SERVER-18292 expose protocol type of RPC classes and

check that they match in runCommandWithMetadata

24 files changed, 111 insertions, 19 deletions

diff --git a/src/mongo/client/dbclient.cpp b/src/mongo/client/dbclient.cpp
index eca99e1614a..fc38fdb224e 100644
--- a/src/mongo/client/dbclient.cpp
+++ b/src/mongo/client/dbclient.cpp
@@ -280,6 +280,10 @@ namespace {
                                                                   StringData command,
                                                                   const BSONObj& metadata,
                                                                   const BSONObj& commandArgs) {
+        uassert(ErrorCodes::InvalidNamespace, str::stream() << "Database name '" << database
+                                                            << "' is not valid.",
+                NamespaceString::validDBName(database));
+
         BSONObjBuilder metadataBob;
         metadataBob.appendElements(metadata);
 
@@ -287,10 +291,6 @@ namespace {
             uassertStatusOK(_metadataWriter(&metadataBob));
         }
 
-        uassert(ErrorCodes::InvalidNamespace, str::stream() << "Database name '" << database
-                                                            << "' is not valid.",
-                NamespaceString::validDBName(database));
-
         auto requestBuilder = rpc::makeRequestBuilder(getClientRPCProtocols(),
                                                       getServerRPCProtocols());
 
@@ -313,9 +313,14 @@ namespace {
                               << "on host '" << host << "' ",
                 call(*requestMsg, *replyMsg, false, &host));
 
-        auto commandReply = rpc::makeReply(replyMsg.get(),
-                                           getClientRPCProtocols(),
-                                           getServerRPCProtocols());
+        auto commandReply = rpc::makeReply(replyMsg.get());
+
+        uassert(ErrorCodes::RPCProtocolNegotiationFailed,
+                      str::stream() << "Mismatched RPC protocols - request was '"
+                                    << opToString(requestMsg->operation()) << "' '"
+                                    << " but reply was '"
+                                    << opToString(replyMsg->operation()) << "' ",
+                requestBuilder->getProtocol() == commandReply->getProtocol());
 
         if (ErrorCodes::SendStaleConfig ==
             getStatusFromCommandResult(commandReply->getCommandReply())) {
diff --git a/src/mongo/rpc/command_reply.cpp b/src/mongo/rpc/command_reply.cpp
index 449308fbed3..7782b3b4997 100644
--- a/src/mongo/rpc/command_reply.cpp
+++ b/src/mongo/rpc/command_reply.cpp
@@ -71,6 +71,10 @@ namespace rpc {
         return  _outputDocs;
     }
 
+    Protocol CommandReply::getProtocol() const {
+        return rpc::Protocol::kOpCommandV1;
+    }
+
     bool operator==(const CommandReply& lhs, const CommandReply& rhs) {
         return std::tie(lhs._metadata, lhs._commandReply, lhs._outputDocs) ==
                std::tie(rhs._metadata, rhs._commandReply, rhs._outputDocs);
diff --git a/src/mongo/rpc/command_reply.h b/src/mongo/rpc/command_reply.h
index 8f888e6190d..73a3fe60ccf 100644
--- a/src/mongo/rpc/command_reply.h
+++ b/src/mongo/rpc/command_reply.h
@@ -80,6 +80,8 @@ namespace rpc {
          */
         DocumentRange getOutputDocs() const final;
 
+        Protocol getProtocol() const final;
+
         friend bool operator==(const CommandReply& lhs, const CommandReply& rhs);
         friend bool operator!=(const CommandReply& lhs, const CommandReply& rhs);
 
diff --git a/src/mongo/rpc/command_reply_builder.cpp b/src/mongo/rpc/command_reply_builder.cpp
index 09d4156e09f..e52eb750ede 100644
--- a/src/mongo/rpc/command_reply_builder.cpp
+++ b/src/mongo/rpc/command_reply_builder.cpp
@@ -77,6 +77,10 @@ namespace rpc {
         return _state;
     }
 
