indexdb.py

import sqlite3


class IndexDB:
    """ Initialize index DB and connection. """

    def __init__(self):
        self.connection = self.initDB()

    def initDB(self):
        """ Connect to DB and init tables schema. """

        # Documents table schema.
        create_documents_table = '''CREATE TABLE IF NOT EXISTS documents
        (id VARCHAR(40) PRIMARY KEY, body LONGTEXT)'''
        # Documents words index schema.
        create_index_table = '''CREATE TABLE IF NOT EXISTS documents_words
        (id VARCHAR(40), word VARCHAR)'''
        # Document ID index to speed up word retrievals.
        create_index_table_index = '''CREATE INDEX IF NOT EXISTS
        document_id ON documents_words (id)'''

        # Connect to DB and create the tables.
        connection = sqlite3.connect('./index.sqlite')
        db = connection.cursor()
        # Create tables.
        db.execute(create_documents_table)
        db.execute(create_index_table)
        db.execute(create_index_table_index)
        return connection

    def handler(self):
        """ Return connection handler.  """
        return self.connection