Coverage for airflow.hooks.base_hook : 49%

from __future__ import absolute_import 

from __future__ import division 

from __future__ import print_function 

from __future__ import unicode_literals 

from builtins import object 

import logging 

import os 

import random 

from airflow import settings 

from airflow.models import Connection 

from airflow.utils import AirflowException 

CONN_ENV_PREFIX = 'AIRFLOW_CONN_' 

class BaseHook(object): 

    """ 

    Abstract base class for hooks, hooks are meant as an interface to 

    interact with external systems. MySqlHook, HiveHook, PigHook return 

    object that can handle the connection and interaction to specific 

    instances of these systems, and expose consistent methods to interact 

    with them. 

    """ 

    def __init__(self, source): 

        pass 

    @classmethod 

    def get_connections(cls, conn_id): 

        session = settings.Session() 

        db = ( 

            session.query(Connection) 

            .filter(Connection.conn_id == conn_id) 

            .all() 

        ) 

        if not db: 

            raise AirflowException( 

                "The conn_id `{0}` isn't defined".format(conn_id)) 

        session.expunge_all() 

        session.close() 

        return db 

    @classmethod 

    def get_connection(cls, conn_id): 

        environment_uri = os.environ.get(CONN_ENV_PREFIX + conn_id.upper()) 

        conn = None 

        if environment_uri: 

            conn = Connection(uri=environment_uri) 

        else: 

            conn = random.choice(cls.get_connections(conn_id)) 

        if conn.host: 

            logging.info("Using connection to: " + conn.host) 

        return conn 

    @classmethod 

    def get_hook(cls, conn_id): 

        connection = cls.get_connection(conn_id) 

        return connection.get_hook() 

    def get_conn(self): 

        raise NotImplementedError() 

    def get_records(self, sql): 

        raise NotImplementedError() 

    def get_pandas_df(self, sql): 

        raise NotImplementedError() 

    def run(self, sql): 

        raise NotImplementedError()