C++ Glacier2/session demo

cpp/Glacier2/session/.gitignore

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+# Default cmake build directory
+build

cpp/Glacier2/session/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.21)
+
+project(glacier2_session CXX)
+
+include(../../cmake/common.cmake)
+
+add_executable(client PokeBox.ice Client.cpp)
+
+slice2cpp_generate(client)
+target_link_libraries(client PRIVATE Ice::Ice Ice::Glacier2)
+if(WIN32)
+  add_custom_command(TARGET client POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy -t $<TARGET_FILE_DIR:client>
+      $<TARGET_RUNTIME_DLLS:client>
+      $<GENEX_EVAL:$<TARGET_PROPERTY:Ice::Ice,ICE_RUNTIME_DLLS>>
+    COMMAND_EXPAND_LISTS
+  )
+endif()
+
+add_executable(
+  server
+  DefaultPokeSession.cpp
+  DefaultPokeSession.h
+  InMemoryPokeStore.cpp
+  InMemoryPokeStore.h
+  PokeBox.ice
+  PokeStore.h
+  Server.cpp
+  SessionManager.cpp
+  SessionManager.h
+  SharedPokeBox.cpp
+  SharedPokeBox.h
+  UserIdResolver.h)
+
+slice2cpp_generate(server)
+target_link_libraries(server PRIVATE Ice::Ice Ice::Glacier2)
+if(WIN32)
+  add_custom_command(TARGET server POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy -t $<TARGET_FILE_DIR:server>
+      $<TARGET_RUNTIME_DLLS:server>
+      $<GENEX_EVAL:$<TARGET_PROPERTY:Ice::Ice,ICE_RUNTIME_DLLS>>
+    COMMAND_EXPAND_LISTS
+  )
+endif()

cpp/Glacier2/session/Client.cpp

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+// Copyright (c) ZeroC, Inc.
+
+#include "../../common/Env.h"
+#include "PokeBox.h"
+
+#include <Glacier2/Glacier2.h>
+#include <Ice/Ice.h>
+#include <array>
+#include <cassert>
+#include <iostream>
+#include <random>
+
+using namespace std;
+using namespace CatchThemAll;
+
+// All the Pokemon we know about.
+std::array<const char*, 57> allPokemon = {
+    "Bulbasaur", "Ivysaur",  "Venusaur",  "Charmander", "Charmeleon", "Charizard", "Squirtle",   "Wartortle",
+    "Blastoise", "Caterpie", "Metapod",   "Butterfree", "Weedle",     "Kakuna",    "Beedrill",   "Pidgey",
+    "Pidgeotto", "Pidgeot",  "Rattata",   "Raticate",   "Spearow",    "Fearow",    "Ekans",      "Arbok",
+    "Pikachu",   "Raichu",   "Sandshrew", "Sandslash",  "Nidoran♀",   "Nidorina",  "Nidoqueen",  "Nidoran♂",
+    "Nidorino",  "Nidoking", "Clefairy",  "Clefable",   "Vulpix",     "Ninetales", "Jigglypuff", "Wigglytuff",
+    "Zubat",     "Golbat",   "Oddish",    "Gloom",      "Vileplume",  "Paras",     "Parasect",   "Venonat",
+    "Venomoth",  "Diglett",  "Dugtrio",   "Meowth",     "Persian",    "Psyduck",   "Golduck",    "Mankey",
+    "Primeape"};
+
+int
+main(int argc, char* argv[])
+{
+    // Retrieve the user ID for this run.
+    string userId = argc > 1 ? argv[1] : Env::getUsername();
+
+    // Create an Ice communicator. We'll use this communicator to create proxies and manage outgoing connections.
+    Ice::CommunicatorPtr communicator = Ice::initialize(argc, argv);
+
+    // Make sure the communicator is destroyed at the end of this scope.
+    Ice::CommunicatorHolder communicatorHolder{communicator};
+
+    // Create a proxy to the Glacier2 router. The addressing information (transport, host, and port number) is derived
+    // from the value of Glacier2.Client.Endpoints in the glacier2 router configuration file.
+    Glacier2::RouterPrx router{communicator, "Glacier2/router:tcp -h localhost -p 4063"};
+
+    // Set this proxy as the default router for all future proxies created from this communicator.
+    communicator->setDefaultRouter(router);
+
+    // Create a session with the Glacier2 router. In this demo, the Glacier2 router is configured to accept any
+    // username/password combination. This call establishes a network connection to the Glacier2 router; the lifetime
+    // of the session is the same as the lifetime of the connection.
+    optional<Glacier2::SessionPrx> session = router->createSession(userId, "password");
+
+    // We configured a SessionManager on the Glacier2 router, so session is a non-null PokeSession.
+    assert(session);
+    auto pokeSession = Ice::uncheckedCast<PokeSessionPrx>(*session);
+
+    // Retrieve the PokeBox proxy from the session.
+    optional<PokeBoxPrx> pokeBox = pokeSession->getPokeBox();
+    assert(pokeBox);
+
+    size_t currentCount = pokeBox->getInventory().size();
+    cout << userId << "'s PokeBox contains " << currentCount << " Pokémon." << endl;
+
+    // Catch a few Pokémon.
+    // Initialize random number generators.
+    std::mt19937 gen{std::random_device{}()};
+    std::uniform_int_distribution<size_t> addDist{1, 6};
+    std::uniform_int_distribution<size_t> pokeDist{0, allPokemon.size() - 1};
+    size_t addCount = addDist(gen);
+    cout << "Catching " << addCount << " Pokémon... " << endl;
+    vector<string> newPokemon;
+    newPokemon.reserve(addCount);
+    for (size_t i = 0; i < addCount; ++i)
+    {
+        newPokemon.emplace_back(allPokemon[pokeDist(gen)]);
+    }
+    pokeBox->caught(newPokemon);
+
+    // Display the contents of the PokeBox.
+    PokemonList inventory = pokeBox->getInventory();
+    cout << userId << "'s PokeBox now holds " << inventory.size() << " Pokémon:" << endl;
+    for (const string& pokemon : inventory)
+    {
+        cout << "\t" << pokemon << endl;
+    }
+
+    if (inventory.size() > 10)
+    {
+        cout << "Oh no! All the Pokémon escaped!" << endl;
+        pokeBox->releaseAll();
+    }
+
+    // Exiting, closing the connection, or calling `destroy(Async)` on the session terminates both PokeSession and the
+    // internal session state maintained by the Glacier2 router.
+    cout << "Destroying the session..." << endl;
+    pokeSession->destroy();
+
+    // Verify the proxy no longer works.
+    try
+    {
+        pokeBox->getInventory();
+        cout << "Error: the PokeBox proxy should not work without a session!" << endl;
+    }
+    catch (const Ice::ConnectionLostException&)
+    {
+        // We get a ConnectionLostException because the Glacier2 router aborts the request on the (new) connection
+        // without an associated session.
+        cout << "The PokeBox proxy is no longer valid, as expected." << endl;
+    }
+
+    // Create a new session. This allows us to reach the PokeBox object again.
+    cout << "Creating a new session..." << endl;
+    session = router->createSession(userId, "password");
+
+    try
+    {
+        // The pokeBox proxy no longer works as it was created with the token of an old session.
+        pokeBox->getInventory();
+        cout << "Error: the PokeBox proxy should not work with a new session!" << endl;
+    }
+    catch (const Ice::DispatchException& dispatchException)
+    {
+        if (dispatchException.replyStatus() == Ice::ReplyStatus::Unauthorized)
+        {
+            // See code in SharedPokeBox::getUserId.
+            cout << "The PokeBox proxy remains unusable, as expected." << endl;
+        }
+        else
+        {
+            throw;
+        }
+    }
+
+    return 0;
+}

