Merge lp:~thomas-voss/location-service/fix-1415029 into lp:location-service/trunk

[Thomas Voß]

Make remote provider initialization robust against services not being available during initialization.

Make remote provider initialization robust against services not being available during initialization.

[lp:~thomas-voss/location-service/fix-1415029]

167. By Thomas Voß on 2015-01-27

Add comments explaining the ctor arguments.

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:167
http://jenkins.qa.ubuntu.com/job/location-service-ci/345/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/location-service-vivid-amd64-ci/17
    SUCCESS: http://jenkins.qa.ubuntu.com/job/location-service-vivid-armhf-ci/17
        deb: http://jenkins.qa.ubuntu.com/job/location-service-vivid-armhf-ci/17/artifact/work/output/*zip*/output.zip
    SUCCESS: http://jenkins.qa.ubuntu.com/job/location-service-vivid-i386-ci/17

Click here to trigger a rebuild:
http://s-jenkins.ubuntu-ci:8080/job/location-service-ci/345/rebuild

review: Approve (continuous-integration)

Unmerged revisions

167. By Thomas Voß on 2015-01-27

Add comments explaining the ctor arguments.

166. By Thomas Voß on 2015-01-27

Make remote provider initialization robust against services not being available during initialization.

=== modified file 'src/location_service/com/ubuntu/location/providers/remote/provider.cpp'
--- src/location_service/com/ubuntu/location/providers/remote/provider.cpp	2015-01-26 19:13:52 +0000
+++ src/location_service/com/ubuntu/location/providers/remote/provider.cpp	2015-01-27 14:28:08 +0000
@@ -22,7 +22,9 @@
 
 #include <com/ubuntu/location/logging.h>
 
+#include <core/dbus/dbus.h>
 #include <core/dbus/object.h>
+#include <core/dbus/service_watcher.h>
 #include <core/dbus/signal.h>
 #include <core/dbus/asio/executor.h>
 
@@ -39,6 +41,101 @@
 
 namespace
 {
+// NotYet is a provider decoration that waits for a remote service to come up, before instantiating
+// the actual stub instance.
+class NotYet : public cul::Provider
+{
+public:
+    // Creates a new instance, watching fo the given service_name on the given bus, invoking the
+    // when_ready functor for constructing the provider instance whenever the service becomes ready.
+    NotYet(const core::dbus::Bus::Ptr& bus, const std::string& service_name, const std::function<cul::Provider::Ptr()>& when_ready)
+        : dbus{bus}, service_watcher{dbus.make_service_watcher(service_name)},
+          service_registered
+          {
+              service_watcher->service_registered().connect([this, when_ready]()
+              {
+                  impl = when_ready();
+              })
+          }
+    {
+    }
+
+    bool matches_criteria(const cul::Criteria& criteria) override
+    {
+        if (impl) return impl->matches_criteria(criteria);
+
+        return false;
+    }
+
+    bool supports(const cul::Provider::Features& f) const override
+    {
+        if (impl) return impl->supports(f);
+        return false;
+    }
+
+    bool requires(const cul::Provider::Requirements& r) const override
+    {
+        if (impl) return impl->requires(r);
+        return true;
+    }
+
+    void on_wifi_and_cell_reporting_state_changed(cul::WifiAndCellIdReportingState state) override
+    {
+        if (impl) impl->on_wifi_and_cell_reporting_state_changed(state);
+    }
+
+    void on_reference_location_updated(const cul::Update<cul::Position>& position) override
+    {
+        if (impl) impl->on_reference_location_updated(position);
+    }
+
+    void on_reference_velocity_updated(const cul::Update<cul::Velocity>& velocity) override
+    {
+        if (impl) impl->on_reference_velocity_updated(velocity);
+    }
+
+    void on_reference_heading_updated(const cul::Update<cul::Heading>& heading) override
+    {
+        if (impl) impl->on_reference_heading_updated(heading);
+    }
+
+    void start_position_updates() override
+    {
+        if (impl) impl->state_controller()->start_position_updates();
+    }
+
+    void stop_position_updates() override
+    {
+        if (impl) impl->state_controller()->stop_position_updates();
+    }
+
+    void start_heading_updates() override
+    {
+        if (impl) impl->state_controller()->start_heading_updates();
+    }
+
+    void stop_heading_updates() override
+    {
+        if (impl) impl->state_controller()->stop_heading_updates();
+    }
+
+    void start_velocity_updates() override
+    {
+        if (impl) impl->state_controller()->start_velocity_updates();
+    }
+
+    void stop_velocity_updates() override
+    {
+        if (impl) impl->state_controller()->stop_velocity_updates();
+    }
+
+private:
+    core::dbus::DBus dbus;
+    std::unique_ptr<core::dbus::ServiceWatcher> service_watcher;
+    core::ScopedConnection service_registered;
+    cul::Provider::Ptr impl;
+};
+
 struct Runtime
 {
     static Runtime& instance()
@@ -190,7 +287,19 @@
     auto service = dbus::Service::use_service(bus, name);
     auto object = service->object_for_path(path);
 
-    return create_instance_with_config(remote::stub::Configuration{object});
+    try
+    {
+        auto result = create_instance_with_config(remote::stub::Configuration{object});
+    } catch (const std::runtime_error& e)
+    {
+        std::cerr << "Error creating remote provider, creating facade for watching the service and delayed initialization" << std::endl;
+    }
+
+    return std::make_shared<NotYet>(bus, name, [bus, name, path]()
+    {
+         auto object = dbus::Service::use_service(bus, name)->object_for_path(path);
+         return create_instance_with_config(remote::stub::Configuration{object});
+    });
 }
 
 cul::Provider::Ptr remote::Provider::Stub::create_instance_with_config(const remote::stub::Configuration& config)

=== modified file 'src/location_service/com/ubuntu/location/providers/remote/provider.h'
--- src/location_service/com/ubuntu/location/providers/remote/provider.h	2015-01-26 19:11:46 +0000
+++ src/location_service/com/ubuntu/location/providers/remote/provider.h	2015-01-27 14:28:08 +0000
@@ -40,7 +40,8 @@
 {
     class Stub : public com::ubuntu::location::Provider, public std::enable_shared_from_this<Stub>
     {
-    public:
+    public:        
+
         // For integration with the Provider factory.
         static std::string class_name();