+    Protocol CommandReplyBuilder::getProtocol() const {
+        return rpc::Protocol::kOpCommandV1;
+    }
+
     std::unique_ptr<Message> CommandReplyBuilder::done() {
         invariant(_state == State::kOutputDocs);
         // TODO: we can elide a large copy here by transferring the internal buffer of
diff --git a/src/mongo/rpc/command_reply_builder.h b/src/mongo/rpc/command_reply_builder.h
index cf2cf01ee93..ec39986baba 100644
--- a/src/mongo/rpc/command_reply_builder.h
+++ b/src/mongo/rpc/command_reply_builder.h
@@ -33,6 +33,7 @@
 #include "mongo/base/status_with.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/rpc/document_range.h"
+#include "mongo/rpc/protocol.h"
 #include "mongo/rpc/reply_builder_interface.h"
 #include "mongo/util/net/message.h"
 
@@ -64,6 +65,10 @@ namespace rpc {
 
         State getState() const final;
 
+        Protocol getProtocol() const final;
+
+        void reset() final;
+
         /**
          * Writes data then transfers ownership of the message to the caller.
          * The behavior of calling any methods on the object is subsequently
diff --git a/src/mongo/rpc/command_request.cpp b/src/mongo/rpc/command_request.cpp
index 00a9fb7b477..f3006b73aa8 100644
--- a/src/mongo/rpc/command_request.cpp
+++ b/src/mongo/rpc/command_request.cpp
@@ -124,5 +124,9 @@ namespace rpc {
         return !(lhs == rhs);
     }
 
+    Protocol CommandRequest::getProtocol() const {
+        return rpc::Protocol::kOpCommandV1;
+    }
+
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/rpc/command_request.h b/src/mongo/rpc/command_request.h
index b96323477c2..cf2b54a7d42 100644
--- a/src/mongo/rpc/command_request.h
+++ b/src/mongo/rpc/command_request.h
@@ -31,6 +31,7 @@
 #include "mongo/base/string_data.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/rpc/document_range.h"
+#include "mongo/rpc/protocol.h"
 #include "mongo/rpc/request_interface.h"
 
 namespace mongo {
@@ -87,6 +88,8 @@ namespace rpc {
          */
         DocumentRange getInputDocs() const final;
 
+        Protocol getProtocol() const final;
+
         friend bool operator==(const CommandRequest& lhs, const CommandRequest& rhs);
         friend bool operator!=(const CommandRequest& lhs, const CommandRequest& rhs);
 
diff --git a/src/mongo/rpc/command_request_builder.cpp b/src/mongo/rpc/command_request_builder.cpp
index b65ddc3f0b3..b06fe47075d 100644
--- a/src/mongo/rpc/command_request_builder.cpp
+++ b/src/mongo/rpc/command_request_builder.cpp
@@ -94,6 +94,10 @@ namespace rpc {
         return _state;
     }
 
+    Protocol CommandRequestBuilder::getProtocol() const {
+        return rpc::Protocol::kOpCommandV1;
+    }
+
     std::unique_ptr<Message> CommandRequestBuilder::done() {
         invariant(_state == State::kInputDocs);
         // TODO: we can elide a large copy here by transferring the internal buffer of
diff --git a/src/mongo/rpc/command_request_builder.h b/src/mongo/rpc/command_request_builder.h
index 12298a48f3c..453b48f9cad 100644
--- a/src/mongo/rpc/command_request_builder.h
+++ b/src/mongo/rpc/command_request_builder.h
@@ -33,6 +33,7 @@
 #include "mongo/base/string_data.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/rpc/document_range.h"
+#include "mongo/rpc/protocol.h"
 #include "mongo/rpc/request_builder_interface.h"
 #include "mongo/util/net/message.h"
 
@@ -72,6 +73,8 @@ namespace rpc {
 
         State getState() const final;
 