cpp/Glacier2/session/DefaultPokeSession.cpp

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+// Copyright (c) ZeroC, Inc.
+
+#include "DefaultPokeSession.h"
+
+#include <iostream>
+
+using namespace Server;
+using namespace std;
+
+DefaultPokeSession::DefaultPokeSession(
+    Ice::ObjectAdapterPtr adapter,
+    Glacier2::SessionControlPrx sessionControl,
+    UserIdResolverPtr userIdResolver)
+    : _adapter(std::move(adapter)),
+      _sessionControl(std::move(sessionControl)),
+      _userIdResolver(std::move(userIdResolver))
+{
+}
+
+void
+DefaultPokeSession::destroy(const Ice::Current& current)
+{
+    cout << "Destroying session #" << current.id.name << endl;
+
+    // Remove the token from the user ID resolver, since the token is no longer valid.
+    _userIdResolver->removeToken(current.id.name);
+
+    // Remove this servant from the object adapter. A new call to this session object will fail with
+    // ObjectNotExistException.
+    _adapter->remove(current.id);
+
+    // Destroy the session in the Glacier2 router.
+    _sessionControl->destroy();
+}
+
+optional<CatchThemAll::PokeBoxPrx>
+DefaultPokeSession::getPokeBox(const Ice::Current& current)
+{
+    // The session token is the name component of the session identity; we use it for the identity of the PokeBox
+    // object as well.
+    return _adapter->createProxy<CatchThemAll::PokeBoxPrx>(Ice::Identity{current.id.name, "PokeBox"});
+}

