[#3536] implemented register and deregister in lease mgr factory

Author: Razvan Becheriu

src/bin/dhcp4/json_config_parser.cc

@@ -25,6 +25,7 @@
 #include <dhcpsrv/cfgmgr.h>
 #include <dhcpsrv/config_backend_dhcp4_mgr.h>
 #include <dhcpsrv/db_type.h>
+#include <dhcpsrv/lease_mgr_factory.h>
 #include <dhcpsrv/parsers/client_class_def_parser.h>
 #include <dhcpsrv/parsers/dhcp_parsers.h>
 #include <dhcpsrv/parsers/expiration_config_parser.h>
@@ -341,9 +342,6 @@ processDhcp4Config(isc::data::ConstElementPtr config_set) {
     // for option definitions. This is equivalent to committing empty container.
     LibDHCP::setRuntimeOptionDefs(OptionDefSpaceContainer());
 
-    // Print the list of known backends.
-    HostDataSourceFactory::printRegistered();
-
     // Answer will hold the result.
     ConstElementPtr answer;
 
@@ -902,8 +900,15 @@ configureDhcp4Server(Dhcpv4Srv& server, isc::data::ConstElementPtr config_set,
         }
     }
 
+    // Print the list of known backends.
+    LeaseMgrFactory::printRegistered();
+
+    // Print the list of known backends.
+    HostDataSourceFactory::printRegistered();
+
     // Moved from the commit block to add the config backend indication.
     if (status_code == CONTROL_RESULT_SUCCESS && (!check_only || extra_checks)) {
+
         try {
             // If there are config backends, fetch and merge into staging config
             server.getCBControl()->databaseConfigFetch(srv_config,

src/bin/dhcp4/tests/dhcp4_test_utils.cc

@@ -828,7 +828,7 @@ Dhcpv4SrvTest::configure(const std::string& config,
     ConstElementPtr json;
     try {
         json = parseJSON(config);
-    } catch (const std::exception& ex){
+    } catch (const std::exception& ex) {
         // Fatal failure on parsing error
         FAIL() << "parsing failure:"
                << "config:" << config << std::endl

src/bin/dhcp6/json_config_parser.cc

@@ -24,6 +24,7 @@
 #include <dhcpsrv/cfg_option.h>
 #include <dhcpsrv/cfgmgr.h>
 #include <dhcpsrv/db_type.h>
+#include <dhcpsrv/lease_mgr_factory.h>
 #include <dhcpsrv/parsers/client_class_def_parser.h>
 #include <dhcpsrv/parsers/dhcp_parsers.h>
 #include <dhcpsrv/parsers/duid_config_parser.h>
@@ -443,9 +444,6 @@ processDhcp6Config(isc::data::ConstElementPtr config_set) {
     // for option definitions. This is equivalent to committing empty container.
     LibDHCP::setRuntimeOptionDefs(OptionDefSpaceContainer());
 
-    // Print the list of known backends.
-    HostDataSourceFactory::printRegistered();
-
     // Answer will hold the result.
     ConstElementPtr answer;
 
@@ -1038,6 +1036,12 @@ configureDhcp6Server(Dhcpv6Srv& server, isc::data::ConstElementPtr config_set,
         }
     }
 
+    // Print the list of known backends.
+    LeaseMgrFactory::printRegistered();
+
+    // Print the list of known backends.
+    HostDataSourceFactory::printRegistered();
+
     // Moved from the commit block to add the config backend indication.
     if (status_code == CONTROL_RESULT_SUCCESS && (!check_only || extra_checks)) {
         try {

src/bin/dhcp6/tests/dhcp6_test_utils.cc

@@ -51,7 +51,7 @@ BaseServerTest::~BaseServerTest() {
     // Revert to original data directory.
     CfgMgr::instance().setDataDir(original_datadir_);
 
-    // Revert to unit test logging in case the test reconfigured logging.
+    // Revert to unit test logging, in case the test reconfigured it.
     isc::log::initLogger();
 }
 
@@ -606,7 +606,6 @@ Dhcpv6SrvTest::testReleaseBasic(Lease::Type type, const IOAddress& existing,
 
     ObservationPtr stat = StatsMgr::instance().getObservation(name);
     ASSERT_TRUE(stat);
-    uint64_t before = stat->getInteger().first;
 
     // Let's create a RELEASE
     Pkt6Ptr rel = createMessage(DHCPV6_RELEASE, type, release_addr, prefix_len,

src/hooks/dhcp/lease_cmds/tests/lease_cmds4_unittest.cc

@@ -3519,12 +3519,12 @@ TEST_F(Lease4CmdsTest, lease4AddDeclinedLeasesMultiThreading) {
 }
 
