Merge #589

589: delayed_shutdown: Only broadcast `wall` messages if SSHSession is valid  r=ricab a=townsend2010

Fixes #539

Co-authored-by: Chris Townsend <[email protected]>

Author: bors[bot]

include/multipass/delayed_shutdown_timer.h

@@ -33,7 +33,7 @@ class DelayedShutdownTimer : public QObject
     Q_OBJECT
 
 public:
-    DelayedShutdownTimer(VirtualMachine* virtual_machine, SSHSession&& session);
+    DelayedShutdownTimer(VirtualMachine* virtual_machine, optional<SSHSession>&& session);
     ~DelayedShutdownTimer();
 
     void start(const std::chrono::milliseconds delay);
@@ -47,7 +47,7 @@ class DelayedShutdownTimer : public QObject
 
     QTimer shutdown_timer;
     VirtualMachine* virtual_machine;
-    SSHSession ssh_session;
+    optional<SSHSession> ssh_session;
     std::chrono::milliseconds delay;
     std::chrono::milliseconds time_remaining;
 };

include/multipass/optional.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2018 Canonical, Ltd.
+ * Copyright (C) 2018-2019 Canonical, Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -13,8 +13,6 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
- * Authored by: Alberto Aguirre <[email protected]>
- *
  */
 
 #ifndef MULTIPASS_OPTIONAL_H
@@ -25,17 +23,17 @@
 #include <optional>
 namespace multipass
 {
-using std::optional;
 using std::nullopt;
+using std::optional;
 }
 
 #elif __has_include(<experimental/optional>)
 
 #include <experimental/optional>
 namespace multipass
 {
-using std::experimental::optional;
 using std::experimental::nullopt;
+using std::experimental::optional;
 }
 
 #else

src/daemon/daemon.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017-2018 Canonical, Ltd.
+ * Copyright (C) 2017-2019 Canonical, Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -1972,7 +1972,17 @@ grpc::Status mp::Daemon::shutdown_vm(VirtualMachine& vm, const std::chrono::mill
     {
         delayed_shutdown_instances.erase(name);
 
-        mp::SSHSession session{vm.ssh_hostname(), vm.ssh_port(), vm.ssh_username(), *config->ssh_key_provider};
+        mp::optional<mp::SSHSession> session;
+        try
+        {
+            session = mp::SSHSession{vm.ssh_hostname(), vm.ssh_port(), vm.ssh_username(), *config->ssh_key_provider};
+        }
+        catch (const std::exception& e)
+        {
+            mpl::log(mpl::Level::info, category,
+                     fmt::format("Cannot open ssh session on \"{}\" shutdown: {}", name, e.what()));
+        }
+
         auto& shutdown_timer = delayed_shutdown_instances[name] =
             std::make_unique<DelayedShutdownTimer>(&vm, std::move(session));
 

src/daemon/delayed_shutdown_timer.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2018 Canonical, Ltd.
+ * Copyright (C) 2018-2019 Canonical, Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,22 +25,27 @@ namespace mpl = multipass::logging;
 
 namespace
 {
-void write_shutdown_message(mp::SSHSession& ssh_session, const std::chrono::minutes& time_left, const std::string& name)
+void write_shutdown_message(mp::optional<mp::SSHSession>& ssh_session, const std::chrono::minutes& time_left,
+                            const std::string& name)
 {
-    if (time_left > std::chrono::milliseconds::zero())
+    if (ssh_session)
     {
-        ssh_session.exec(fmt::format("wall \"The system is going down for poweroff in {} minute{}, use 'multipass stop "
-                                     "--cancel {}' to cancel the shutdown.\"",
-                                     time_left.count(), time_left > std::chrono::minutes(1) ? "s" : "", name));
-    }
-    else
-    {
-        ssh_session.exec(fmt::format("wall The system is going down for poweroff now"));
+        if (time_left > std::chrono::milliseconds::zero())
+        {
+            ssh_session->exec(
+                fmt::format("wall \"The system is going down for poweroff in {} minute{}, use 'multipass stop "
+                            "--cancel {}' to cancel the shutdown.\"",
+                            time_left.count(), time_left > std::chrono::minutes(1) ? "s" : "", name));
+        }
+        else
+        {
+            ssh_session->exec(fmt::format("wall The system is going down for poweroff now"));
+        }
     }
 }
 } // namespace
 
-mp::DelayedShutdownTimer::DelayedShutdownTimer(VirtualMachine* virtual_machine, SSHSession&& session)
+mp::DelayedShutdownTimer::DelayedShutdownTimer(VirtualMachine* virtual_machine, mp::optional<SSHSession>&& session)
     : virtual_machine{virtual_machine}, ssh_session{std::move(session)}
 {
 }
@@ -49,8 +54,11 @@ mp::DelayedShutdownTimer::~DelayedShutdownTimer()
 {
     if (shutdown_timer.isActive())
     {
-        // exit_code() is here to make sure the command finishes before continuing in the dtor
-        ssh_session.exec("wall The system shutdown has been cancelled").exit_code();
+        if (ssh_session)
+        {
+            // exit_code() is here to make sure the command finishes before continuing in the dtor
+            ssh_session->exec("wall The system shutdown has been cancelled").exit_code();
+        }
         mpl::log(mpl::Level::info, virtual_machine->vm_name, fmt::format("Cancelling delayed shutdown"));
         virtual_machine->state = VirtualMachine::State::running;
     }