Ceph » Stable releases

Before a backported commit can be merged into the release branch, it must be tested in an integration branch. It serves two purposes:

* Detect trivial problems that would break the upgrade tests run on the release branch (they are run at the tip of the branch, not at the latest point release)

* Do not pollute the release branch with reverted commits (commits would have to be reverted because the stable branch must never be rebased)

Let say the release to be tested is *$release* (i.e. giant for instance) and your local clone has two remotes: *origin* which is your read/write fork of the official ceph repository and *ceph* which is the read only official ceph repository.

<pre>

ceph	https://github.com/ceph/ceph.git (fetch)

ceph	https://github.com/ceph/ceph.git (push)

origin	git@github.com:dachary/ceph.git (fetch)

origin	git@github.com:dachary/ceph.git (push)

</pre>

* Create a $release-backports branch locally if it does not already exists: *git checkout -b $release-backports ceph/$release*

* Reset it to ceph/$release: *git reset --hard ceph/$release*

* Fetch all pull requests from github. Each pull request XXX has its own branch in the official ceph repository, named *pull/XXX*

** For finding out the pull requests in github against a milestone; Github's api can be queried. Since github paginates results by default, this has to be run against all the pages. 

<pre>

pages=$(curl -Is 'https://api.github.com/repos/ceph/ceph/issues?page=1&per_page=100' | grep ^Link | sed  's/.*?page=\([0-9]\+\).*/\1/')

PRS=""

for i in $(seq 1 $pages)

do

    PRS+=$(curl --silent 'https://api.github.com/repos/ceph/ceph/issues?page=$page&per_page=100' | jq --arg release "$release" '.[] | select(.milestone.title == $release) | .number')

    PRS+=' ' # otherwise we'll have a PR number that is appending the last PR from this loop

done

</pre>

** Retrieve the commits of the pull request XXX: *git fetch --force ceph +refs/pull/XXX/head:refs/remotes/ceph/pull/XXX/head*

** Get the title of the pull request: *eval title=$(curl --silent https://api.github.com/repos/ceph/ceph/pulls/XXX | jq .title)*

** Merge the pull request in the local integration branch. The *--no-ff* ensures that even if the merge commit could be skipped, it will not be. *git merge --no-ff -m "$(echo -e "Merge XXX: $title\n\nReviewed-by: Myself <me@me.com>")" ceph/pull/XXX/head*

* Modify the pull requests individually to fix merge conflicts (i.e. they must merge cleanly, which may involving aggregating two pull requests into a single one designed to properly resolve the conflict). 

* Push the integration branch to github: *git push --force origin $release-backports*

* Verify the integration branch compiles and passes make check

** On the local machine: *./run-make-check.sh*

** Via the make check bot by creating a pull request with the $release-backports* integration branch

* Push the integration branch to the official repository: *git push --force ceph $release-backports* (requires write permission to the ceph repository)

The following snippet summarizes all the actions above:

<pre>

github_token=55844b338f33e616d6fec2ee # dachary

release=hammer

reviewer='Loic Dachary <ldachary@redhat.com>'

function collect_prs() {

    local pages=$(curl -Is "https://api.github.com/repos/ceph/ceph/issues?page=1&per_page=100&access_token=$github_token" | grep ^Link | sed  's/.*?page=\([0-9]\+\).*/\1/')

    local page

    for page in $(seq 1 $pages)

    do

        curl --silent "https://api.github.com/repos/ceph/ceph/issues?page=$page&per_page=100&access_token=$github_token" | jq --arg release "$release" '.[] | select(.milestone.title == $release) | select(.title | contains("DNM") | not) | [.number, .title] | @sh' | while read line ; do 

            eval eval set $line

            echo $1

            echo "https://github.com/ceph/ceph/pull/$1 $2" >&2

        done

    done

}

PRS=$(collect_prs)

git checkout -b $release-backports ceph/$release

git reset --hard ceph/$release

git fetch --force ceph $(for ref in $PRS ; do echo +refs/pull/$ref/head:refs/remotes/ceph/pull/$ref/head ; echo +refs/pull/$ref/merge:refs/remotes/ceph/pull/$ref/merge ; done)

for pr in $PRS ; do eval title=$(curl --silent https://api.github.com/repos/ceph/ceph/pulls/$pr?access_token=$github_token | jq .title) ; echo "$pr $title" ; git --no-pager log --oneline ceph/pull/$pr/merge^1..ceph/pull/$pr/merge^2 ; git --no-pager merge --no-ff -m "$(echo -e "Merge $pr: $title\n\nReviewed-by: $reviewer")" ceph/pull/$pr/head ; done

git push --force ceph $release-backports

# hack to figure out what conflicts with what, lot of room for improvement

# PRS_B are the PRS found to conflict and set aside

PRS_A="5171 5170 5129 5062 5056 5051 5044 5043 5039 5037 4867 4788 4771 4769 4765 4762 4642 4641 4639 4633 4632 4631 4630 4584 4583 4582 4535" PR_B="4635 4636 4597"

for pr_a in $PR_A ; do git reset --hard ceph/$release ; for pr_b in $PR_B ; do git --no-pager merge --no-ff -m "$(echo -e "Merge $pr_a" ceph/pull/$pr/head ; git --no-pager merge --no-ff -m "Merge $pr_b" ceph/pull/$pr/head || echo "CONFLICT $pr_a $pr_b" ; done ; done

</pre>