view: Add view_update_generator -> sharded<storage_proxy> dependency

The generator will be responsible for spreading view updates with the
help of mutate_MV helper. The latter needs storage proxy to operate, so
the generator gets this dependency in advance.

There's no need to change start/stop order at the moment, generator
already starts after and stops before proxy. Also, services that have
generator as dependency are not required by proxy (even indirectly) so
no circular dependency is produced at this point.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

db/view/view_update_generator.cc

@@ -90,9 +90,13 @@ public:
     }
 };
 
-view_update_generator::view_update_generator(replica::database& db) : _db(db), _progress_tracker(std::make_unique<progress_tracker>()) {
+view_update_generator::view_update_generator(replica::database& db, sharded<service::storage_proxy>& proxy)
+        : _db(db)
+        , _proxy(proxy)
+        , _progress_tracker(std::make_unique<progress_tracker>()) {
     setup_metrics();
     discover_staging_sstables();
+    (void)_proxy;
 }
 
 view_update_generator::~view_update_generator() {}

db/view/view_update_generator.hh

@@ -22,6 +22,10 @@ class database;
 class table;
 }
 
+namespace service {
+class storage_proxy;
+}
+
 namespace db::view {
 
 class view_update_generator {
@@ -30,6 +34,7 @@ public:
 
 private:
     replica::database& _db;
+    sharded<service::storage_proxy>& _proxy;
     seastar::abort_source _as;
     future<> _started = make_ready_future<>();
     seastar::condition_variable _pending_sstables;
@@ -40,7 +45,7 @@ private:
     class progress_tracker;
     std::unique_ptr<progress_tracker> _progress_tracker;
 public:
-    view_update_generator(replica::database& db);
+    view_update_generator(replica::database& db, sharded<service::storage_proxy>& proxy);
     ~view_update_generator();
 
     future<> start();

main.cc

@@ -1269,7 +1269,7 @@ To start the scylla server proper, simply invoke as: scylla server (or just scyl
             replica::distributed_loader::init_non_system_keyspaces(db, proxy, sys_ks).get();
 
             supervisor::notify("starting view update generator");
-            view_update_generator.start(std::ref(db)).get();
+            view_update_generator.start(std::ref(db), std::ref(proxy)).get();
 
             supervisor::notify("starting commit log");
             auto cl = db.local().commitlog();

test/lib/cql_test_env.cc

@@ -839,7 +839,7 @@ public:
                 raft_gr.invoke_on_all(&service::raft_group_registry::drain_on_shutdown).get();
             });
 
-            view_update_generator.start(std::ref(db)).get();
+            view_update_generator.start(std::ref(db), std::ref(proxy)).get();
             view_update_generator.invoke_on_all(&db::view::view_update_generator::start).get();
             auto stop_view_update_generator = defer([&view_update_generator] {
                 view_update_generator.stop().get();