[1976] Call the reload command from auth server

Tests are not yet enabled. This is slightly against the TDD approach,
but the tests are mostly written, they just need to be enabled and
refactored, so it's not that bad.

src/bin/auth/command.cc

@@ -17,8 +17,7 @@
 #include <auth/auth_srv.h>
 
 #include <cc/data.h>
-#include <datasrc/memory_datasrc.h>
-#include <datasrc/factory.h>
+#include <datasrc/client_list.h>
 #include <config/ccsession.h>
 #include <exceptions/exceptions.h>
 #include <dns/rrclass.h>
@@ -146,159 +145,68 @@ class LoadZoneCommand : public AuthCommand {
 public:
     virtual void exec(AuthSrv& server, isc::data::ConstElementPtr args) {
         // parse and validate the args.
-        if (!validate(server, args)) {
+        if (!validate(args)) {
             return;
         }
 
-        const ConstElementPtr zone_config = getZoneConfig(server);
+        const boost::shared_ptr<isc::datasrc::ConfigurableClientList>
+            list(server.getClientList(zone_class_));
 
-        // Load a new zone and replace the current zone with the new one.
-        // TODO: eventually this should be incremental or done in some way
-        // that doesn't block other server operations.
-        // TODO: we may (should?) want to check the "last load time" and
-        // the timestamp of the file and skip loading if the file isn't newer.
-        const ConstElementPtr type(zone_config->get("filetype"));
-        boost::shared_ptr<InMemoryZoneFinder> zone_finder(
-            new InMemoryZoneFinder(old_zone_finder_->getClass(),
-                                   old_zone_finder_->getOrigin()));
-        if (type && type->stringValue() == "sqlite3") {
-            scoped_ptr<DataSourceClientContainer>
-                container(new DataSourceClientContainer("sqlite3",
-                                                        Element::fromJSON(
-                    "{\"database_file\": \"" +
-                    zone_config->get("file")->stringValue() + "\"}")));
-            zone_finder->load(*container->getInstance().getIterator(
-                old_zone_finder_->getOrigin()));
-        } else {
-            zone_finder->load(old_zone_finder_->getFileName());
+        if (!list) {
+            isc_throw(AuthCommandError, "There's no client list for "
+                      "class " << zone_class_);
+        }
+
+        switch (list->reload(origin_)) {
+            case ConfigurableClientList::ZONE_RELOADED:
+                // Everything worked fine.
+                LOG_DEBUG(auth_logger, DBG_AUTH_OPS, AUTH_LOAD_ZONE)
+                    .arg(zone_class_).arg(origin_);
+                return;
+            case ConfigurableClientList::ZONE_NOT_FOUND:
+                isc_throw(AuthCommandError, "Zone " << origin_ << "/" <<
+                          zone_class_ << " was not found in any configure "
+                          "data source. Configure it first.");
+            case ConfigurableClientList::ZONE_NOT_CACHED:
+                isc_throw(AuthCommandError, "Zone " << origin_ << "/" <<
+                          zone_class_ << " is not served from memory, but "
+                          "direcly from the data source. It is not possible "
+                          "to reload into memory, configure it to be cached "
+                          "first.");
+            case ConfigurableClientList::CACHE_DISABLED:
+                // This is an internal error. Auth server must have the cache
+                // enabled.
+                isc_throw(isc::Unexpected, "Cache disabled in client list of "
+                          "class " << zone_class_);
         }
-        old_zone_finder_->swap(*zone_finder);
-        LOG_DEBUG(auth_logger, DBG_AUTH_OPS, AUTH_LOAD_ZONE)
-                  .arg(zone_finder->getOrigin()).arg(zone_finder->getClass());
     }
 
 private:
-    // zone finder to be updated with the new file.
-    boost::shared_ptr<InMemoryZoneFinder> old_zone_finder_;
+    // Parsed arguments
+    RRClass zone_class_;
+    Name origin_;
 
     // A helper private method to parse and validate command parameters.
     // On success, it sets 'old_zone_finder_' to the zone to be updated.
     // It returns true if everything is okay; and false if the command is
     // valid but there's no need for further process.
-    bool validate(AuthSrv& , isc::data::ConstElementPtr ) {
-#if 0
-        TODO: Rewrite
+    bool validate(isc::data::ConstElementPtr args) {
         if (args == NULL) {
             isc_throw(AuthCommandError, "Null argument");
         }
 
