[Nexthop][fboss2-dev] Add config session rebase command for concurrent session conflict resolution

cmake/CliFboss2.cmake

@@ -766,6 +766,8 @@ add_library(fboss2_config_lib
   fboss/cli/fboss2/commands/config/session/CmdConfigSessionCommit.cpp
   fboss/cli/fboss2/commands/config/session/CmdConfigSessionDiff.h
   fboss/cli/fboss2/commands/config/session/CmdConfigSessionDiff.cpp
+  fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.h
+  fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.cpp
   fboss/cli/fboss2/session/ConfigSession.h
   fboss/cli/fboss2/session/ConfigSession.cpp
   fboss/cli/fboss2/session/Git.h

fboss/cli/fboss2/BUCK

@@ -931,6 +931,7 @@ cpp_library(
         "commands/config/rollback/CmdConfigRollback.cpp",
         "commands/config/session/CmdConfigSessionCommit.cpp",
         "commands/config/session/CmdConfigSessionDiff.cpp",
+        "commands/config/session/CmdConfigSessionRebase.cpp",
         "session/ConfigSession.cpp",
         "session/Git.cpp",
         "utils/InterfaceList.cpp",
@@ -992,6 +993,7 @@ cpp_library(
         "commands/config/rollback/CmdConfigRollback.h",
         "commands/config/session/CmdConfigSessionCommit.h",
         "commands/config/session/CmdConfigSessionDiff.h",
+        "commands/config/session/CmdConfigSessionRebase.h",
         "session/ConfigSession.h",
         "session/Git.h",
         "utils/InterfaceList.h",

fboss/cli/fboss2/CmdHandlerImplConfig.cpp

@@ -12,6 +12,7 @@
 
 // Current linter doesn't properly handle the template functions which need the
 // following headers
+// NOLINTBEGIN(misc-include-cleaner)
 // @lint-ignore-every CLANGTIDY facebook-unused-include-check
 #include "fboss/cli/fboss2/commands/config/CmdConfigAppliedInfo.h"
 #include "fboss/cli/fboss2/commands/config/CmdConfigReload.h"
@@ -85,6 +86,8 @@
 #include "fboss/cli/fboss2/commands/config/rollback/CmdConfigRollback.h"
 #include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionCommit.h"
 #include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionDiff.h"
+#include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.h"
+// NOLINTEND(misc-include-cleaner)
 
 namespace facebook::fboss {
 
@@ -112,6 +115,8 @@ template void
 CmdHandler<CmdConfigSessionCommit, CmdConfigSessionCommitTraits>::run();
 template void
 CmdHandler<CmdConfigSessionDiff, CmdConfigSessionDiffTraits>::run();
+template void
+CmdHandler<CmdConfigSessionRebase, CmdConfigSessionRebaseTraits>::run();
 template void CmdHandler<CmdConfigQos, CmdConfigQosTraits>::run();
 template void
 CmdHandler<CmdConfigQosBufferPool, CmdConfigQosBufferPoolTraits>::run();

fboss/cli/fboss2/CmdListConfig.cpp

@@ -83,6 +83,7 @@
 #include "fboss/cli/fboss2/commands/config/rollback/CmdConfigRollback.h"
 #include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionCommit.h"
 #include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionDiff.h"
+#include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.h"
 
 namespace facebook::fboss {
 
@@ -637,6 +638,12 @@ const CommandTree& kConfigCommandTree() {
                "Show diff between configs (session vs live, session vs revision, or revision vs revision)",
                commandHandler<CmdConfigSessionDiff>,
                argTypeHandler<CmdConfigSessionDiffTraits>,
+           },
+           {
+               "rebase",
+               "Rebase session changes onto current HEAD",
+               commandHandler<CmdConfigSessionRebase>,
+               argTypeHandler<CmdConfigSessionRebaseTraits>,
            }},
       },
 

fboss/cli/fboss2/cli_metadata.thrift

@@ -36,4 +36,7 @@ struct ConfigSessionMetadata {
   // List of CLI commands executed in this session, in chronological order.
   // Each entry is the full command string (e.g., "config interface eth1/1/1 mtu 9000").
   2: list<string> commands;
+  // Git commit SHA that this session is based on. Used to detect if someone
+  // else committed changes while this session was in progress.
+  3: string base;
 }

fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.cpp

@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2004-present, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+#include "fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.h"
+#include <iostream>
+#include <ostream>
+#include "fboss/cli/fboss2/session/ConfigSession.h"
+#include "fboss/cli/fboss2/utils/HostInfo.h"
+
+namespace facebook::fboss {
+
+CmdConfigSessionRebaseTraits::RetType CmdConfigSessionRebase::queryClient(
+    const HostInfo& /* hostInfo */) {
+  auto& session = ConfigSession::getInstance();
+  session.rebase(); // raises a runtime_error if we fail
+  return "Session successfully rebased onto current HEAD. You can now commit.";
+}
+
+void CmdConfigSessionRebase::printOutput(const RetType& logMsg) {
+  std::cout << logMsg << std::endl;
+}
+
+} // namespace facebook::fboss

fboss/cli/fboss2/commands/config/session/CmdConfigSessionRebase.h

@@ -0,0 +1,39 @@
+/*
+ *  Copyright (c) 2004-present, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+#pragma once
+
+#include <string>
+#include <variant>
+#include "fboss/cli/fboss2/CmdHandler.h"
+#include "fboss/cli/fboss2/utils/CmdUtilsCommon.h"
+#include "fboss/cli/fboss2/utils/HostInfo.h"
+
+namespace facebook::fboss {
+
+struct CmdConfigSessionRebaseTraits : public WriteCommandTraits {
+  static constexpr utils::ObjectArgTypeId ObjectArgTypeId =
+      utils::ObjectArgTypeId::OBJECT_ARG_TYPE_ID_NONE;
+  using ObjectArgType = std::monostate; // no arg
+  using RetType = std::string;
+};
+
+class CmdConfigSessionRebase
+    : public CmdHandler<CmdConfigSessionRebase, CmdConfigSessionRebaseTraits> {
+ public:
+  using ObjectArgType = CmdConfigSessionRebaseTraits::ObjectArgType;
+  using RetType = CmdConfigSessionRebaseTraits::RetType;
+
+  RetType queryClient(const HostInfo& hostInfo);
+
+  void printOutput(const RetType& logMsg);
+};
+
+} // namespace facebook::fboss