Update README.Maintainer to match current best practices

debian/README.Maintainer

-# README for Debian package maintainers #
+# README for Debian package maintainers
 
 This file mostly applies to how the packaging work-flow works for the official
 Debian packages, but it may contain useful information also for anybody doing
 their own private .deb builds.
 
+## Version control
 
-## Building from sources with git-buildpackage ##
-
-Clone sources with all branches
-  sudo apt-get install git-buildpackage
-  gbp-clone --pristine-tar git://git.debian.org/git/pkg-mysql/mariadb-10.1.git
-
-Alternatively use Github mirror at https://github.com/ottok/mariadb-10.1.git
+This package is maintained by the MariaDB/MySQL team in Debian using the
+git-buildpackage tool and storing the git repositories on the Debian Gitlab
+instance Salsa. For details see https://salsa.debian.org/mariadb-team/.
 
-On later runs make sure to have latest version of sources
-  gbp-pull --pristine-tar --force
+The official Ubuntu packages are also maintained by the same team using the same
+source repository.
 
+### Ensuring git contents match what has been uploaded to Debian/Ubuntu
 
-Build
-  git-buildpackage --git-pristine-tar
+It is possible (but extremely rare) that somebody uploads a MariaDB package to
+Debian/Ubuntu and either does not use git at all, or simply forgets to push the
+same changes on git, or makes an error in tagging the release or something.
+Therefore maintainers should check that the git contents match what has been
+uploaded to Debian/Ubuntu before making new changes on git.
 
-For a more elaborate setup with automatic build dependency installation and
-multi-target chroot usage check out how http://labs.seravo.fi/~otto/mariadb-repo/build.sh
-uses git-buildpackage with pbuilder.
+This can be done by using dgit. The example command below will fetch the latest
+mariadb-10.0 package available in Ubuntu 16.04 (Xenial) base archive or security
+archive (whichever has a newer version):
+  dgit -d ubuntu clone mariadb-10.0 xenial,-security
 
-If the build fails the easiest way to clean up before a new run is
-  git clean -fdx && git reset --hard
+You can then compare these two directories with a recursive diff.
 
+Another option is to manually check on packages.debian.org or packages.ubuntu.com
+what is the latest version, and download and extract it on top of the existing
+debian/ directory with:
+  curl -SL http://archive.ubuntu.com/ubuntu/pool/universe/m/mariadb-10.0/\
+  mariadb-10.0_10.0.34-0ubuntu0.16.04.1.debian.tar.xz -o - | tar xv --xz
 
-### Tip ###
+The you can simply run `git diff` to see the report on differences.
 
-  Don't run the mysql-test-run test suite as part of build.
-  It takes a lot of time, and we will do a better test anyway in
-  Buildbot, running the test suite from installed .debs on a clean VM.
 
-    export DEB_BUILD_OPTIONS="nocheck"
-
-  If you want to run the build in parallel on 2 CPUs and have verbose output, use:
-    export DEB_BUILD_OPTIONS="parallel=2 verbose"
-
-  The options above can also be combined freely to get required behaviour.
+## Building from sources with git-buildpackage ##
 
+See README.Contribute for details.
 
 ## Importing initial sources from upstream the first fime ##
 
@@ -49,7 +48,7 @@ Create repository
   cd mariadb-10.1
   git init
   git branch upstream
-  git-import-orig --pristine-tar ../../upstream/mariadb-10.1.20
+  gbp import-orig --pristine-tar ../../upstream/mariadb-10.1.20
 
 Fill in values prompted
   What will be the source package name? [mariadb] mariadb-10.1
@@ -81,44 +80,63 @@ https://mariadb.com/kb/en/mariadb/development/release-notes/
 
 Download new source package
   cd pkg-mariadb-10.1
-  uscan --verbose
+  gbp import-orig --uscan --no-interactive --verbose
 
-Enter git repository path and apply new sources
-  cd mariadb-10.1
-  git-import-orig --pristine-tar ../mariadb-10.1.20.tar.gz
+Refresh patches
+  while quilt push; do quilt refresh; done; quilt pop -a
+
+Simple offsets will be updated automatically. If there are any rejects, inspect
+the files and update the patches or discard the patch completely if you are
+_sure_ that it has been applied upstream.
 
 Generate new debian/changelog entry automatically with git-dch
   git-dch -avR
 
-Manually merge what needs to be done
+Edit the details to match correct release
+  gedit debian/changelog &
+
+Commit to git
+  git citool
+
+Build and test locally to verify it works.
+  gbp buildpackage --git-pristine-tar
+
+Alternatively you can use Docker with something like this:
+  mkdir ccache buildout
+  docker run -it -v "${PWD}/buildout":/tmp/build -v "${PWD}/ccache":/.ccache \
+     -v "${PWD}/$PKG":/tmp/build/source -w /tmp/build/source \
+     -e DEB_BUILD_OPTIONS="$DEB_BUILD_OPTIONS" -e CCACHE_DIR=/var/cache/ccache \
+     --user=1001 registry.gitlab.com/mariadb/mariadb.org-build-containers:$PKG-debian-sid-build-env \
+     gbp buildpackage --git-pristine-tar -us -uc | tee latest.build
 
-Commit and push
-  git commit -am "Merged with upstream 10.1.20"
-  git push --all; git push --all github
-  git push --tags; git push --tags github
+If needed, add commits or amend the ones you made until the package is in
+perfect shape.
 