 TEST_F(Lease4CmdsTest, lease4AddReleasedLeases) {
-    testLease4AddDeclinedLeases();
+    testLease4AddReleasedLeases();
 }
 
 TEST_F(Lease4CmdsTest, lease4AddReleasedLeasesMultiThreading) {
     MultiThreadingTest mt(true);
-    testLease4AddDeclinedLeases();
+    testLease4AddReleasedLeases();
 }
 
 TEST_F(Lease4CmdsTest, lease4AddExisting) {

src/lib/dhcpsrv/dhcpsrv_messages.cc

@@ -69,6 +69,9 @@ extern const isc::log::MessageID DHCPSRV_LEASE4_EXTENDED_INFO_SANITY_FAIL = "DHC
 extern const isc::log::MessageID DHCPSRV_LEASE4_EXTENDED_INFO_UPGRADED = "DHCPSRV_LEASE4_EXTENDED_INFO_UPGRADED";
 extern const isc::log::MessageID DHCPSRV_LEASE6_EXTENDED_INFO_SANITY_FAIL = "DHCPSRV_LEASE6_EXTENDED_INFO_SANITY_FAIL";
 extern const isc::log::MessageID DHCPSRV_LEASE6_EXTENDED_INFO_UPGRADED = "DHCPSRV_LEASE6_EXTENDED_INFO_UPGRADED";
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED = "DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED";
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER = "DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER";
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKEND_REGISTER = "DHCPSRV_LEASE_MGR_BACKEND_REGISTER";
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_CALLBACK_EXCEPTION = "DHCPSRV_LEASE_MGR_CALLBACK_EXCEPTION";
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_CALLBACK_UNKNOWN_EXCEPTION = "DHCPSRV_LEASE_MGR_CALLBACK_UNKNOWN_EXCEPTION";
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_DB_OPEN_CONNECTION_WITH_RETRY_FAILED = "DHCPSRV_LEASE_MGR_DB_OPEN_CONNECTION_WITH_RETRY_FAILED";
@@ -339,6 +342,9 @@ const char* values[] = {
     "DHCPSRV_LEASE4_EXTENDED_INFO_UPGRADED", "extended info for lease %1 was upgraded",
     "DHCPSRV_LEASE6_EXTENDED_INFO_SANITY_FAIL", "extended info for lease %1 failed checks (%2)",
     "DHCPSRV_LEASE6_EXTENDED_INFO_UPGRADED", "extended info for lease %1 was upgraded",
+    "DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED", "the following lease backend types are available: %1",
+    "DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER", "deregistered lease backend type: %1",
+    "DHCPSRV_LEASE_MGR_BACKEND_REGISTER", "registered lease backend type: %1",
     "DHCPSRV_LEASE_MGR_CALLBACK_EXCEPTION", "exception occurred in a lease manager callback for callback type %1, subnet id %2, and lease %3: %4",
     "DHCPSRV_LEASE_MGR_CALLBACK_UNKNOWN_EXCEPTION", "unknown exception occurred in a lease manager callback for callback type %1, subnet id %2, and lease %3",
     "DHCPSRV_LEASE_MGR_DB_OPEN_CONNECTION_WITH_RETRY_FAILED", "Failed to connect to database: %1 with error: %2",

src/lib/dhcpsrv/dhcpsrv_messages.h

@@ -70,6 +70,9 @@ extern const isc::log::MessageID DHCPSRV_LEASE4_EXTENDED_INFO_SANITY_FAIL;
 extern const isc::log::MessageID DHCPSRV_LEASE4_EXTENDED_INFO_UPGRADED;
 extern const isc::log::MessageID DHCPSRV_LEASE6_EXTENDED_INFO_SANITY_FAIL;
 extern const isc::log::MessageID DHCPSRV_LEASE6_EXTENDED_INFO_UPGRADED;
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED;
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER;
+extern const isc::log::MessageID DHCPSRV_LEASE_MGR_BACKEND_REGISTER;
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_CALLBACK_EXCEPTION;
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_CALLBACK_UNKNOWN_EXCEPTION;
 extern const isc::log::MessageID DHCPSRV_LEASE_MGR_DB_OPEN_CONNECTION_WITH_RETRY_FAILED;

src/lib/dhcpsrv/dhcpsrv_messages.mes

@@ -410,6 +410,20 @@ the lease database. The operation started a retry to connect procedure.
 The database access string with password redacted is logged, along with the
 error and details for the reconnect procedure.
 
+% DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED the following lease backend types are available: %1
+This informational message lists all possible lease backends that could
+be used in lease-database.
+
+% DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER deregistered lease backend type: %1
+Logged at debug log level 40.
+This debug message is issued when a backend factory was deregistered.
+It is no longer possible to use lease backend of this type.
+
+% DHCPSRV_LEASE_MGR_BACKEND_REGISTER registered lease backend type: %1
+Logged at debug log level 40.
+This debug message is issued when a backend factory was successfully
+registered. It is now possible to use lease backend of this type.
+
 % DHCPSRV_LEASE_SANITY_FAIL The lease %1 with subnet-id %2 failed subnet-id checks (%3).
 This warning message is printed when the lease being loaded does not match the
 configuration. Due to lease-checks value, the lease will be loaded, but

src/lib/dhcpsrv/host_data_source_factory.cc

@@ -184,6 +184,7 @@ using namespace isc::dhcp;
 
 namespace {
 
+// Code will be moved to appropriate hook library.
 #ifdef HAVE_MYSQL
 struct MySqlHostDataSourceInit {
     // Constructor registers
@@ -209,6 +210,7 @@ struct MySqlHostDataSourceInit {
 MySqlHostDataSourceInit mysql_init_;
 #endif
 
+// Code will be moved to appropriate hook library.
 #ifdef HAVE_PGSQL
 struct PgSqlHostDataSourceInit {
     // Constructor registers

src/lib/dhcpsrv/lease_mgr_factory.cc

@@ -31,9 +31,11 @@ using namespace std;
 namespace isc {
 namespace dhcp {
 
-boost::scoped_ptr<TrackingLeaseMgr>&
+map<string, LeaseMgrFactory::Factory> LeaseMgrFactory::map_;
+
+TrackingLeaseMgrPtr&
 LeaseMgrFactory::getLeaseMgrPtr() {
-    static boost::scoped_ptr<TrackingLeaseMgr> lease_mgr_ptr;
+    static TrackingLeaseMgrPtr lease_mgr_ptr;
     return (lease_mgr_ptr);
 }
 
@@ -45,47 +47,70 @@ LeaseMgrFactory::create(const std::string& dbaccess) {
     DatabaseConnection::ParameterMap parameters = DatabaseConnection::parse(dbaccess);
     std::string redacted = DatabaseConnection::redactedAccessString(parameters);
 
-    // Is "type" present?
-    if (parameters.find(type) == parameters.end()) {
+    // Get the database type and open the corresponding database
+    DatabaseConnection::ParameterMap::iterator it = parameters.find(type);
+    if (it == parameters.end()) {
         LOG_ERROR(dhcpsrv_logger, DHCPSRV_NOTYPE_DB).arg(dbaccess);
         isc_throw(InvalidParameter, "Database configuration parameters do not "
                   "contain the 'type' keyword");
     }
 
-    // Yes, check what it is.
-    if (parameters[type] == string("mysql")) {
+    // Code will be moved to appropriate hook library.
 #ifdef HAVE_MYSQL
-        LOG_INFO(dhcpsrv_logger, DHCPSRV_MYSQL_DB).arg(redacted);
-        getLeaseMgrPtr().reset(new MySqlLeaseMgr(parameters));
-        return;
-#else
-        LOG_ERROR(dhcpsrv_logger, DHCPSRV_UNKNOWN_DB).arg("mysql");
-        isc_throw(InvalidType, "The Kea server has not been compiled with "
-                  "support for database type: mysql");
+    // Factory method
+    auto mysql_factory = [](const DatabaseConnection::ParameterMap& parameters) -> TrackingLeaseMgrPtr {
+        LOG_INFO(dhcpsrv_logger, DHCPSRV_MYSQL_DB)
+            .arg(DatabaseConnection::redactedAccessString(parameters));
+        return (TrackingLeaseMgrPtr(new MySqlLeaseMgr(parameters)));
+    };
+    LeaseMgrFactory::registerFactory("mysql", mysql_factory, true);
 #endif
-    }
 
