Fix listing of files in AlluxioFileSystem

[awkwardd]

Description

When use alluxio as hive fs,cant get data from alluxio.
I finaly found that the AlluxioIterator.java didn't generate correct file location as alluxio://192...../dir/filename but alluxio:///dir/filename

Additional context and related issues

Fixes #23778

Release notes

( ) This is not user-visible or is docs only, and no release notes are required.
( ) Release notes are required. Please propose a release note for me.
(x) Release notes are required, with the following suggested text:

## Hive
* Fix reading from tables when using alluxio filesystem. ({issue}`23815`)

[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: tanyajun.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email [email protected]
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[raunaqmorarka]

Could you add a test for this problem ?

[JiamingMai]

@awkwardd Add the following extractSchema method to AlluxioUtils, and update the next() method in AlluxioFileIterator can pass the test successfully. Please help update the code in this PR.

    public static Location extractSchema(Location location)
    {
        String path = location.toString();
        if (path.startsWith("alluxio://")) {
            int index = path.indexOf("/", "alluxio://".length());
            if (index != -1) {
                String schema = path.substring(0, index);
                return Location.of(schema + "/");
            }
            else {
                return location;
            }
        }
        return location;
    }

   public FileEntry next()
            throws IOException
    {
        if (!hasNext()) {
            return null;
        }
        URIStatus fileStatus = files.next();
        String path = fileStatus.getPath();
        if (path.startsWith("/")) {
            path = path.substring(1);
        }
        Location schema = extractSchema(dirLocation);
        Location fileLocation = schema.appendSuffix(path);
        return new FileEntry(
                fileLocation,
                fileStatus.getLength(),
                Instant.ofEpochMilli(fileStatus.getLastModificationTimeMs()),
                Optional.empty());
    }

[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: tanyajun.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email [email protected]
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[JiamingMai]

@awkwardd you may also need to sign the CLA https://trino.io/development/process#contribution-process

[awkwardd]

@awkwardd you may also need to sign the CLA https://trino.io/development/process#contribution-process

I have signed the cla file and snet it last night.

[ebyhr]

@cla-bot check

[cla-bot]

Thank you for your pull request and welcome to our community. We could not parse the GitHub identity of the following contributors: tanyajun.
This is most likely caused by a git client misconfiguration; please make sure to:

1. check if your git client is configured with an email to sign commits git config --list | grep email
2. If not, set it up using git config --global user.email [email protected]
3. Make sure that the git commit email is configured in your GitHub account settings, see https://github.com/settings/emails

[cla-bot]

The cla-bot has been summoned, and re-checked this pull request!

[ebyhr]

@awkwardd Please take a look at #23815 (comment)

[JiamingMai]

This change looks good to me. @raunaqmorarka Could you help merge this PR?

[raunaqmorarka]

This change looks good to me. @raunaqmorarka Could you help merge this PR?

Can we add a test here ? The existing tests didn't catch this right ?

[github-actions]

This pull request has gone a while without any activity. Tagging for triage help: @mosabua