From 47a9913de47d0dbf9c46404a11d024133d79c90d Mon Sep 17 00:00:00 2001
From: David Michael <david.michael@coreos.com>
Date: Tue, 18 Apr 2017 13:55:27 -0700
Subject: [PATCH] tag_release: branch important projects automatically for
 alpha tags

Now when an alpha is tagged (i.e. it branches off master.xml), the
manifest repository still gets a tag, a commit on master, and a new
build branch pointing at that commit, but by default an additional
commit is appended to the build branch that branches the projects
coreos-overlay, portage-stable, and scripts in the manifest.  When
given the --push option, a build branch is created in each of these
project repositories so everything is prepared for future minor
releases to build upon.

This is implemented in yet another option so that the previous
behavior is still available, but it probably makes sense to just
hard-code the default behavior of --branch and --branch_projects
and drop those options.
---
 tag_release | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/tag_release b/tag_release
index 1d7e380caa..ce2afba012 100755
--- a/tag_release
+++ b/tag_release
@@ -10,6 +10,7 @@ SCRIPT_ROOT=$(dirname $(readlink -f "$0"))
 DEFAULT_MAJOR=${TODAYS_VERSION}
 DEFAULT_MINOR=0
 DEFAULT_BRANCH=${FLAGS_FALSE}
+DEFAULT_BRANCH_PROJECTS=
 
 CURRENT_VERSION=( ${COREOS_VERSION_ID//./ } )
 
@@ -19,6 +20,8 @@ DEFAULT_MANIFEST=$(readlink "${REPO_MANIFESTS_DIR}/default.xml") \
 if [[ "${DEFAULT_MANIFEST}" != master.xml ]]; then
     DEFAULT_MAJOR=${CURRENT_VERSION[0]}
     DEFAULT_BRANCH=${FLAGS_TRUE}
+else
+    DEFAULT_BRANCH_PROJECTS='coreos-overlay portage-stable scripts'
 fi
 
 # Increment $MINOR if we already made a major release.
@@ -32,6 +35,8 @@ DEFINE_integer patch 0 "Branch patch id, normally 0"
 DEFINE_string sdk_version "${COREOS_VERSION_ID}" \
     "SDK version to use, or 'keep'. (current: ${COREOS_SDK_VERSION})"
 DEFINE_boolean branch ${DEFAULT_BRANCH} "Release branch, diverge from master"
+DEFINE_string branch_projects "${DEFAULT_BRANCH_PROJECTS}" \
+    "Branch the named projects (with a 'coreos/' prefix) in the manifest."
 DEFINE_boolean push ${FLAGS_FALSE} "Push to public manifest repository."
 DEFINE_string remote "origin" "Remote name or URL to push to."
 DEFINE_string signer '' "Alternate GPG key ID used to sign the tag."
@@ -123,12 +128,33 @@ git commit -m "${BRANCH_NAME}: release ${TAG_NAME}"
 git branch -f "${BRANCH_NAME}"
 git tag "${sign_args[@]}" -m "CoreOS ${TAG_NAME}" "${TAG_NAME}"
 
+# Unpin and branch the important projects, if requested and they are pinned.
+if [[ -n "${FLAGS_branch_projects}" ]]; then
+    sed -i -e "/ name=\"coreos\/\(${FLAGS_branch_projects// /\\|}\)\" /s%revision=.*upstream=.*\"%revision=\"refs/heads/${BRANCH_NAME}\"%" "${BRANCH_NAME}.xml"
+    ln -sf "${BRANCH_NAME}.xml" default.xml
+    git add default.xml "${BRANCH_NAME}.xml"
+    git commit -m "${BRANCH_NAME}: branch projects" -m "Branched: ${FLAGS_branch_projects}"
+    git branch -f "${BRANCH_NAME}"
+    git reset --hard HEAD^
+
+    # Create new branches in the projects' upstream repositories.
+    if [[ ${FLAGS_push} -eq ${FLAGS_TRUE} ]]; then
+        remote=$(sed -n '/<default /s/.* remote="\([^"]*\)".*/\1/p' release.xml)
+        for project in ${FLAGS_branch_projects}; do
+            info=$(sed -n 's,.* name="coreos/'${project}'".* path="\([^"]*\)".* revision="\([0-9A-Fa-f]*\)".*,\2 \1,p' release.xml)
+            info "Creating branch ${BRANCH_NAME} at ${info%% *} in ${project}"
+            git -C "${REPO_ROOT}/${info#* }" push "${remote}" "${info%% *}:refs/heads/${BRANCH_NAME}"
+        done
+    fi
+fi
+
 if [[ ${FLAGS_push} -eq ${FLAGS_TRUE} ]]; then
     master="HEAD:refs/heads/master"
     if [[ ${FLAGS_branch} -eq ${FLAGS_TRUE} ]]; then
         master=""
     fi
 
+    info 'Pushing manifest updates'
     git push "${FLAGS_remote}" $master \
         "refs/heads/${BRANCH_NAME}" \
         "refs/tags/${TAG_NAME}"