First attempt of adding UpdateDBConnection

docs.md/Creating_the_wheel.md

@@ -7,6 +7,7 @@ older Linux distributions.
 Indeed, PyPI forbids uploading wheel that do not specify a compatibility tag
 used to choose the right wheel when running `pip install SQLamarr`.
 
+## Using docker 
 To compile the wheel in compatibility mode, we are using the following recipe,
 which assumes the working directory is the root of the git repository
 ```bash
@@ -15,7 +16,22 @@ docker run -it -v $PWD:/mylib quay.io/pypa/manylinux2014_x86_64:latest \
 python3 -m twine upload wheelhouse/*.whl
 ```
 
-Additional information:
+## Using Apptainer
+In some environments, docker is not available and apptainer should be used instead.
+
+First convert the docker image to an SIF image (this is only required once). 
+```bash
+apptainer build /tmp/pypa.sif docker://quay.io/pypa/manylinux2014_x86_64:latest
+```
+
+Then execute the following script (as for the docker case, it is assumed 
+the working directory is the root of the git repository).
+
+```build
+apptainer exec --bind $PWD:/mylib --writable-tmpfs /tmp/pypa.sif /bin/bash make_wheel.sh
+```
+
+## Additional information:
  * Distributing binaries in compatibility mode: https://github.com/pypa/manylinux
  * Example using travis for CI/CD: https://github.com/pypa/python-manylinux-demo
 

include/SQLamarr/BaseSqlInterface.h

@@ -13,7 +13,6 @@
 #include <string>
 #include <unordered_map>
 
-#include "SQLamarr/BaseSqlInterface.h"
 #include "SQLamarr/db_functions.h"
 
 namespace SQLamarr

include/SQLamarr/UpdateDBConnection.h

@@ -0,0 +1,54 @@
+// (c) Copyright 2022 CERN for the benefit of the LHCb Collaboration.
+//
+// This software is distributed under the terms of the GNU General Public
+// Licence version 3 (GPL Version 3), copied verbatim in the file "LICENCE".
+//
+// In applying this licence, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#pragma once
+
+// STL
+#include <string>
+
+// SQLamarr
+#include "SQLamarr/db_functions.h"
+#include "SQLamarr/Transformer.h"
+
+namespace SQLamarr
+{
+  /** Reset the database connection forcing flushing the db status.
+   *
+   * In the interaction with Python or other frameworks it is sometimes
+   * necessary to ensure db synchronization with disk or shared memory.
+   * This can be achieved refreshing the connection to the database, 
+   * by closing it and reopening. 
+   *
+   * WARNING! Executing UpdateDBConnection drops TEMPORARY tables and views. 
+   */
+  class UpdateDBConnection: public Transformer
+  {
+    public:
+      /// Constructor
+      UpdateDBConnection (
+          SQLite3DB& db, 
+            ///< Reference to the database
+          std::string filename,
+            ///< Filename or URI of the (possibly new) connection to the database
+          int flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_URI
+            ///< Flags
+          );
+
+
+      /// Execute the algorithm, cleaning the database 
+      void execute () override;
+
+    private: // members
+      SQLite3DB& m_database; ///< Reference to the SQLite database (not owned).
+      const std::string m_filename; ///< Filename or URI of the database
+      const int m_flags; ///< SQLite flags to open to database (see sqlite_open_v3)
+  };
+}
+
+

make_wheel.sh

@@ -7,7 +7,7 @@ cd /mylib;
 rm -f wheelhouse/*.whl | echo "Ok";
 rm -f dist/*.whl | echo "Ok";
 
-for PYVERSION in cp311-cp311 cp310-cp310 cp37-cp37m cp38-cp38 cp39-cp39;
+for PYVERSION in cp312-cp312 cp311-cp311 cp310-cp310 cp37-cp37m cp38-cp38 cp39-cp39;
 do
   export PYBIN=/opt/python/$PYVERSION/bin/python3
   echo "Preparing binary distribution with $PYBIN";

python/SQLamarr/db_functions.py

@@ -61,6 +61,10 @@ def __del__(self):
         """@private: Return the raw pointer to the algorithm."""
         clib.del_database(self._pointer)
 
+    @property
+    def path(self):
+      return self._path
+
     def get(self):
         """@private: Return the raw pointer to the database."""
         return self._pointer

src/UpdateDBConnection.cpp

@@ -0,0 +1,45 @@
+// (c) Copyright 2022 CERN for the benefit of the LHCb Collaboration.
+//
+// This software is distributed under the terms of the GNU General Public
+// Licence version 3 (GPL Version 3), copied verbatim in the file "LICENCE".
+//
+// In applying this licence, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+
+// STL
+#include <memory>
+
+// SQLite3
+#include "sqlite3.h"
+
+// SQLamarr
+#include "SQLamarr/UpdateDBConnection.h"
+
+namespace SQLamarr
+{
+  //============================================================================
+  // Constructor
+  //============================================================================
+  UpdateDBConnection::UpdateDBConnection(
+      SQLite3DB& db,
+      std::string filename,
+      int flags
+      )
+    : m_database(db)
+    , m_filename(filename)
+    , m_flags(flags)
+  {}
+
+  //============================================================================
+  // execute
+  //============================================================================
+  void UpdateDBConnection::execute()
+  {
+    SQLite3DB new_database = make_database(m_filename, m_flags);
+    m_database.swap(new_database);
+  }
+}
+
+

src/python_bindings.cpp

@@ -23,6 +23,7 @@
 #include "SQLamarr/TemporaryTable.h"
 #include "SQLamarr/CleanEventStore.h"
 #include "SQLamarr/EditEventStore.h"
+#include "SQLamarr/UpdateDBConnection.h"
 #include "SQLamarr/SQLiteError.h"
 
 constexpr int SQL_ERRORSHIFT = 10000;
@@ -39,6 +40,7 @@ typedef enum {
     , TemporaryTable
     , CleanEventStore
     , EditEventStore
+    , UpdateDBConnection
   } TransformerType;
 
 struct TransformerPtr {
@@ -254,6 +256,19 @@ TransformerPtr new_EditEventStore (
     )};
 }
 
+//==============================================================================
+// UpdateDBConnection
+//==============================================================================
+extern "C"
+TransformerPtr new_UpdateDBConnection (
+    void *db, 
+    const char* path
+    )
+{
+  SQLite3DB *udb = reinterpret_cast<SQLite3DB *>(db);
+  return {UpdateDBConnection, new SQLamarr::UpdateDBConnection(*udb, path)};
+}
+
 //==============================================================================
 // Delete Transformer
 //==============================================================================
@@ -286,6 +301,9 @@ void del_Transformer (TransformerPtr self)
     case EditEventStore:
       delete reinterpret_cast<SQLamarr::EditEventStore*> (self.p);
       break;
+    case UpdateDBConnection:
+      delete reinterpret_cast<SQLamarr::UpdateDBConnection*> (self.p);
+      break;
     default:
       throw std::bad_cast();
   }