feat: add a "match_tags" option

I use this action to release the chart of [Mercure](https://mercure.rocks).
We use a monolithic Git repository containing several projects, including the Helm chart.
Currently, this action isn't compatible with our setup because it computes the changes
made to the chart since the previous tag.

In our case we also use tags for other projects in the same repository,
so this actions is never triggered because there are no changes with the "previous" tag (which usually is for another project in the same repository).

This PR introduces a `match_tags` option allowing to filter the tags to match using a glob.

Signed-off-by: Kévin Dunglas <dunglas@gmail.com>
Signed-off-by: Kévin Dunglas <kevin@dunglas.fr>

README.md

@@ -20,6 +20,7 @@ A GitHub action to turn a GitHub project into a self-hosted Helm chart repo, usi
 - `charts_dir`: The charts directory
 - `skip_packaging`: This option, when populated, will skip the packaging step. This allows you to do more advanced packaging of your charts (for example, with the `helm package` command) before this action runs. This action will only handle the indexing and publishing steps.
 - `mark_as_latest`: When you set this to `false`, it will mark the created GitHub release not as 'latest'.
+- `match_tags`: The glob to use to filter Git tags, usually used with the `CR_RELEASE_NAME_TEMPLATE` environment variable (default: all tags)
 
 ### Outputs
 

action.yml

@@ -32,6 +32,9 @@ inputs:
     description: Mark the created GitHub release as 'latest'
     required: false
     default: true
+  match_tags:
+    description: "The glob to use to filter Git tags (default: all tags)"
+    required: false
 outputs:
   changed_charts:
     description: "A comma-separated list of charts that were released on this run. Will be an empty string if no updates were detected, will be unset if `--skip_packaging` is used: in the latter case your custom packaging step is responsible for setting its own outputs if you need them."
@@ -84,6 +87,10 @@ runs:
             args+=(--mark-as-latest "${{ inputs.mark_as_latest }}")
         fi
 
+        if [[ -n "${{ inputs.match_tags }}" ]]; then
+            args+=(--match-tags "${{ inputs.match_tags }}")
+        fi
+
         "$GITHUB_ACTION_PATH/cr.sh" "${args[@]}"
 
         if [[ -f changed_charts.txt ]]; then

cr.sh

@@ -35,6 +35,7 @@ Usage: $(basename "$0") <options>
     -s, --skip-packaging     Skip the packaging step (run your own packaging before using the releaser)
         --skip-existing      Skip package upload if release exists
     -l, --mark-as-latest     Mark the created GitHub release as 'latest' (default: true)
+    -m, --match-tags         The glob to use to filter Git tags (default: all tags)
 EOF
 }
 
@@ -44,6 +45,7 @@ main() {
   local charts_dir=charts
   local owner=
   local repo=
+  local match_tags=
   local install_dir=
   local install_only=
   local skip_packaging=
@@ -164,6 +166,16 @@ parse_command_line() {
         exit 1
       fi
       ;;
+    -m|--match-tags)
+      if [[ -n "${2:-}" ]]; then
+        match_tags="$2"
+        shift
+      else
+        echo "ERROR: '--match-tags' cannot be empty." >&2
+        show_help
+        exit 1
+      fi
+      ;;
     -n | --install-dir)
       if [[ -n "${2:-}" ]]; then
         install_dir="$2"
@@ -249,7 +261,13 @@ install_chart_releaser() {
 lookup_latest_tag() {
   git fetch --tags >/dev/null 2>&1
 
-  if ! git describe --tags --abbrev=0 HEAD~ 2>/dev/null; then
+  args=("describe" "--tags" "--abbrev=0")
+  if [ -n "$match_tags" ]; then
+    args+=(--match="$match_tags")
+  fi
+  args+=(HEAD~)
+
+  if ! git "${args[@]}" 2> /dev/null; then
     git rev-list --max-parents=0 --first-parent HEAD
   fi
 }