-    if (parameters[type] == string("postgresql")) {
+    // Code will be moved to appropriate hook library.
 #ifdef HAVE_PGSQL
-        LOG_INFO(dhcpsrv_logger, DHCPSRV_PGSQL_DB).arg(redacted);
-        getLeaseMgrPtr().reset(new PgSqlLeaseMgr(parameters));
-        return;
-#else
-        LOG_ERROR(dhcpsrv_logger, DHCPSRV_UNKNOWN_DB).arg("postgresql");
-        isc_throw(InvalidType, "The Kea server has not been compiled with "
-                  "support for database type: postgresql");
+    // Factory method
+    auto pgsql_factory = [](const DatabaseConnection::ParameterMap& parameters) -> TrackingLeaseMgrPtr {
+        LOG_INFO(dhcpsrv_logger, DHCPSRV_PGSQL_DB)
+            .arg(DatabaseConnection::redactedAccessString(parameters));
+        return (TrackingLeaseMgrPtr(new PgSqlLeaseMgr(parameters)));
+    };
+    LeaseMgrFactory::registerFactory("postgresql", pgsql_factory, true);
 #endif
-    }
+
     if (parameters[type] == string("memfile")) {
         LOG_INFO(dhcpsrv_logger, DHCPSRV_MEMFILE_DB).arg(redacted);
         getLeaseMgrPtr().reset(new Memfile_LeaseMgr(parameters));
         return;
     }
 
-    // Get here on no match
-    LOG_ERROR(dhcpsrv_logger, DHCPSRV_UNKNOWN_DB).arg(parameters[type]);
-    isc_throw(InvalidType, "Database access parameter 'type' does "
-              "not specify a supported database backend: " << parameters[type]);
+    string db_type = it->second;
+    auto index = map_.find(db_type);
+
+    // No match?
+    if (index == map_.end()) {
+        if ((db_type == "mysql") ||
+            (db_type == "postgresql")) {
+            LOG_ERROR(dhcpsrv_logger, DHCPSRV_UNKNOWN_DB).arg(db_type);
+            string with = (db_type == "postgresql" ? "pgsql" : db_type);
+            isc_throw(InvalidType, "The Kea server has not been compiled with "
+                      "support for database type: " << db_type
+                      << ". Did you forget to use --with-"
+                      << with << " during compilation?");
+        }
+        // Get here on no match
+        LOG_ERROR(dhcpsrv_logger, DHCPSRV_UNKNOWN_DB).arg(parameters[type]);
+        isc_throw(InvalidType, "Database access parameter 'type' does "
+                  "not specify a supported database backend: " << parameters[type]);
+    }
+
+    // Call the factory.
+    getLeaseMgrPtr() = index->second(parameters);
+
+    // Check the factory did not return NULL.
+    if (!getLeaseMgrPtr()) {
+        isc_throw(Unexpected, "Lease database " << db_type <<
+                  " factory returned NULL");
+    }
 }
 
 void
@@ -97,6 +122,14 @@ LeaseMgrFactory::destroy() {
             .arg(getLeaseMgrPtr()->getType());
     }
     getLeaseMgrPtr().reset();
+    // Code will be moved to appropriate hook library.
+#ifdef HAVE_MYSQL
+    LeaseMgrFactory::deregisterFactory("mysql", true);
+#endif
+    // Code will be moved to appropriate hook library.
+#ifdef HAVE_PGSQL
+    LeaseMgrFactory::deregisterFactory("postgresql", true);
+#endif
 }
 
 void
@@ -132,5 +165,58 @@ LeaseMgrFactory::instance() {
     return (*lmptr);
 }
 
+bool
+LeaseMgrFactory::registerFactory(const string& db_type,
+                                 const Factory& factory,
+                                 bool no_log) {
+    if (map_.count(db_type)) {
+        return (false);
+    }
+    map_.insert(pair<string, Factory>(db_type, factory));
+
+    // We are dealing here with static logger initialization fiasco.
+    // registerFactory may be called from constructors of static global
+    // objects for built in backends. The logging is not initialized yet,
+    // so the LOG_DEBUG would throw.
+    if (!no_log) {
+        LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_LEASE_MGR_BACKEND_REGISTER)
+            .arg(db_type);
+    }
+    return (true);
+}
+
+bool
+LeaseMgrFactory::deregisterFactory(const string& db_type, bool no_log) {
+    auto index = map_.find(db_type);
+    if (index != map_.end()) {
+        map_.erase(index);
+        if (!no_log) {
+            LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE,
+                    DHCPSRV_LEASE_MGR_BACKEND_DEREGISTER)
+                .arg(db_type);
+        }
+        return (true);
+    } else {
+        return (false);
+    }
+}
+
+bool
+LeaseMgrFactory::registeredFactory(const std::string& db_type) {
+    auto index = map_.find(db_type);
+    return (index != map_.end());
+}
+
+void
+LeaseMgrFactory::printRegistered() {
+    std::stringstream txt;
+
+    for (auto const& x : map_) {
+        txt << x.first << " ";
+    }
+
+    LOG_INFO(dhcpsrv_logger, DHCPSRV_LEASE_MGR_BACKENDS_REGISTERED).arg(txt.str());
+}
+
 } // namespace dhcp
 } // namespace isc