Will Cloudpathlib support HDFS path?

[daviddwlee84]

I found that Cloudpathlib only supports prefixes with ['az://', 's3://', 'gs://'] currently.
Is there any plan to support HDFS path hdfs:// in the future?

[pjbull]

Hi @daviddwlee84, we're open to supporting HDFS as a provider. None of the core developers use it regularly, so it would be great to have it from a contributor.

A few questions:

• What's the best Python library for interacting with HDFS? There seem to be a quite a few options.
• Is there a good Dockerfile for a single-node HDFS deployment? We'll want testing infrastructure that's easy to maintain.

Otherwise, implementation will be creating the HdfsClient and HdfsPath like for the existing providers, a test rig, a mocked backend for unit testing, and any provider specific tests.

[daviddwlee84]

Thanks @pjbull, I see.

For the first question, as far as I know, pyarrow.fs.HadoopFileSystem might be a good choice. (Some other libraries are just wrapping up Hadoop CLI which requires complex environment setup and version matching.)

• Filesystem Interface
• pyarrow.fs.FileSelector

Here is an example of how fsspec manipulates this.

• fsspec.implementations.arrow
• API Reference

For the second question, I haven't used Hadoop within the container before.
I found this might be usable but not very active.
big-data-europe/docker-hadoop: Apache Hadoop docker image

For single-node deployment, this requires a matched Java & Hadoop version. With minimal configuration on $HADOOP_HOME/etc/hadoop/hdfs-site.xml like

<configuration>
    <property>
        <name>dfs.replication</name>
        <value>1</value>
    </property>
    <property>
        <name>dfs.namenode.name.dir</name>
        <value>file:///nvme/HDFS/HadoopName</value>
    </property>
    <property>
        <name>dfs.datanode.data.dir</name>
        <value>file:///nvme/HDFS/HadoopData</value>
    </property>
</configuration>

Then can start with $HADOOP_HOME/sbin/start-dfs.sh.
I think these installation steps can be done in a Dockerfile easily.