Very first incomplete draft of ClusterComm.

Note that this is not yet in the Makefiles, but it at least compiles
if one puts it there.

arangod/Cluster/ClusterComm.cpp

@@ -0,0 +1,45 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief Library for intra-cluster communications
+///
+/// @file ClusterComm.cpp
+///
+/// DISCLAIMER
+///
+/// Copyright 2010-2013 triagens GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Max Neunhoeffer
+/// @author Copyright 2013, triagens GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+#include <arangod/Cluster/ClusterComm.h>
+
+using namespace triagens::arango;
+
+// -----------------------------------------------------------------------------
+// --SECTION--
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief
+////////////////////////////////////////////////////////////////////////////////
+
+// Local Variables:
+// mode: outline-minor
+// outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @\\}\\)"
+// End:
+
+

arangod/Cluster/ClusterComm.h

@@ -0,0 +1,196 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief Library for intra-cluster communications
+///
+/// @file ClusterComm.h
+///
+/// DISCLAIMER
+///
+/// Copyright 2010-2013 triagens GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Max Neunhoeffer
+/// @author Copyright 2013, triagens GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef TRIAGENS_CLUSTER_COMM_H
+#define TRIAGENS_CLUSTER_COMM_H 1
+
+#include "Basics/Common.h"
+#include "Basics/ReadWriteLock.h"
+#include "Rest/HttpRequest.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+namespace triagens {
+  namespace arango {
+
+    typedef string ClientTID;
+    typedef string CoordTID;
+    typedef int32_t OpID;
+    typedef string ShardID;
+    typedef string ServerID;
+
+    class ClusterCommResult {
+      OpID opID;
+      // All the stuff from the HTTP request result
+
+    };
+
+    class ClusterCommCallback {
+      // The idea is that one inherits from this class and implements
+      // the callback.
+
+      ClusterCommCallback();
+      ~ClusterCommCallback();
+
+      // Result indicates whether or not the returned result shall be queued
+      virtual bool operator() (ClusterCommResult *);
+    };
+
+    typedef uint64_t ClusterCommTimeout;    // in microseconds
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                      ClusterComm
+// -----------------------------------------------------------------------------
+
+    class ClusterComm {
+      
+// -----------------------------------------------------------------------------
+// --SECTION--                                     constructors and destructors
+// -----------------------------------------------------------------------------
+      
+      public:
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief initialises library
+////////////////////////////////////////////////////////////////////////////////
+      
+        ClusterComm ( );
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief shuts down library
+////////////////////////////////////////////////////////////////////////////////
+      
+        ~ClusterComm ( );
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                   public methods
+// -----------------------------------------------------------------------------
+      
+////////////////////////////////////////////////////////////////////////////////
+/// @brief produces an operation ID which is unique in this process
+////////////////////////////////////////////////////////////////////////////////
+      
+        OpID getOpID ( );
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief submit an HTTP request to a shard synchronously
+////////////////////////////////////////////////////////////////////////////////
+
+        int request (const ClientTID& clientTID,
+                     const CoordTID&  coordTID,
+                     const OpID& opID,
+                     const ShardID& shardID,
+                     rest::HttpRequest::HttpRequestType reqtype,
+                     const string& path,
+                     const char* body,
+                     size_t bodyLength,
+                     const map<string, string>& headerFields,
+                     ClusterCommCallback* callback,
+                     ClusterCommTimeout& timeout);
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief poll one answer for a given opID
+////////////////////////////////////////////////////////////////////////////////
+
+        ClusterCommResult* poll (const ClientTID& clientTID,
+                                 const CoordTID&  coordTID,
+                                 const OpID&      opID, 
+                                 const ShardID&   shardID,
+                                 bool blocking = false, 
+                                 ClusterCommTimeout timeout = 0);
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief poll many answers for some given opIDs
+////////////////////////////////////////////////////////////////////////////////
+
+        vector<ClusterCommResult*> multipoll (
+                const ClientTID& clientTID,
+                const CoordTID&  coordTID,
+                const OpID&      opID, 
+                const ShardID&   shardID,
+                int maxanswers = 0,
+                bool blocking = false,
+                ClusterCommTimeout timeout = 0);
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief ignore and drop current and future answers
+////////////////////////////////////////////////////////////////////////////////
+
+        void drop (const ClientTID& clientTID,
+                   const CoordTID&  coordTID,
+                   const OpID&      opID, 
+                   const ShardID&   shardID);
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief send an answer HTTP request to a coordinator
+////////////////////////////////////////////////////////////////////////////////
+                
+        int answer (rest::HttpRequest& request,
+                    rest::HttpRequest::HttpRequestType reqtype,
+                    const string& path,
+                    const char* body,
+                    size_t bodyLength,
+                    const map<string, string>& headerFields,
+                    ClusterCommTimeout& timeout);
+                 
+// -----------------------------------------------------------------------------
+// --SECTION--                                                     private data
+// -----------------------------------------------------------------------------
+
+       private: 
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief process global last used operation ID
+////////////////////////////////////////////////////////////////////////////////
+
+         static OpID _lastUsedOpID;
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief global lock to protect _lastUsedOpID
+////////////////////////////////////////////////////////////////////////////////
+
+         static triagens::basics::ReadWriteLock _lock;
+
+    };  // end of class ClusterComm
+
+  }  // namespace arango
+}  // namespace triagens
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+// Local Variables:
+// mode: outline-minor
+// outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @\\}\\)"
+// End:
+
+