[TASK] Add CitaviProject class, integrate first handling for uploaded projects.

frontend/views.py

@@ -125,20 +125,37 @@ class UpdateProjectView(ProtectedFormView, SingleObjectMixin):
         self.success_url = self.success_url + self.project_id + '/update'
         return super(UpdateProjectView, self).post(request, *args, **kwargs)
     
-    """ This form_valid handles the file uploads and triggers a citavi schema import and things. """
     def form_valid(self, form, *args, **kwargs):
+        """ This form_valid handles the file upload. """
         original_file = form.files[u'file']
         original_filename = str(original_file)
-        relative_path = default_storage.save('tmp/project_' + self.project_id + '.ctt4', ContentFile(original_file.read()))
-        path = os.path.join(settings.MEDIA_ROOT, relative_path)
         
-        #TODO: Actually validate that we get an SQLite3 file!
+        """ Put file into temporary folder for analysis """
+        relative_path = default_storage.save('tmp/project_' + str(self.project_id) + '.ctt4', ContentFile(original_file.read()))
+        temp_sqlite = os.path.join(settings.MEDIA_ROOT, relative_path)
         
-        # Store this in the project model
+        """ Test if SQLite is a valid citavi project. """
+        from service import Citavi
+        citavi_project = Citavi.CitaviProject(temp_sqlite)
+        citavi_project_valid = citavi_project.is_valid()
+        """ Free temporary ressources. """
+        del citavi_project
+        default_storage.delete(temp_sqlite)
+        
+        if citavi_project_valid == False:
+            """ TODO: Put up an error message or something. """
+            pass
+        else:            
+            """ Actually store file in citavi folder """
+            relative_path = default_storage.save('citavi/project_' + str(self.project_id) + '.ctt4', ContentFile(original_file.read()))
+            sqlite_path = os.path.join(settings.MEDIA_ROOT, relative_path)
+
+            """ Store new original filename in Project """
             project = Project.objects.get(id=self.project_id)
             project.associated_filename = original_filename
             project.save()
             
+            """ Refresh identities from citavi project. """
+            # TODO
         return super(UpdateProjectView, self).form_valid(form)
 
-        

service/Citavi.py

@@ -1,7 +1,80 @@
 # -*- coding: utf-8 -*-
 
+from sqlalchemy import create_engine,  MetaData
+from sqlalchemy.ext.automap import automap_base
+from sqlalchemy.orm import Session
 
 
+class CitaviProject():
+    """ A helper class representing a Citavi project. """
+    def __init__(self, sqlite_file):
+        """ Constructor to get absolute path to sqlite. """
+        self.sqlite_file = sqlite_file
+        self._is_open = False
+        self._is_error = False
+        self._sa = {} # Object namespace for sqlalchemy related objects
+        
+    def __del__(self):
+        """ Destructor to close the citavi file. """
+        self.close()
+
+    def is_valid(self):
+        """ This method returns False in case the given sqlite file is not a valid Citavi project. """
+        self.open()
+        return self._is_open and not self._is_error
+
+    def get_persons(self):
+        try:
+            PersonClass = self._sa_sqlite_autobase.classes.Person
+        except:
+            return False
+
+    def open(self):
+        """ Public method to open a citavi project file. """
+        if not self._is_open:
+            self._open()
+
+    def close(self):
+        """ Public method to close a citavi project file. """
+        if self._is_open:
+            self._close()
+
+    def _open(self):
+        """ Internal method to open a citavi project file. """
+        try:
+            self._sa_sqlite_engine = create_engine('sqlite+pysqlite:///' + self.sqlite_file)
+            self._sa_sqlite_session = Session(self._sa_sqlite_engine)
+            self._sa_sqlite_meta = MetaData(bind=self._sa_sqlite_engine)
+            self._sa_sqlite_meta.reflect()
+            self._sa_sqlite_autobase = automap_base()
+            self._sa_sqlite_autobase.prepare(self._sa_sqlite_engine, reflect=True)
+            self._is_open = True
+        except:
+            self._is_error = True
+            self._is_open = False
+
+    def _close(self):
+        """ Internal method to actually close a citavi project file. """
+        try:
+            del self._sa.sqlite_engine
+            del self._sa.sqlite_session
+            del self._sa.sqlite_meta
+            del self._sa.sqlite_autobase
+            del self._sa.sqlite_engine
+            self._is_open = False
+        except:
+            self._is_error = True
+            self._is_open = True
+
+
+
+    pass
+
+
+
+
+
+"""
 
 def import_sqlite(project_id, sqlite_file):
     print "This is import_sqlite speaking!"
@@ -9,11 +82,6 @@ def import_sqlite(project_id, sqlite_file):
     print sqlite_file
     print "Importing data..."
         
-    from sqlalchemy import *
-    from sqlalchemy.schema import CreateSchema
-    from sqlalchemy.ext.automap import automap_base
-    from sqlalchemy.orm import Session
-    
     # Initialize sqlite part
     sqlite_engine = create_engine('sqlite+pysqlite:///project_import_9.ctt4', echo=True)
     sqlite_session = Session(sqlite_engine)
@@ -26,11 +94,9 @@ def import_sqlite(project_id, sqlite_file):
     psql_engine.execute(CreateSchema('alchemytest')) # TODO: Catch Exception/Warning/Whatever here
     psql_meta = MetaData(bind=psql_engine, schema='alchemytest')
     
-    """
     # Reflect the origin - maybe psql_meta.reflect() is enough?
     sqlite_autobase = automap_base()
     sqlite_autobase.prepare(sqlite_engine, reflect=True)
-    """
     
     
     # This small snippet prints python class code for sqlalchemy reflected classes
@@ -59,7 +125,6 @@ def import_sqlite(project_id, sqlite_file):
     #meta.tables['ReferenceAuthor'].select().execute().fetchall()
     
     # Now we need to "convert" unsupported types :-/
-    """
     for table in meta.sorted_tables:
         table_name = str(table)
         columns = table.columns.items()
@@ -71,9 +136,3 @@ def import_sqlite(project_id, sqlite_file):
         print
     print
 """
-    
-    """ TODO: since DATETIME (sqlite3) does not map onto TIMESTAMP / DATE (postgresql), some mapping/migrating is required! """
-    
-
-
-    pass