feat(ci): Automatically generate changelog from commit messages

Commit messages since the previous release have been rewritten to
match the current changelog generator template

.github/chglog/CHANGELOG.tpl.md

@@ -0,0 +1,32 @@
+{{ range .Versions }}
+<a name="{{ .Tag.Name }}"></a>
+## {{ if .Tag.Previous }}[{{ .Tag.Name }}]({{ $.Info.RepositoryURL }}/compare/{{ .Tag.Previous.Name }}...{{ .Tag.Name }}){{ else }}{{ .Tag.Name }}{{ end }}
+
+> {{ datetime "2006-01-02" .Tag.Date }}
+
+{{ range .CommitGroups -}}
+### {{ .Title }}
+
+{{ range .Commits -}}
+* {{ if .Scope }}**{{ .Scope }}:** {{ end }}{{ .Subject }}
+{{ end }}
+{{ end -}}
+
+{{- if .RevertCommits -}}
+### Reverts
+
+{{ range .RevertCommits -}}
+* {{ .Revert.Header }}
+{{ end }}
+{{ end -}}
+
+{{- if .NoteGroups -}}
+{{ range .NoteGroups -}}
+### {{ .Title }}
+
+{{ range .Notes }}
+{{ .Body }}
+{{ end }}
+{{ end -}}
+{{ end -}}
+{{ end -}}

.github/chglog/config.yml

@@ -0,0 +1,28 @@
+style: github
+template: CHANGELOG.tpl.md
+info:
+  title: CHANGELOG
+  repository_url: https://github.com/wdullaer/scotty
+options:
+  commits:
+    filters:
+      Type:
+        - feat
+        - fix
+        - docs
+        - refactor
+  commit_groups:
+    title_maps:
+      feat: Features
+      fix: Bug Fixes
+      refactor: Code Refactoring
+      docs: Documentation
+  header:
+    pattern: "^(\\w*)(?:\\(([\\w\\$\\.\\-\\*\\s]*)\\))?\\:\\s(.*)$"
+    pattern_maps:
+      - Type
+      - Scope
+      - Subject
+  notes:
+    keywords:
+      - BREAKING CHANGE

.github/workflows/workflow.yml

@@ -206,6 +206,16 @@ jobs:
       - name: Generate checksums
         run: for file in scotty-*; do openssl dgst -sha256 -r "$file" | awk '{print $1}' > "${file}.sha256"; done
 
+      - name: Install go (needed for changelog tool)
+        uses: actions/setup-go@v1
+        with:
+          go-version: 1.13
+      - name: Generate changelog
+        run: |
+          export PATH=${PATH}:$(go env GOPATH)/bin
+          go get -u github.com/git-chglog/git-chglog/cmd/git-chglog
+          git-chglog -c .github/chglog/config.yml $(git describe --tags) > CHANGELOG.md
+
       - name: Create GitHub release ${{ matrix.target }}
         uses: softprops/action-gh-release@v1
         with:
@@ -218,5 +228,6 @@ jobs:
             scotty-x86_64-apple-darwin.tar.gz.sha256
             scotty-x86_64-pc-windows-msvc.zip
             scotty-x86_64-pc-windows-msvc.zip.sha256
+          body_path: CHANGELOG.md
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}