HPCC-16077 Add option to download WU result in CSV format

[wangkx]

The option can be used by WsWorkunits.WUResultBin.format = 'csv'.

Signed-off-by: wangkx kevin.wang@lexisnexis.com

[hpcc-jirabot]

https://track.hpccsystems.com/browse/HPCC-16077
Jira updated

[wangkx]

@afishbeck please review

[afishbeck]

Are you sure you can rely on the fieldname "row" not being used for other types of fields. And is this processing post xpath, where a row might have another name? i.e.

<Records>
<Record>

Rather than
<Records>
<Row>
?

[afishbeck]

@wangkx I think I need to step through an example before I can continue much further.

[afishbeck]

@wangkx testing looked ok when I didn't use xpaths on the datasets.. but I'll wait until you fix that (as we discussed) before continuing to review the code.

Here's some code I threw together to test. Take out all the XPATHs and run it once. I think it will work ok. Then run with the xpaths and debug. Notice the xpath('/Name').. that's a different variation then just renaming the 'Row'. If you need help let me know. You can look at the legacy eclwatch view to get a good idea of what it should look like.

`namerec := RECORD
string First {xpath('First')};
string Last {xpath('Last')};
END;

Addressrec := RECORD
string city {xpath('City')};
string zip {xpath('ZipCode')};
END;

bestrec := RECORD
namerec name {xpath('Name')};
addressrec address {xpath('Address')};
END;

Personrec := RECORD
bestrec best;
dataset(namerec) names {xpath('/Name')};
dataset(addressrec) addresses {xpath('Addresses/Address')};
dataset(namerec) Aliases;
END;

Peoplerec := RECORD
dataset(Personrec) addresses {xpath('Persons/Person')};
END;

ds := dataset([{[{{{'A', 'B'},{'C', 'Z'}}, [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}], [{'C1', 'Z1'},{'C2', 'Z2'},{'C3', 'Z2'}], [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}]},{{{'A', 'B'},{'C', 'Z'}}, [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}], [{'C1', 'Z1'},{'C2', 'Z2'},{'C3', 'Z2'}], [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}]},{{{'A', 'B'},{'C', 'Z'}}, [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}], [{'C1', 'Z1'},{'C2', 'Z2'},{'C3', 'Z2'}], [{'Aa', 'Bb'},{'Ab', 'Bc'},{'Ac', 'Bd'}]}]}], Peoplerec);

output(ds, named('People'));`

[wangkx]

The latest code should handle both xpath and no xpath. It still needs to be cleaned.

[richardkchapman]

@afishbeck Please re-review

[afishbeck]

@wangkx Let me know when you've finished the changes you mentioned.

[wangkx]

@afishbeck the code has been cleaned. Please review.

[HPCCSmoketest]

Automated Smoketest
Sha: 807f0a9
Build: success
Install hpccsystems-platform-community_6.1.0-trunk0.el6.x86_64.rpm
HPCC Start: OK
Unittest result: total:83 passed:83 failed:0

HPCC Stop: OK
HPCC Uninstall: OK

[afishbeck]

Don't forget to remind Gordon that it needs to be integrated into the UI.

[wangkx]

@GordonSmith or @miguelvazq you may need to add an option to download WU Result csv to ECLWatch UI: https://track.hpccsystems.com/browse/HPCC-16325.

@richardkchapman this PR is ready to be merged.