Description:

Retrieves a file from HDFS. The content of the incoming FlowFile is replaced by the content of the file in HDFS. The file in HDFS is left intact without any changes being made to it.

Tags:

hadoop, hdfs, get, ingest, fetch, source

Properties:

In the list below, the names of required properties appear in bold. Any other properties (not in bold) are considered optional. The table also indicates any default values, and whether a property supports the Expression Language Guide.

Name	Default Value	Allowable Values	Description
Hadoop Configuration Resources			A file or comma separated list of files which contains the Hadoop file system configuration. Without this, Hadoop will search the classpath for a 'core-site.xml' and 'hdfs-site.xml' file or will revert to a default configuration.
Kerberos Principal			Kerberos principal to authenticate as. Requires nifi.kerberos.krb5.file to be set in your nifi.properties
Kerberos Keytab			Kerberos keytab associated with the principal. Requires nifi.kerberos.krb5.file to be set in your nifi.properties
Kerberos Relogin Period	4 hours		Period of time which should pass before attempting a kerberos relogin
HDFS Filename	${path}/${filename}		The name of the HDFS file to retrieve Supports Expression Language: true

Relationships:

Name	Description
failure	FlowFiles will be routed to this relationship if the content of the HDFS file cannot be retrieved and trying again will likely not be helpful. This would occur, for instance, if the file is not found or if there is a permissions issue
comms.failure	FlowFiles will be routed to this relationship if the content of the HDFS file cannot be retrieve due to a communications failure. This generally indicates that the Fetch should be tried again.
success	FlowFiles will be routed to this relationship once they have been updated with the content of the HDFS file

Reads Attributes:

None specified.

Writes Attributes:

Name	Description
hdfs.failure.reason	When a FlowFile is routed to 'failure', this attribute is added indicating why the file could not be fetched from HDFS

See Also:

ListHDFS,GetHDFS,PutHDFS