add scripts/get_module_version.sh

This script consumes a Prometheus version (or version tag) and prints
the appropriate module version.

Signed-off-by: Jan Fajerski <jfajersk@redhat.com>

.github/workflows/ci.yml

@@ -253,7 +253,7 @@ jobs:
           (github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v2.'))
           ||
           (github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v3.'))
-        run: ./scripts/ui_release.sh --check-package "$(echo ${{ github.ref_name }}|sed s/v2/v0/)"
+        run: ./scripts/ui_release.sh --check-package "$(./scripts/get_module_version.sh ${{ github.ref_name }})"
       - name: build
         run: make assets
       - name: Copy files before publishing libs

RELEASE.md

@@ -187,7 +187,7 @@ the Prometheus server, we use major version zero releases for the libraries.
 Tag the new library release via the following commands:
 
 ```bash
-tag="v$(sed s/2/0/ < VERSION)"
+tag="v$(./scripts/get_module_version.sh)"
 git tag -s "${tag}" -m "${tag}"
 git push origin "${tag}"
 ```

scripts/get_module_version.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+# if no version string is passed as an argument, read VERSION file
+if [ $# -eq 0 ]; then
+    VERSION="$(< VERSION)"
+else
+    VERSION=$1
+fi
+
+
+# Remove leading 'v' if present
+VERSION="${VERSION#v}"
+
+# Extract MAJOR, MINOR, and REST
+MAJOR="${VERSION%%.*}"
+MINOR="${VERSION#*.}"; MINOR="${MINOR%%.*}"
+REST="${VERSION#*.*.}"
+
+# Format and output based on MAJOR version
+if [[ "$MAJOR" == "2" ]]; then
+    echo "0.$MINOR.$REST"
+elif [[ "$MAJOR" == "3" ]]; then
+    printf "0.3%02d.$REST\n" "$MINOR"
+fi