ci: Automate changelog generation

.github/workflows/release-entry.yaml

@@ -0,0 +1,53 @@
+name: Release Changelog
+
+on:
+  push:
+    # Automatically create a GitHub Release entry when a tag that looks like a new release is pushed.
+    # The tag pattern is defined in maven-release-plugin's settings in pom.xml authoritatively. The changelog
+    # generator - git-cliff - just goes through all relevant tags, regardless of their name.
+    tags:
+      - 'v[0-9]+.*'
+
+jobs:
+  release:
+    name: Create GitHub Release entry
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed by softprops/action-gh-release to create the GitHub Release entry:
+      contents: write
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          persist-credentials: false
+
+      - uses: cachix/install-nix-action@v31
+
+      - uses: cachix/cachix-action@v16
+        with:
+          name: devenv
+
+      - name: Install devenv.sh
+        run: nix profile install nixpkgs#devenv
+
+      - name: Generate change list
+        shell: devenv shell bash -- -e {0}
+        run: |
+          task release:changelog FILE=changes.md
+
+      - name: Include the change list in summary
+        shell: devenv shell bash -- -e {0}
+        continue-on-error: true
+        run: |
+          echo -e "# Generated change list:\n\n----\n\n" >> "$GITHUB_STEP_SUMMARY"
+          cat changes.md >> "$GITHUB_STEP_SUMMARY"
+
+      - name: Create GitHub Release entry
+        uses: softprops/action-gh-release@v2
+        if: github.ref_type == 'tag'
+        with:
+          # Populate the release entry body with the notes we generated
+          body_path: changes.md
+          # A hooman still needs to push the butan
+          draft: true
+
+# eof

Taskfile.yaml

@@ -22,15 +22,21 @@ tasks:
     cmds:
       - cmd: mvn -Pupgrades
 
-  maintenance:check-reproducibility:
+  release:changelog:
+    desc: Creates list of changes since the last release tag
+    cmds:
+      - cmd: git-cliff --current --unreleased --output {{ .FILE | default "-" | shellQuote }}
+
+  release:check-reproducibility:
     # See https://maven.apache.org/guides/mini/guide-reproducible-builds.html
     desc: Check if artifacts are reproducible
     cmds:
       - cmd: mvn artifact:check-buildplan
       - cmd: mvn clean install
       - cmd: mvn clean verify artifact:compare
+      - cmd: mvn clean
 
-  maintenance:release:
+  release:create:
     desc: Cuts off a new release and deploys artifacts to Sonatype Maven Central
     summary: |
       This task verifies that appropriate credentials have been entered, cuts off a new
@@ -81,6 +87,7 @@ tasks:
           echo
 
       - cmd: echo "This step primes GnuPG cache so it can be used in non-interactive mode" | gpg --clearsign
+      - task: release:check-reproducibility
       - cmd: mvn --settings={{ .SETTINGS_FILE | shellQuote }} -Prelease -DdryRun=true
       - cmd: mvn --settings={{ .SETTINGS_FILE | shellQuote }} -Prelease
       - silent: true