+        Protocol getProtocol() const final;
+
         /**
          * Writes data then transfers ownership of the message to the caller.
          * The behavior of calling any methods on the object is subsequently
diff --git a/src/mongo/rpc/factory.cpp b/src/mongo/rpc/factory.cpp
index 1edca3950b3..81bcf42c969 100644
--- a/src/mongo/rpc/factory.cpp
+++ b/src/mongo/rpc/factory.cpp
@@ -37,6 +37,8 @@
 #include "mongo/rpc/protocol.h"
 #include "mongo/stdx/memory.h"
 #include "mongo/util/assert_util.h"
+#include "mongo/util/mongoutils/str.h"
+#include "mongo/util/net/message.h"
 
 namespace mongo {
 namespace rpc {
@@ -53,16 +55,17 @@ namespace rpc {
         }
     }
 
-    std::unique_ptr<ReplyInterface> makeReply(const Message* unownedMessage,
-                                              ProtocolSet clientProtos,
-                                              ProtocolSet serverProtos) {
-        switch (uassertStatusOK(negotiate(clientProtos, serverProtos))) {
-        case Protocol::kOpQuery:
+    std::unique_ptr<ReplyInterface> makeReply(const Message* unownedMessage) {
+
+        switch (unownedMessage->operation()) {
+        case mongo::opReply:
             return stdx::make_unique<LegacyReply>(unownedMessage);
-        case Protocol::kOpCommandV1:
+        case mongo::dbCommandReply:
             return stdx::make_unique<CommandReply>(unownedMessage);
         default:
-            MONGO_UNREACHABLE;
+            uasserted(ErrorCodes::UnsupportedFormat,
+                      str::stream() << "Received a reply message with unexpected opcode: "
+                                    << unownedMessage->operation());
         }
     }
 
diff --git a/src/mongo/rpc/factory.h b/src/mongo/rpc/factory.h
index 0e178a54ecb..93398d86e50 100644
--- a/src/mongo/rpc/factory.h
+++ b/src/mongo/rpc/factory.h
@@ -49,12 +49,12 @@ namespace rpc {
      */
     std::unique_ptr<RequestBuilderInterface> makeRequestBuilder(ProtocolSet clientProtos,
                                                                 ProtocolSet serverProtos);
+
     /**
-     * Returns the appropriate concrete Reply. Throws if one cannot be chosen.
+     * Returns the appropriate concrete Reply according to the contents of the message.
+     * Throws if one cannot be chosen.
      */
-    std::unique_ptr<ReplyInterface> makeReply(const Message* unownedMessage,
-                                              ProtocolSet clientProtos,
-                                              ProtocolSet serverProtos);
+    std::unique_ptr<ReplyInterface> makeReply(const Message* unownedMessage);
 
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/rpc/legacy_reply.cpp b/src/mongo/rpc/legacy_reply.cpp
index 31923818160..3c16df28426 100644
--- a/src/mongo/rpc/legacy_reply.cpp
+++ b/src/mongo/rpc/legacy_reply.cpp
@@ -83,5 +83,9 @@ namespace rpc {
         return DocumentRange{};
     }
 
+    Protocol LegacyReply::getProtocol() const {
+        return rpc::Protocol::kOpQuery;
+    }
+
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/rpc/legacy_reply.h b/src/mongo/rpc/legacy_reply.h
index f4182c1d3a0..e839d305b42 100644
--- a/src/mongo/rpc/legacy_reply.h
+++ b/src/mongo/rpc/legacy_reply.h
@@ -32,6 +32,7 @@
 #include "mongo/db/jsobj.h"
 #include "mongo/rpc/document_range.h"
 #include "mongo/rpc/reply_interface.h"
+#include "mongo/rpc/protocol.h"
 
 namespace mongo {
     class Message;
@@ -75,6 +76,8 @@ namespace rpc {
          */
         DocumentRange getOutputDocs() const final;
 
+        Protocol getProtocol() const final;
+
     private:
         const Message* _message;
 
diff --git a/src/mongo/rpc/legacy_reply_builder.cpp b/src/mongo/rpc/legacy_reply_builder.cpp
index 343e6874d4f..69134af3628 100644
--- a/src/mongo/rpc/legacy_reply_builder.cpp
+++ b/src/mongo/rpc/legacy_reply_builder.cpp
@@ -82,6 +82,10 @@ namespace rpc {
         return _state;
     }
 
