Source code for airflow.hooks.hdfs_hook

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from six import PY2

from airflow import configuration
from airflow.exceptions import AirflowException
from airflow.hooks.base_hook import BaseHook

snakebite_imported = False
if PY2:
    from snakebite.client import Client, HAClient, Namenode, AutoConfigClient
    snakebite_imported = True

class HDFSHookException(AirflowException):

[docs]class HDFSHook(BaseHook): """ Interact with HDFS. This class is a wrapper around the snakebite library. :param hdfs_conn_id: Connection id to fetch connection info :type conn_id: string :param proxy_user: effective user for HDFS operations :type proxy_user: string :param autoconfig: use snakebite's automatically configured client :type autoconfig: bool """ def __init__(self, hdfs_conn_id='hdfs_default', proxy_user=None, autoconfig=False): if not snakebite_imported: raise ImportError( 'This HDFSHook implementation requires snakebite, but ' 'snakebite is not compatible with Python 3 ' '(as of August 2015). Please use Python 2 if you require ' 'this hook -- or help by submitting a PR!') self.hdfs_conn_id = hdfs_conn_id self.proxy_user = proxy_user self.autoconfig = autoconfig
[docs] def get_conn(self): """ Returns a snakebite HDFSClient object. """ # When using HAClient, proxy_user must be the same, so is ok to always # take the first. effective_user = self.proxy_user autoconfig = self.autoconfig use_sasl = configuration.conf.get('core', 'security') == 'kerberos' try: connections = self.get_connections(self.hdfs_conn_id) if not effective_user: effective_user = connections[0].login if not autoconfig: autoconfig = connections[0].extra_dejson.get('autoconfig', False) hdfs_namenode_principal = connections[0].extra_dejson.get( 'hdfs_namenode_principal') except AirflowException: if not autoconfig: raise if autoconfig: # will read config info from $HADOOP_HOME conf files client = AutoConfigClient(effective_user=effective_user, use_sasl=use_sasl) elif len(connections) == 1: client = Client(connections[0].host, connections[0].port, effective_user=effective_user, use_sasl=use_sasl, hdfs_namenode_principal=hdfs_namenode_principal) elif len(connections) > 1: nn = [Namenode(, conn.port) for conn in connections] client = HAClient(nn, effective_user=effective_user, use_sasl=use_sasl, hdfs_namenode_principal=hdfs_namenode_principal) else: raise HDFSHookException("conn_id doesn't exist in the repository " "and autoconfig is not specified") return client