cliff.toml

@@ -0,0 +1,92 @@
+# git-cliff ~ configuration file
+# https://github.com/orhun/git-cliff
+# https://git-cliff.org/docs/configuration
+
+[changelog]
+# A Tera template to be rendered for each release in the changelog.
+# See https://keats.github.io/tera/docs/#introduction
+body = """
+{% if version %}\
+    ## [{{ version }}] - {{ timestamp | date(format="%Y-%m-%d") }}
+{% else %}\
+    ## [unreleased]
+{% endif %}\
+{% for group, commits in commits | group_by(attribute="group") %}
+    ### {{ group | striptags | trim | upper_first }}
+    {% for commit in commits %}
+        * {% if commit.scope %}*({{ commit.scope }})* {% endif %}\
+            {% if commit.breaking %}[**breaking**] {% endif %}\
+            {{ commit.message | upper_first | split(pat='\n') | first }}\
+    {% endfor %}
+{% endfor %}
+"""
+# Remove leading and trailing whitespaces from the changelog's body.
+trim = true
+# Render body even when there are no releases to process.
+render_always = true
+# An array of regex based postprocessors to modify the changelog.
+postprocessors = [
+  # Replace the placeholder <REPO> with a URL.
+  { pattern = '<REPO>', replace = "https://github.com/tguzik/valueclasses" },
+]
+# Default output file path
+#output = "CHANGELOG.md"
+
+[git]
+# Parse commits according to the conventional commits specification.
+# See https://www.conventionalcommits.org
+conventional_commits = true
+# Exclude commits that do not match the conventional commits specification.
+filter_unconventional = false
+# Require all commits to be conventional.
+# Takes precedence over filter_unconventional.
+require_conventional = false
+# Split commits on newlines, treating each line as an individual commit.
+split_commits = false
+# An array of regex based parsers to modify commit messages prior to further processing.
+commit_preprocessors = [
+  # Replace issue numbers with link templates to be updated in `changelog.postprocessors`.
+  { pattern = '\((\w+\s)?#([0-9]+)\)', replace = "([#${2}](<REPO>/issues/${2}))" },
+]
+# Prevent commits that are breaking from being excluded by commit parsers.
+protect_breaking_commits = true
+# An array of regex-based parsers that assign commits to a group.
+# Optionally sets the commit's scope and can decide to exclude commits from further processing.
+# The regex is applied over the whole message.
+
+# The entries here are processed in order and the first matched regex (the `message` prop) will assign the commit to a group. The
+# groups in the output appear in the ascending lexical order of the group names, not the order of these entries. The HTML comment
+# in the name of the group still participates in sorting but is omitted from the output - we're using it to manually set the
+# order.
+# Additional examples: https://git-cliff.org/docs/configuration/git#commit_parsers
+commit_parsers = [
+  { message = "^feat", group = "<!-- 01 -->Features:" },
+  { message = "^fix", group = "<!-- 02 -->Bug Fixes:" },
+  { message = "^doc", group = "<!-- 03 -->Documentation:" },
+  { message = "^perf", group = "<!-- 04 -->Performance:" },
+  { message = "^refactor", group = "<!-- 05 -->Refactor:" },
+  { message = "^style", group = "<!-- 06 -->Code Styling:" },
+  { message = "^test", group = "<!-- 07 -->Testing:" },
+  { message = "^deps|^build\\(deps(-dev)?\\)", group = "<!-- 08 -->Dependencies:" },
+  { message = "^build|^ci|^chore", group = "<!-- 09 -->Maintenance:" },
+  { message = "^revert", group = "<!-- 10 -->Revert:" },
+  # { message = "^chore\\(pull\\)", skip = true },
+  { message = ".*", group = "<!-- 11 -->Other:" },
+]
+# Exclude commits that are not matched by any commit parser.
+filter_commits = false
+# An array of link parsers for extracting external references, and turning them into URLs, using regex.
+link_parsers = []
+# Include only the tags that belong to the current branch.
+use_branch_tags = false
+# Order releases topologically instead of chronologically.
+topo_order = false
+# Order releases topologically instead of chronologically.
+topo_order_commits = true
+# Order of commits in each group/release within the changelog.
+# Allowed values: newest, oldest
+sort_commits = "newest"
+# Process submodules commits
+recurse_submodules = false
+
+# eof

devenv.nix

@@ -14,12 +14,21 @@
   # https://devenv.sh/packages/
   # https://search.nixos.org/packages
   # Note that the JDK and Maven are already pulled in through the `languages.java` props.
-  packages = [
+  packages = with pkgs; [
     # Basic utilities
-    pkgs.curl
-    pkgs.git
-    pkgs.go-task
-    pkgs.gnupg
+    curl
+    git
+    go-task
+    gnupg
+
+    # Maven Daemon
+    # https://github.com/apache/maven-mvnd
+    mvnd
+
+    # Highly customizable changelog generator
+    # https://github.com/orhun/git-cliff
+    # https://git-cliff.org/docs/
+    git-cliff
   ];
 
   git-hooks.hooks = {