Add sanity-checks for keys to "kdb spec-mount" command

[qwepoizt]

Improves problems described in #3983 and #3987.

(This PR should not close these issues).

I've implemented several sanity checks in the spec-mounter.

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[qwepoizt]

@markus2330: I've implemented several sanity checks in the spec-mounter.

I think this is a good solution for #3987 and #3983: When someone creates a specification file and then executes kdb spec-mount ... to test/use it, they will receive errors if one of the sanity checks fails!

I think I can say from experience that these checks will help a lot, especially if someone is just getting started with Elektra/specification files. They cover the mistakes I made while writing the specification for redshift.

[markus2330]

Thank you very much for this improvement! Fixes for problems you actually ran into are very valuable. Nevertheless we should leave the issues open (or create new ones) as it would be better if such inconsistencies cannot happen at all (better design of the specification).

[qwepoizt]

Nevertheless we should leave the issues open.

Okay, I've edited the description of this PR so it won't auto close them!

[qwepoizt]

@markus2330: Currently, a test is failing in this PR, because I have not included "int" as an allowed value for the "type" metakey, but the following test uses a specification file with "type=int".

libelektra/tests/shell/gen/highlevel/nodefault.data.ini

Lines 1 to 5 in 5702ce0

	[]
	mountpoint=tests_gen_elektra_nodefault.ini
	[nodefault]
	type=int

Is "int" allowed?

• It is not documented in https://github.com/ElektraInitiative/libelektra/tree/master/doc/METADATA.ini
• It is used in a few places, e.g.:

libelektra/doc/METADATA.ini

Lines 356 to 357 in 90fb5be

	[args/index]
	type= int

libelektra/doc/METADATA.ini

Lines 77 to 80 in 90fb5be

	[order]
	type = int
	status = implemented
	usedby/plugin = hosts augeas toml

libelektra/doc/METADATA.ini

Lines 1191 to 1195 in 90fb5be

	[mode]
	status= deprecated
	type= int
	usedby/api= keyNew kdbextension.h
	description= The access mode of the key.

[qwepoizt]

@markus2330: Another check is also failing, namely the "Check" check:

doc/news/2018-11-18_0.8.25.md:343:0 http://coveralls.io
doc/news/2019-08-06_0.9.0.md:786:0 https://coveralls.io/github/ElektraInitiative/libelektra
doc/news/2020-05-26_0.9.2.md:274:0 https://coveralls.io/github/ElektraInitiative/libelektra
doc/news/2015-04-03_0.8.11.md:288:0 https://www.libelektra.org/ftp/elektra/pancheri2015gui.pdf
doc/news/2016-12-17_website_release.md:48:0 https://www.libelektra.org/ftp/elektra/mall2016rest.pdf
doc/news/2016-04-29_0.8.16.md:326:0 https://www.libelektra.org/ftp/elektra/berlakovich2016universal.pdf

• Have you maybe changed something on https://www.libelektra.org/ftp/elektra/ ?
• I also hope that coveralls.io will be back to service soon. It is in maintenance mode, responding with status 503 since Sep 17th. So far none of my PRs were blocked by this.
• Is there an alternative to removing the coverall links from the old release notes?

[markus2330]

Is "int" allowed?

No, this is probably some relic from before we started to use the CORBA type system. See doc/METADATA.ini for allowed types.

It is used in a few places, e.g.:

Thank you for pointing it out, these places need to be fixed!

Have you maybe changed something on https://www.libelektra.org/ftp/elektra/ ?

@robaerd pushed a new version which contains a commit that moves publications to a subfolder with that name. The links need to be corrected. I asked him to do that but it seems like he did not have time for this yet.

I also hope that coveralls.io will be back to service soon. It is in maintenance mode, responding with status 503 since Sep 17th. So far none of my PRs were blocked by this.

If some server is down (not Jenkins) there is nothing we can do about it, so we cannot let ourselves get blocked by this. The goal is to have as much functionality as possible in Jenkins. So we can merge your PRs if only non-Jenkins jobs fail.

[qwepoizt]

Thanks for your comment!

I've fixed the usage that made the test fail and created #4060 for a more detailed inspection of this. I've also marked it as "floss2021W", seems like a good issue to start!

I'll wait for the results of the checks.

[qwepoizt]

@markus2330: This is now ready to merge.

The 4 unsuccessful checks are caused by:

• 3 broken links, which will soon be updated (Add sanity-checks for keys to "kdb spec-mount" command #4058 (comment))
• An unrelated problem introduced in upstream glib (Use type metakey as fallback in range plugin #4055 (comment))

[markus2330]

Thank you very much! 💖