-Note that in above if you want to sync to Github directly you need to have
-collaborator rights to the Github repo and you need to add it as a secondary
-remote location with:
-  git remote add origin git@github.com:ottok/mariadb-10.1.git
+Then proceed to make a source only build
+  gbp buildpackage -S
 
-To push to the git.debian.org repos you need to a member of the pkg-mysql team
-at Alioth. It does not matter which repository you push to, eventually they are
-synced with each other anyway.
+Test more with upload to Launchpad
+  COMMIT_ID=`git log -n 1 --oneline | cut -d ' ' -f 1`
+  PKG=mariadb-10.1
+  backportpackage --yes -u ppa:mysql-ubuntu/$PKG -d xenial -S ~`date '+%s'`.$COMMIT_ID $PKG*.dsc
 
+When done, push to Salsa:
+  git push -v
 
-### Maintaining patches ###
+Wait until the Salsa CI pipeline finishes. If it did not either spot any
+regressions, proceed to tagging the commit:
+  git tag -s ...
+  git push --tags
 
-Test that the patches still apply by running:
-  export QUILT_PATCHES=debian/patches
-  quilt import
-  quilt push -a
+Sign and upload to autobake for one final round of testing:
+  dput autobake *.changes
 
-If there are any rejects, inspect the files and update the patches.
+Once you are sure there are no regressions, finally upload to Debian
+  dput ftp-master *.changes
 
-If there are simple offsets we can refresh the patches simply with:
-  quilt pop -a
-  while quilt push; do quilt refresh; done
+After the upload, check that everything is OK at
+* https://tracker.debian.org/mariadb-10.1 (Debian)
+* https://launchpad.net/ubuntu/+source/mariadb-10.1 (Ubuntu)
 
 ### Maintaining debian/copyright ###
 
@@ -138,10 +156,10 @@ those cleaned up.
 ### Quality control ###
 
 Run wrap-and-sort to style contents in debian/*
-  wrap-and-sort
+  wrap-and-sort -a -t -v
 
 Once packages are done check their quality with Lintian
-  lintian -EvIL +pedantic --color=always *.deb
+  lintian -EvIL +pedantic --color=always *.changes
 
 
 ## Uploading to Ubuntu PPA for testing ##
@@ -154,8 +172,23 @@ These are good to have as environment variables (replace values with your own)
   DEBFULLNAME="Otto Kekäläinen"
   export DEBEMAIL DEBFULLNAME
 
-The run the commands to automatically change version and upload
-  backportpackage -u ppa:mysql-ubuntu/mariadb -d precise -r *.dsc -S ~ppa1 -y
+Then run the commands to automatically change version and upload
+  backportpackage --yes -u ppa:mysql-ubuntu/$PKG -d xenial -S ~`date '+%s'`.$COMMIT_ID $PKG*.dsc
+
+### Launchpad testing matrix
+
+Since Launchpad only has Ubuntu releases, packages for specific Debian releases
+needs to be tested on the Ubuntu release which most closely matches the Debian
+release in question. The following matrix maps what package should be tested
+where:
+
+- 10.3 for sid on launchpad cosmic
+- 10.1 for bionic on launchpad bionic
+- 10.0 for xenial on launchpad xenial
+- 10.1 for sid on launchpad cosmic
+- 10.1 for stretch on launchpad xenial
+- 10.0 for jessie on launhcpad trusty
+- 5.5. for trusy on launchpad trusty
 
 ## Uploading to Ubuntu security releases ##
 
@@ -170,6 +203,24 @@ that Ubuntu security team can apply upon the mix of previous debian/ contents
 from Ubuntu archive and updated others from upstream. This would allow to use
 git-buildpackage to produce test builds instead of plain 'fakeroot dpkg-buildpackage'.
 
+### Upload priority
+
+Do the security uploads in this order for having the best chance of catching
+regressions before they spread out to too many users.
+
+Upload priority for 10.1
+- debian sid
+- debian stretch
+- ubuntu bionic
+
+for 10.0
+- debian jessie
+- ubuntu xenial
+
+for 5.5
+- ubuntu trusty
+
+
 ## Comparison to other distributions ##
 
 For tracking security release information, finding solutions for build errors
@@ -193,4 +244,3 @@ are due to a bug in GCC which has been reported to GCC and will become fixed
 eventually:
   E array-bounds /??PKGBUILDDIR??/strings/decimal.c:300 (arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el, sparc)
   E array-bounds /??PKGBUILDDIR??/strings/decimal.c:496 (arm64, armel, armhf, i386, mips, mipsel, powerpc, ppc64el, sparc)
-