+    Protocol LegacyReplyBuilder::getProtocol() const {
+        return rpc::Protocol::kOpQuery;
+    }
+
     std::unique_ptr<Message> LegacyReplyBuilder::done() {
         invariant(_state == State::kOutputDocs);
         std::unique_ptr<Message> message = stdx::make_unique<Message>();
diff --git a/src/mongo/rpc/legacy_reply_builder.h b/src/mongo/rpc/legacy_reply_builder.h
index cb8a52cae45..98dba8c8be5 100644
--- a/src/mongo/rpc/legacy_reply_builder.h
+++ b/src/mongo/rpc/legacy_reply_builder.h
@@ -33,6 +33,7 @@
 #include "mongo/base/status_with.h"
 #include "mongo/bson/util/builder.h"
 #include "mongo/rpc/document_range.h"
+#include "mongo/rpc/protocol.h"
 #include "mongo/rpc/reply_builder_interface.h"
 
 namespace mongo {
@@ -55,6 +56,8 @@ namespace rpc {
 
         std::unique_ptr<Message> done() final;
 
+        Protocol getProtocol() const final;
+
     private:
         BufBuilder _builder{};
         BSONObj _metadata{};
diff --git a/src/mongo/rpc/legacy_request.cpp b/src/mongo/rpc/legacy_request.cpp
index 459bc5f3d83..613cfe35ea1 100644
--- a/src/mongo/rpc/legacy_request.cpp
+++ b/src/mongo/rpc/legacy_request.cpp
@@ -74,5 +74,9 @@ namespace rpc {
         return DocumentRange{};
     }
 
+    Protocol LegacyRequest::getProtocol() const {
+        return rpc::Protocol::kOpQuery;
+    }
+
 }  // namespace rpc
 }  // namespace mongo
diff --git a/src/mongo/rpc/legacy_request.h b/src/mongo/rpc/legacy_request.h
index 93567a6fe6c..eb6df488e26 100644
--- a/src/mongo/rpc/legacy_request.h
+++ b/src/mongo/rpc/legacy_request.h
@@ -32,6 +32,7 @@
 #include "mongo/db/dbmessage.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/rpc/document_range.h"
+#include "mongo/rpc/protocol.h"
 #include "mongo/rpc/request_interface.h"
 
 namespace mongo {
@@ -87,6 +88,8 @@ namespace rpc {
          */
         DocumentRange getInputDocs() const final;
 
+        Protocol getProtocol() const final;
+
     private:
         const Message* _message;
         // TODO: metadata will be handled in SERVER-18236
diff --git a/src/mongo/rpc/legacy_request_builder.cpp b/src/mongo/rpc/legacy_request_builder.cpp
index 6997bf739ea..fc96d738905 100644
--- a/src/mongo/rpc/legacy_request_builder.cpp
+++ b/src/mongo/rpc/legacy_request_builder.cpp
@@ -110,6 +110,10 @@ namespace rpc {
         return _state;
     }
 
+    Protocol LegacyRequestBuilder::getProtocol() const {
+        return rpc::Protocol::kOpQuery;
+    }
+
     std::unique_ptr<Message> LegacyRequestBuilder::done() {
         invariant(_state == State::kInputDocs);
         _message->setData(dbQuery, _builder.buf(), _builder.len());
diff --git a/src/mongo/rpc/legacy_request_builder.h b/src/mongo/rpc/legacy_request_builder.h
index 0beed3b9a71..83890df45e2 100644
--- a/src/mongo/rpc/legacy_request_builder.h
+++ b/src/mongo/rpc/legacy_request_builder.h
@@ -56,6 +56,8 @@ namespace rpc {
 
         State getState() const final;
 