cpp/Glacier2/session/DefaultPokeSession.h

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+// Copyright (c) ZeroC, Inc.
+
+#ifndef DEFAULT_POKE_SESSION_H
+#define DEFAULT_POKE_SESSION_H
+
+#include "PokeBox.h"
+#include "UserIdResolver.h"
+
+namespace Server
+{
+    /// DefaultPokeSession is an Ice servant that implements Slice interface PokeSession. We create a
+    /// DefaultPokeSession for each PokeSession object.
+    class DefaultPokeSession : public CatchThemAll::PokeSession
+    {
+    public:
+        /// Constructs a DefaultPokeSession servant.
+        /// @param adapter The object adapter that hosts this servant and the PokeBox objects.
+        /// @param sessionControl The session control proxy.
+        /// @param userIdResolver The user ID resolver.
+        DefaultPokeSession(
+            Ice::ObjectAdapterPtr adapter,
+            Glacier2::SessionControlPrx sessionControl,
+            UserIdResolverPtr userIdResolver);
+
+        void destroy(const Ice::Current& current) final;
+
+        // Implements the pure virtual function in the base class (CatchThemAll::PokeSession) generated by the Slice
+        // compiler.
+        std::optional<CatchThemAll::PokeBoxPrx> getPokeBox(const Ice::Current&) final;
+
+    private:
+        // The object adapter that hosts this servant and the PokeBox objects.
+        Ice::ObjectAdapterPtr _adapter;
+
+        // A proxy to the SessionControl object hosted by the Glacier2 router; this proxy allows us to control the
+        // Glacier2 session, in particular to destroy it. In this demo, that's the only per-session state maintained by
+        // DefaultPokeSession.
+        Glacier2::SessionControlPrx _sessionControl;
+
+        UserIdResolverPtr _userIdResolver;
+    };
+}
+
+#endif

cpp/Glacier2/session/InMemoryPokeStore.cpp

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+
+#include "InMemoryPokeStore.h"
+
+using namespace Server;
+using namespace std;
+
+void
+InMemoryPokeStore::saveCollection(const string& userId, CatchThemAll::PokemonList pokemon)
+{
+    if (pokemon.empty())
+    {
+        _store.erase(userId);
+    }
+    else
+    {
+        _store[userId] = std::move(pokemon);
+    }
+}
+
+CatchThemAll::PokemonList
+InMemoryPokeStore::retrieveCollection(const string& userId) const
+{
+    auto it = _store.find(userId);
+    return it == _store.end() ? CatchThemAll::PokemonList{} : it->second;
+}

cpp/Glacier2/session/InMemoryPokeStore.h

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+// Copyright (c) ZeroC, Inc.
+
+#ifndef IN_MEMORY_POKE_STORE_H
+#define IN_MEMORY_POKE_STORE_H
+
+#include "PokeStore.h"
+#include <map>
+#include <string>
+
+namespace Server
+{
+    /// An in-memory implementation of PokeStore.
+    /// @remark This mock implementation is not thread-safe. A real implementation should support concurrent calls.
+    class InMemoryPokeStore : public PokeStore
+    {
+    public:
+        void saveCollection(const std::string& userId, CatchThemAll::PokemonList pokemon) final;
+        [[nodiscard]] CatchThemAll::PokemonList retrieveCollection(const std::string& userId) const final;
+
+    private:
+        std::map<std::string, CatchThemAll::PokemonList> _store;
+    };
+}
+
+#endif

cpp/Glacier2/session/PokeBox.ice

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+// Copyright (c) ZeroC, Inc.
+
+// Include the Glacier2/Session.ice file included in the Glacier2 NuGet package.
+#include <Glacier2/Session.ice>
+
+module CatchThemAll
+{
+    /// Represents a list of Pokémon.
+    sequence<string> PokemonList;
+
+    /// Represents the Pokémon collected by a user.
+    interface PokeBox
+    {
+        /// Lists all the Pokémon in this box.
+        /// @return The list of Pokémon.
+        PokemonList getInventory();
+
+        /// Adds one or more Pokémon to this box.
+        /// @param pokemon The Pokémon to add.
+        void caught(PokemonList pokemon);
+
+        /// Releases all the Pokémon.
+        void releaseAll();
+    }
+
+    /// Represents a specialized session for our Pokémon application.
+    interface PokeSession : Glacier2::Session
+    {
+        /// Retrieves the PokeBox proxy associated with this session.
+        /// @return The PokeBox proxy.
+        PokeBox* getPokeBox();
+    }
+}

cpp/Glacier2/session/PokeStore.h

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+// Copyright (c) ZeroC, Inc.
+
+#ifndef POKE_STORE_H
+#define POKE_STORE_H
+
+#include "PokeBox.h"
+
+namespace Server
+{
+    /// Represents a Pokémon storage system.
+    class PokeStore
+    {
+    public:
+        virtual ~PokeStore() = default;
+
+        /// Saves the Pokémon collection for a specific user.
+        /// @param userId The user ID.
+        /// @param pokemon The Pokémon collection to save.
+        virtual void saveCollection(const std::string& userId, CatchThemAll::PokemonList pokemon) = 0;
+
+        /// Retrieves the Pokémon collection for a specific user.
+        /// @param userId The user ID.
+        /// @returns The saved Pokémon collection, or an empty list if no collection was saved for @p userId.
+        [[nodiscard]] virtual CatchThemAll::PokemonList retrieveCollection(const std::string& userId) const = 0;
+    };
+
+    using PokeStorePtr = std::shared_ptr<PokeStore>;
+}
+
+#endif