-        // In this initial implementation, we assume memory data source
-        // for class IN by default.
-        ConstElementPtr datasrc_elem = args->get("datasrc");
-        if (datasrc_elem) {
-            if (datasrc_elem->stringValue() == "sqlite3") {
-                LOG_DEBUG(auth_logger, DBG_AUTH_OPS, AUTH_SQLITE3);
-                return (false);
-            } else if (datasrc_elem->stringValue() != "memory") {
-                // (note: at this point it's guaranteed that datasrc_elem
-                // is of string type)
-                isc_throw(AuthCommandError,
-                          "Data source type " << datasrc_elem->stringValue()
-                          << " is not supported");
-            }
-        }
-
         ConstElementPtr class_elem = args->get("class");
-        const RRClass zone_class =
-            class_elem ? RRClass(class_elem->stringValue()) : RRClass::IN();
-
-        isc::datasrc::DataSourceClient* datasrc(
-            server.getInMemoryClient(zone_class));
-        if (datasrc == NULL) {
-            isc_throw(AuthCommandError, "Memory data source is disabled");
-        }
+        zone_class_ = class_elem ? RRClass(class_elem->stringValue()) :
+            RRClass::IN();
 
         ConstElementPtr origin_elem = args->get("origin");
         if (!origin_elem) {
             isc_throw(AuthCommandError, "Zone origin is missing");
         }
-        const Name origin = Name(origin_elem->stringValue());
-
-        // Get the current zone
-        const DataSourceClient::FindResult result = datasrc->findZone(origin);
-        if (result.code != result::SUCCESS) {
-            isc_throw(AuthCommandError, "Zone " << origin <<
-                      " is not found in data source");
-        }
-
-        // It would appear that dynamic_cast does not work on all systems;
-        // it seems to confuse the RTTI system, resulting in NULL return
-        // values. So we use the more dangerous static_pointer_cast here.
-        old_zone_finder_ = boost::static_pointer_cast<InMemoryZoneFinder>(
-            result.zone_finder);
+        origin_ = Name(origin_elem->stringValue());
 
-#endif
         return (true);
     }
-
-    ConstElementPtr getZoneConfig(const AuthSrv &server) {
-        if (!server.getConfigSession()) {
-            // FIXME: This is a hack to make older tests pass. We should
-            // update these tests as well sometime and remove this hack.
-            // (note that under normal situation, the
-            // server.getConfigSession() does not return NULL)
-
-            // We provide an empty map, which means no configuration --
-            // defaults.
-            return (ConstElementPtr(new MapElement()));
-        }
-
-        // Find the config corresponding to the zone.
-        // We expect the configuration to be valid, as we have it and we
-        // accepted it before, therefore it must be validated.
-        const ConstElementPtr config(server.getConfigSession()->
-                                     getValue("datasources"));
-        ConstElementPtr zone_list;
-        // Unfortunately, we need to walk the list to find the correct data
-        // source.
-        // TODO: Make it named sets. These lists are uncomfortable.
-        for (size_t i(0); i < config->size(); ++i) {
-            // We use the getValue to get defaults as well
-            const ConstElementPtr dsrc_config(config->get(i));
-            const ConstElementPtr class_config(dsrc_config->get("class"));
-            const string class_type(class_config ?
-                                    class_config->stringValue() : "IN");
-            // It is in-memory and our class matches.
-            // FIXME: Is it allowed to have two datasources for the same
-            // type and class at once? It probably would not work now
-            // anyway and we may want to change the configuration of
-            // datasources somehow.
-            if (dsrc_config->get("type")->stringValue() == "memory" &&
-                RRClass(class_type) == old_zone_finder_->getClass()) {
-                zone_list = dsrc_config->get("zones");
-                break;
-            }
-        }
-
-        if (!zone_list) {
-            isc_throw(AuthCommandError,
-                      "Corresponding data source configuration was not found");
-        }
-
-        // Now we need to walk the zones and find the correct one.
-        for (size_t i(0); i < zone_list->size(); ++i) {
-            const ConstElementPtr zone_config(zone_list->get(i));
-            if (Name(zone_config->get("origin")->stringValue()) ==
-                old_zone_finder_->getOrigin()) {
-                // The origins are the same, so we consider this config to be
-                // for the zone.
-                return (zone_config);
-            }
-        }
-
-        isc_throw(AuthCommandError,
-                  "Corresponding zone configuration was not found");
-    }
 };
 
 // The factory of command objects.