+        Protocol getProtocol() const final;
+
         std::unique_ptr<Message> done() final;
 
     private:
diff --git a/src/mongo/rpc/protocol.h b/src/mongo/rpc/protocol.h
index ba370a90e69..bb77caf5e85 100644
--- a/src/mongo/rpc/protocol.h
+++ b/src/mongo/rpc/protocol.h
@@ -83,7 +83,7 @@ namespace supports {
     /**
      * Converts a ProtocolSet to a string. Currently only the predefined ProtocolSets in the
      * 'supports' namespace are supported.
-     * 
+     *
      * This intentionally does not conform to the STL 'to_string' convention so that it will
      * not conflict with the to_string overload for uint64_t.
      */
diff --git a/src/mongo/rpc/reply_builder_interface.h b/src/mongo/rpc/reply_builder_interface.h
index 00942fe1dac..1abc04bba9e 100644
--- a/src/mongo/rpc/reply_builder_interface.h
+++ b/src/mongo/rpc/reply_builder_interface.h
@@ -32,6 +32,7 @@
 
 #include "mongo/base/disallow_copying.h"
 #include "mongo/base/status_with.h"
+#include "mongo/rpc/protocol.h"
 
 namespace mongo {
     class BSONObj;
@@ -112,6 +113,12 @@ namespace rpc {
         virtual State getState() const = 0;
 
         /**
+         * Gets the protocol used to serialize this reply. This should be used for validity checks
+         * only - runtime behavior changes should be implemented with polymorphism.
+         */
+        virtual Protocol getProtocol() const = 0;
+
+        /**
          * Writes data then transfers ownership of the message to the caller. The behavior of
          * calling any methods on the builder is subsequently undefined.
          */
diff --git a/src/mongo/rpc/reply_interface.h b/src/mongo/rpc/reply_interface.h
index 3fd5644f785..ac0514dc64f 100644
--- a/src/mongo/rpc/reply_interface.h
+++ b/src/mongo/rpc/reply_interface.h
@@ -29,6 +29,7 @@
 #pragma once
 
 #include "mongo/base/disallow_copying.h"
+#include "mongo/rpc/protocol.h"
 
 namespace mongo {
     class BSONObj;
@@ -68,6 +69,12 @@ namespace rpc {
          */
         virtual DocumentRange getOutputDocs() const = 0;
 
+        /**
+         * Gets the protocol used to deserialize this reply. This should be used for validity
+         * checks only - runtime behavior changes should be implemented with polymorphism.
+         */
+        virtual Protocol getProtocol() const = 0;
+
     protected:
         ReplyInterface() = default;
     };
diff --git a/src/mongo/rpc/request_builder_interface.h b/src/mongo/rpc/request_builder_interface.h
index 39623e12a10..7297bf393c5 100644
--- a/src/mongo/rpc/request_builder_interface.h
+++ b/src/mongo/rpc/request_builder_interface.h
@@ -31,6 +31,7 @@
 #include <memory>
 
 #include "mongo/base/disallow_copying.h"
+#include "mongo/rpc/protocol.h"
 
 namespace mongo {
     class Message;
@@ -104,6 +105,12 @@ namespace rpc {
         virtual State getState() const = 0;
 
         /**
+         * Gets the protocol used to serialize this request. This should only be used for asserts,
+         * and not for runtime behavior changes, which should be handled with polymorphism.
+         */
+        virtual Protocol getProtocol() const = 0;
+
+        /**
          * Writes data then transfers ownership of the message to the caller.
          * The behavior of calling any methods on the object is subsequently
          * undefined.
diff --git a/src/mongo/rpc/request_interface.h b/src/mongo/rpc/request_interface.h
index 27f407f3f5c..0933e728ab9 100644
--- a/src/mongo/rpc/request_interface.h
+++ b/src/mongo/rpc/request_interface.h
@@ -29,6 +29,7 @@
 #pragma once
 
 #include "mongo/base/disallow_copying.h"
+#include "mongo/rpc/protocol.h"
 
 namespace mongo {
     class BSONObj;
@@ -80,6 +81,12 @@ namespace rpc {
          */
         virtual DocumentRange getInputDocs() const = 0;
 
+        /**
+         * Gets the RPC protocol used to deserialize this message. This should only be used for
+         * asserts, and not for runtime behavior changes, which should be handled with polymorphism.
+         */
+        virtual Protocol getProtocol() const = 0;
+
     protected:
         RequestInterface() = default;
     };