snap/scripts/version: Update for usage in monorepo (#1295)

Author: adombeck

snap/scripts/version

@@ -4,55 +4,33 @@ set -eu
 # This scripts prints the version of the snap based on the git tags and the
 # current branch. The version is determined as follows:
 #
-# If there's a tag prefixed with the current branch name, that tag is
-# used and the prefix is stripped. For example:
-# * msentraid-0.1.0 -> 0.1.0
+# The highest version tag which is prefixed with "broker-" and is merged into the
+# current branch is used as the base version.
+# If there is no such tag, "0.0.0" is used as the base version.
 #
-# Else, the highest version tag that starts with a number (in contrast
-# to a prefix like "msentraid-") is used. For example:
-# * 0.1.0 -> 0.1.0
+# If the current commit is tagged, that tag is used as the version as is.
 #
-# 1. If current commit is tagged, that tag is used as the version as is.
-# 2. If current commit is not tagged, the version is:
-#    * When on main: <latest tag on current branch>+<commit_sha>
-#    * Else: <latest tag on current branch>+<commit_sha>.<last_commit_merged_from_main>
+# If the current commit is not tagged, the version is appended with the short
+# sha of the current commit. When the current branch is not "main", the version
+# is further appended with the short sha of the last commit merged from the main
+# branch.
 #
-# The version is appended with ".dirty" if there are uncommitted changes.
-
-# strip_branch_tag_prefix removes any non-numeric prefix ending with a
-# dash (e.g. "msentraid-") from the tag name. We use this to remove the
-# branch name prefix from the tag name, but we do not just strip the
-# current branch name because we also want to support branching of a new
-# branch and use the latest tag from that branch (for example when
-# branching of the msentraid branch to test a fix, then that branch
-# should still use a valid version).
-# $1: tag: the tag name to strip the prefix from.
-strip_branch_tag_prefix() {
-    tag="${1}"
-
-    echo "${tag}" | sed 's/^[^0-9-]*-//'
-}
+# Finally, the version is appended with ".dirty" if there are uncommitted changes.
 
 get_version() {
     current_branch=$(git branch --show-current)
 
-    # Get the highest version tag which is prefixed with the current branch name.
-    tag=$(git -c "versionsort.suffix=-pre" tag --sort=-v:refname --merged="${current_branch}" | grep "^${current_branch}-" | head -1)
+    # Get the highest version tag which is prefixed with "broker-"
+    tag=$(git -c "versionsort.suffix=-pre" tag --sort=-v:refname --merged="${current_branch}" | grep -E '^broker-' | head -n 1)
+    version="${tag}"
 
-    # If there is no tag prefixed with the current branch name, use the most
-    # recent tag that does not have a non-numerical prefix (that's the case
-    # when we're building a snap for testing on a branch that's not
-    # "msentraid" or "google").
-    if [ -z "${tag}" ]; then
-        tag=$(git -c "versionsort.suffix=-pre" tag --sort=-v:refname --merged="${current_branch}" | grep -E '^[0-9]+' | head -1)
-    fi
+    # Strip the "broker-" prefix
+    version="${version#broker-}"
 
-    version="${tag}"
     if [ -z "${version}" ]; then
-        # No tag found, use "notag" as version.
-        version="notag"
+        # No tag found, use "0.0.0"
+        version="0.0.0"
     fi
-    version=$(strip_branch_tag_prefix "${version}")
 
     # If the highest version tag is on the current commit, use it as is after
     # stripping the prefix.
@@ -64,15 +42,15 @@ get_version() {
     # Current commit is not tagged, append commit(s) sha.
     version="${version}+$(git rev-parse --short=7 HEAD)"
 
-    # Main branch will be set as is.
+    # If the current branch is not "main", append the short sha of the last commit
     if [ "${current_branch}" = "main" ]; then
+        # Current branch is "main", return the version as is.
         echo "${version}"
         return
     fi
 
-    # Get the short version of last commit merged from the main branch.
-    last_commit_on_main=$(git merge-base main HEAD)
-    last_commit_on_main=$(git rev-parse --short=7 "${last_commit_on_main}")
+    # Get the short version of the last commit merged from the main branch.
+    last_commit_on_main=$(git rev-parse --short=7 "$(git merge-base main HEAD)")
     echo "${version}.${last_commit_on_main}"
 }