Fix LaTeXML snap package publish error

[ronaldtse]

The resolution seems to be this: electron-userland/electron-builder#3608 (comment)

The original issue seems to be:

For some reasons the setguid flag is set on the home directory and all subdirectories inherit the flag...

The resolution seems to be: reset chmod on all built files right before packaging.

Look at develar/app-builder@b34fa7d#diff-610408e9d8c7bf76507a8148ea6e10b3R263

(

	// https://github.com/electron-userland/electron-builder/issues/3608
 	// even if electron-builder will correctly unset setgid/setuid, still, quite a lot of possibilities for user to create such incorrect permissions,
 	// so, just unset it using chmod right before packaging
 	dirs := []string{stageDir, *options.appDir, templateDir}
 	err = util.MapAsync(len(dirs), func(taskIndex int) (func() error, error) {
 		dir := dirs[taskIndex]
 		return func() error {
 			_, err := util.Execute(exec.Command("chmod", "-R", "g-s", dir), dir)
 			if err != nil {
 				log.WithError(err).Warn("cannot execute chmod")
 			}
 			return nil
 		}, nil
 	})

  	if err != nil {
 		return errors.WithStack(err)
 	}

)

https://travis-ci.com/metanorma/latexml-snap/builds/128696040

Full trace:

Using local configuration ('.snapcraft/snapcraft.cfg'), changes will not be persisted.
1248
1249Login successful. You now have these capabilities:
1250
1251snaps:       ['latexml']
1252channels:    ['edge']
1253permissions: ['package_access', 'package_push', 'package_release']
1254expires:     2020-09-21T23:56:22.406272
1255
1256Preparing to push 'latexml_fixed.snap'.
1257After pushing, an attempt will be made to release to 'edge'
1258Using local configuration ('.snapcraft/snapcraft.cfg'), changes will not be persisted.
1259Using local configuration ('.snapcraft/snapcraft.cfg'), changes will not be persisted.
1260Pushing 'latexml_fixed.snap' [===========================================] 100%
1261Processing...|                                                                 
1262Error while processing...
1263The store was unable to accept this snap.
1264  - found errors in file output: unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml', unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml/declaration', unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml/dtd', unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml/entities', unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml/misc', unusual mode 'rwxrwsr-x' for entry './usr/local/share/sgml/stylesheet', unusual mode 'rwxrwsr-x' for entry './usr/local/share/xml', unusual mode 'rwxrwsr-x' for entry './usr/local/share/xml/declaration', unusual mode 'rwxrwsr-x' for entry './usr/local/share/xml/entities', unusual mode 'rwxrwsr-x' for entry './usr/local/share/xml/misc', unusual mode 'rwxrwsr-x' for entry './usr/local/share/xml/schema'
1265  - checksums do not match. Please ensure the snap is created with either 'snapcraft pack <DIR>' (using snapcraft >= 2.38) or 'mksquashfs <dir> <snap> -noappend -comp xz -all-root -no-xattrs -no-fragments'. If using electron-builder, please upgrade to latest stable (>= 20.14.7). See https://forum.snapcraft.io/t/automated-reviews-and-snapcraft-2-38/4982/17 for details.
1266Script failed with status 2
1267
1268

[ronaldtse]

Still failing in the latest build:

checksums do not match. Please ensure the snap is created with either 'snapcraft pack <DIR>' (using snapcraft >= 2.38) or 'mksquashfs <dir> <snap> -noappend -comp xz -all-root -no-xattrs -no-fragments'. If using electron-builder, please upgrade to latest stable (>= 20.14.7). See https://forum.snapcraft.io/t/automated-reviews-and-snapcraft-2-38/4982/17 for details. security-snap-v2_squashfs_repack_checksum What does this mean?
found errors in file output: unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml', unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml/declaration', unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml/dtd', unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml/entities', unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml/misc', unusual mode 'rwxr-sr-x' for entry './usr/local/share/sgml/stylesheet', unusual mode 'rwxr-sr-x' for entry './usr/local/share/xml', unusual mode 'rwxr-sr-x' for entry './usr/local/share/xml/declaration', unusual mode 'rwxr-sr-x' for entry './usr/local/share/xml/entities', unusual mode 'rwxr-sr-x' for entry './usr/local/share/xml/misc', unusual mode 'rwxr-sr-x' for entry './usr/local/share/xml/schema' security-snap-v2_squashfs_files

[CAMOBAP]

Probably we will need rewrite snap according to suggestions here:

• https://forum.snapcraft.io/t/struggling-with-packaging-a-very-simple-perl-script/12163/3
• https://forum.snapcraft.io/t/the-perl-launch-stage-snap/11736
• https://forum.snapcraft.io/t/the-debian-multiarch-triplet-provider-launch-stage-snap/11738

[ronaldtse]

@CAMOBAP795 sounds good, let's proceed!

[CAMOBAP]

@ronaldtse released https://snapcraft.io/latexml

[ronaldtse]

@CAMOBAP795 amazing, thank you for this!