citavi_mapper/service/sqlitehelper.py

# -*- coding: utf-8 -*-




def import_sqlite(project_id, sqlite_file):
    print "This is import_sqlite speaking!"
    print project_id
    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)
    sqlite_meta = MetaData(bind=sqlite_engine)
    sqlite_meta.reflect()
    
    # Initialize postresql part
    psql_engine = create_engine("postgresql://citavi_mapper:foobar2000@localhost:5432/citavi_mapper")
    psql_session = Session(psql_engine)
    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
    for table in sqlite_meta.sorted_tables:
        table_name = str(table)
        columns = table.columns.items()
        print "class " + table_name + "(Base):"
        print "    __tablename__ = '" + table_name + "'"
        print
        for column_tuple in columns:
            column_name = column_tuple[0]
            actual_sqlalchemy_column = column_tuple[1]
            column_type = str(vars(actual_sqlalchemy_column)['type'])
            column_type = str(vars(actual_sqlalchemy_column)['type'])
            #print table_name + "." + column_name + ': ' + column_type
            print "    " + column_name + " = Column(" + column_type + ")"
        print
        print
        
    # Shove it up into postgresql's ... you know.
    psql_meta.create_all(psql_engine)
    
    #sqlite_meta.reflect()
    
    #meta.tables['Reference']
    #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()
        for column_tuple in columns:
            column_name = column_tuple[0]
            actual_sqlalchemy_column = column_tuple[1]
            column_type = str(vars(actual_sqlalchemy_column)['type'])
            print table_name + "." + column_name + ': ' + column_type
        print
    print
    """
    
    """ TODO: since DATETIME (sqlite3) does not map onto TIMESTAMP / DATE (postgresql), some mapping/migrating is required! """
    


    pass