XY Allow read-only access in BACKINGUP state (for now master-only & draft)

neo/master/app.py

@@ -103,6 +103,7 @@ class Application(BaseApplication):
             self)
         self.secondary_master_handler = secondary.SecondaryMasterHandler(self)
         self.client_service_handler = client.ClientServiceHandler(self)
+        self.client_ro_service_handler = client.ClientROServiceHandler(self)
         self.storage_service_handler = storage.StorageServiceHandler(self)
 
         registerLiveDebugger(on_log=self.log)
@@ -418,7 +419,6 @@ class Application(BaseApplication):
             return
 
         # select the storage handler
-        client_handler = self.client_service_handler
         if state in (ClusterStates.RUNNING, ClusterStates.STARTING_BACKUP,
                      ClusterStates.BACKINGUP, ClusterStates.STOPPING_BACKUP):
             storage_handler = self.storage_service_handler
@@ -435,10 +435,13 @@ class Application(BaseApplication):
             conn = node.getConnection()
             conn.notify(notification_packet)
             if node.isClient():
-                if state != ClusterStates.RUNNING:
+                if state == ClusterStates.RUNNING:
+                    handler = self.client_service_handler
+                elif state == ClusterStates.BACKINGUP:
+                    handler = self.client_ro_service_handler
+                else:
                     conn.abort()
                     continue
-                handler = client_handler
             elif node.isStorage() and storage_handler:
                 handler = storage_handler
             else:

neo/master/handlers/client.py

@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from neo.lib.protocol import NodeStates, Packets, ProtocolError, MAX_TID
+from neo.lib.protocol import NodeStates, Packets, ProtocolError, MAX_TID, NotReadyError
 from . import MasterHandler
 
 class ClientServiceHandler(MasterHandler):
@@ -118,3 +118,18 @@ class ClientServiceHandler(MasterHandler):
         # BUG: The replicator may wait this transaction to be finished.
         self.app.tm.abort(tid, conn.getUUID())
 
+
+# like ClientServiceHandler but read-only
+class ClientROServiceHandler(ClientServiceHandler):
+
+    def _readOnly(self, *args, **kw):  raise NotReadyError('read-only access')
+
+    askBeginTransaction     = _readOnly
+    askNewOIDs              = _readOnly
+    askFinishTransaction    = _readOnly
+    askFinalTID             = _readOnly
+    askPack                 = _readOnly
+    abortTransaction        = _readOnly
+
+    # XXX also override askLastIDs to return backup_tid as last_tid ?
+    # XXX ----//---- askLastTransaction ?

neo/master/handlers/identification.py

@@ -41,9 +41,12 @@ class IdentificationHandler(MasterHandler):
 
         state = NodeStates.RUNNING
         if node_type == NodeTypes.CLIENT:
-            if app.cluster_state != ClusterStates.RUNNING:
+            if app.cluster_state == ClusterStates.RUNNING:
+                handler = app.client_service_handler
+            elif app.cluster_state == ClusterStates.BACKINGUP:
+                handler = app.client_ro_service_handler
+            else:
                 raise NotReadyError
-            handler = app.client_service_handler
             human_readable_node_type = ' client '
         elif node_type == NodeTypes.STORAGE:
             if app.cluster_state == ClusterStates.STOPPING_BACKUP: