEmpty, "error_on_empty");
+      }
+    }
+    jhashWithWeights["name"] = poolJson.name;
+
     auto route = createHashRoute<RouterInfo>(
         jhashWithWeights, std::move(destinations), factory.getThreadId());
 

diff --git a/mcrouter/routes/test/Makefile.am b/mcrouter/routes/test/Makefile.am
@@ -11,6 +11,7 @@ mcrouter_routes_test_SOURCES = \
   ConstShardHashFuncTest.cpp \
   FailoverWithExptimeRouteTest.cpp \
   Main.cpp \
+  PoolRouteTest.cpp \
   RateLimitRouteTest.cpp \
   RouteHandleTestUtil.h \
   ShadowRouteTest.cpp \