From e6a9a0e3cdd02d55ac98d4e909fc27d6031a1075 Mon Sep 17 00:00:00 2001
From: Jonathan Wren <jonathan@nowandwren.com>
Date: Tue, 14 Jan 2020 20:06:14 -0800
Subject: [PATCH] add script to generate changelog

---
 .build/generate_changelog.sh | 40 ++++++++++++++++++++++++++++++++++++
 .travis.yml                  |  8 ++++++++
 2 files changed, 48 insertions(+)
 create mode 100755 .build/generate_changelog.sh

diff --git a/.build/generate_changelog.sh b/.build/generate_changelog.sh
new file mode 100755
index 00000000..b0267422
--- /dev/null
+++ b/.build/generate_changelog.sh
@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+
+FILENAME='CHANGELOG.md'
+
+# get the latest git tags
+gittags="$(git tag --sort=-creatordate | grep -Ev '(alpha|beta|rc)')"
+gittag_latest=$(printf '%s' "$gittags" | awk 'NR==1')
+gittag_secondlatest=$(printf '%s' "$gittags" | awk 'NR==2')
+
+echo "gittag_latest: ${gittag_latest}"
+echo "gittag_secondlatest: ${gittag_secondlatest}"
+
+# delete generated line (or it will be added multiple times)
+sed -i '/This Changelog was automatically generated by/d' "$FILENAME"
+
+# delete trailing empty lines
+sed -i -e :a -e '/^\n*$/{$d;N;};/\n$/ba' "$FILENAME"
+
+# determine correct tag to go back to
+# @TODO
+if [[ ! -z $TRAVIS_TAG ]]; then
+  echo "release build"
+  gittag=${gittag_secondlatest}
+else
+  echo "merge into master or develop"
+  gittag=${gittag_latest}
+fi
+echo "gittag: ${gittag}"
+
+# find the line the tag starts on, and subtract 1
+tagline=$(grep -n "^## \[\?$gittag\]\?" CHANGELOG.md | awk '{print $1}' FS=':' | head -1)
+echo "tagline: ${tagline}"
+[[ ! -z $tagline ]] && sed -i "1,$(expr $tagline - 1)d" "$FILENAME"
+
+# generate the changelog
+docker run -it --rm -v "$(pwd)":/usr/local/src/your-app ferrarimarco/github-changelog-generator -t $CHANGELOG_GITHUB_TOKEN --since-tag $gittag
+
+# @TODO commit changes, etc
+git diff
+
diff --git a/.travis.yml b/.travis.yml
index 079442b0..0f6757cf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -114,6 +114,14 @@ jobs:
       env:
         - TZ=America/Edmonton
 
+    # Changelog for Unreleased changes
+    - stage: Update Changelog
+      if: (tag IS present) OR (branch = develop AND type NOT IN (pull_request))
+      install:
+        - echo 'Skipping install'
+      script:
+        - ./.build/generate_changelog.sh
+
     - stage: Deploy
       before_deploy:
         - poetry config pypi-token.pypi "$PYPI_TOKEN"