API change: use default CCSID to run SQL queries when needed

[sebjulliand]

Changes

Running SQL queries in a job whose CCSID is 65535 is bad. This PR tries to avoid conversion errors by running a CHGJOB CCSID(xx) command before every SQL statement run through QZDFMDB2.

In above command, xx is the job's default CCSID which is retrieved at connection time (once then cached).

Noticeable changes:

• Default CCSID is retrieved using the ACTIVE_JOB SQL service. If it fails, we fall back to using DSPJOB OPTION(*DFNA) and parsing the output.
• the runSQL method has been simplified a bit. The logic to sanitize the statement about to be run has been put in a separate method in Tools and there is a unit test to check it.
• QZDFMDB2 allows to run CL command simply by prefixing them with @. It's convenient but it turns out such statements are always run in a separate job. So the method that sanitizes QZDFMDB2 statements will also rewrite every @command into Call QSYS2.QCMDEXC('command').
• A varchar conversion has been added in the getMemberList function to avoid a 1200 -> 65535 conversion issue, apparently unavoidable even with CHGJOB. The member's TEXT field is using CCSID 1200.
• The Default CCSID has been added to the Report Issue template. It is also reported in the Code for i output if QCCSID is bad.
  

Checklist

• have tested my change

[worksofliam]

Requested some changes, simple stuff mostly.

I would also appreciate an additional test for runSQL that includes running a CL command and then a statement.

Perhaps something like CHGLIBL and then select * from QSYS2. LIBRARY_LIST_INFO.

[sebjulliand]

Thanks @worksofliam !
I pushed a new test and the name modification. See my comment for your other comment.

[worksofliam]

This is a great test case!

[worksofliam]

@sebjulliand Before I leave my final review, I do think as part of this, before we release it especially, is that we should document this at a high level on our CCSID page. Something like... yep, we're setting the CCSID, but you really should set it on your user profile.

[sebjulliand]

@worksofliam agreed, and maybe add a button to open the URL on the notification that says naught-no-ccsid.

[worksofliam]

@sebjulliand Is that something you want to include in this PR or another time?

[worksofliam]

I am starting to wonder if this qccsid property should be renamed. Years ago we used to only check for QCCSID, but now we also store the job CCSID in this first.

What do you think?

[worksofliam]

Baring my two comments about:

1. When do we want to update the docs?
2. qccsid property name

The tests are passing and I am happy with the code.

[sebjulliand]

Thanks @worksofliam ! I'll merge now, and open another PR for renaming qccsid to something better and display a better error message when it is 65535.