1 files changed, 73 insertions, 0 deletions
diff --git a/scripts/merge-train b/scripts/merge-train
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+#!/bin/sh
+
+set -e
+
+# The name (including namespace) of the EE repository to merge commits into.
+EE_PROJECT='gitlab-org/gitlab-ee'
+
+# The directory to clone GitLab EE into.
+EE_DIRECTORY="$CI_PROJECT_DIR/gitlab-ee"
+
+# The EE branch to merge the changes into.
+EE_BRANCH='master'
+
+# Runs an incremental or periodic merge of CE to EE. This script should be run
+# from a container built using https://gitlab.com/gitlab-org/merge-train.
+
+# Merges (or reverts) commits in a batch (based on CI_COMMIT_BEFORE_SHA and
+# CI_COMMIT_SHA), or since a specific commit.
+#
+# The optional first argument of this function should be a SHA of a commit. When
+# specified, all commits since this commit will be processed.
+merge() {
+    # We need to source the configure-ssh script instead of running it with
+    # `sh`, since it uses `eval` for SSH agent and we want the result of that to
+    # persist.
+    #
+    # shellcheck disable=SC1091
+    . /app/bin/configure-ssh
+
+    # We can not perform a shallow clone, as this results in Git sometimes
+    # refusing to fetch from CE. To work around this, we perform a full clone
+    # but cache the repository in CI. If a cached repository exists, we simply
+    # just pull from `master`.
+    if [ -d "$EE_DIRECTORY" ]
+    then
+        echo "Updating existing clone of $EE_PROJECT"
+
+        git -C "$EE_DIRECTORY" pull --quiet origin "$EE_BRANCH"
+    else
+        echo "Cloning $EE_PROJECT"
+
+        git clone --quiet --single-branch --branch "$EE_BRANCH" \
+            "git@gitlab.com:$EE_PROJECT.git" "$EE_DIRECTORY"
+    fi
+
+    cd /app
+
+    env GITLAB_TOKEN="$MERGE_TRAIN_API_TOKEN" \
+        bundle exec /app/bin/merge-train "$CI_PROJECT_DIR" "$EE_DIRECTORY" \
+        --source-name "$CI_PROJECT_PATH" \
+        --target-branch "$EE_BRANCH" \
+        ${1:+--before "$1"}
+}
+
+# Merges (or reverts) all commits since a point in time as supported by `git log
+# --since`, such as "12 hours ago".
+merge_since() {
+    commit="$(git log --since="$MERGE_SINCE" --reverse --format=%H | head -n1)"
+
+    if [ "$commit" = '' ]
+    then
+        echo "There are no commits to merge since $MERGE_SINCE"
+    else
+        merge "$commit"
+    fi
+}
+
+if [ "$MERGE_SINCE" ]
+then
+    merge_since
+else
+    merge
+fi