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.. _howto/connection:webhdfs:

Apache HDFS Connection
======================

The Apache HDFS connection type enables connection to Apache HDFS.

Default Connection IDs
----------------------

Web HDFS Hook uses parameter ``webhdfs_conn_id`` for Connection IDs and the value of the
parameter as ``webhdfs_default`` by default.

Configuring the Connection
--------------------------
Host
    The host to connect to, it can be ``local``, ``yarn`` or an URL. For Web HDFS Hook it is possible to specify multiple hosts as a comma-separated list.

Port
    Specify the port in case of host be an URL.

Login
    Effective user for HDFS operations (non-Kerberized).

Extra (optional, connection parameters)
    Specify the extra parameters (as json dictionary) that can be used in Web HDFS connection.
    The following extra parameters can be used to configure SSL for Web HDFS Hook:

    * ``use_ssl`` - If SSL should be used. By default is set to `false`.
    * ``verify`` - How to verify SSL. For more information refer to https://docs.python-requests.org/en/master/user/advanced/#ssl-cert-verification.
    * ``cert`` - Client certificate path for mTLS, can be combined cert or used with ``key``
    * ``key`` - Client key path for mTLS with ``cert``.
    * ``cookies`` - Add cookies to session.
    * ``headers`` - Add headers to session.
