add script for maintainer to build CHANGELOG entries

Author: ezhang6811

CHANGELOG.md

@@ -3,9 +3,3 @@
 All notable changes to this project will be documented in this file.
 
 > **Note:** This CHANGELOG was created starting from version 0.12.0. Earlier changes are not documented here.
-
-## Unreleased
-
-## 0.11.0 - 2024-08-20
-
-- Initial CHANGELOG implementation ([#465](https://github.com/aws-observability/aws-otel-python-instrumentation/pull/465))

scripts/draft-changelog.sh

@@ -0,0 +1,28 @@
+#!/bin/bash -e
+
+# Find the latest release tag that's in the current branch's history
+latest_tag=""
+for tag in $(git tag -l "v*.*.*" --sort=-version:refname); do
+  if git merge-base --is-ancestor "$tag" HEAD; then
+    latest_tag="$tag"
+    break
+  fi
+done
+
+if [[ -z $latest_tag ]]; then
+  echo "No release tags found in current branch history"
+  exit 1
+fi
+
+echo "# Changes since $latest_tag:"
+echo
+
+# Generate changelog entries from commits since the tag
+git log --reverse \
+        --perl-regexp \
+        --author='^(?!dependabot\[bot\] )(?!github-actions\[bot\] )' \
+        --pretty=format:"- %s" \
+        "$latest_tag..HEAD" \
+  | grep -E '\(#[0-9]+\)$' \
+  | grep -v '^- Post release ' \
+  | sed -E 's,\(#([0-9]+)\)$, ([#\1](https://github.com/aws-observability/aws-otel-python-instrumentation/pull/\1)),'