Add draft-release.py script (#968)

RELEASE.md

@@ -13,7 +13,10 @@
       - If necessary, add a note detailing any impact to externally facing APIs.
    1. Update `packages/jaeger-ui/package.json#version` to refer to the version being released.
 1. Create a GitHub release.
-   - The tag and release must refer to the commit created when the PR from the previous step was merged.
-   - The tag name for the GitHub release should be the version for the release. It should include the "v", e.g. `v1.0.0`.
-   - The title of the release match the format "Jaeger UI vX.Y.Z".
-   - Copy the new CHANGELOG.md section into the release notes.
+   - Automated (requires [gh](https://cli.github.com/manual/installation)):
+     - `python ./scripts/draft-release.py`
+   - Manual:
+     - The tag and release must refer to the commit created when the PR from the previous step was merged.
+     - The tag name for the GitHub release should be the version for the release. It should include the "v", e.g. `v1.0.0`.
+     - The title of the release match the format "Jaeger UI vX.Y.Z".
+     - Copy the new CHANGELOG.md section into the release notes.

scripts/draft-release.py

@@ -0,0 +1,47 @@
+import re
+import subprocess
+
+
+release_header_pattern = re.compile(r"## (v[\d]+\.[\d]+\.[\d]) \([\d]{4}-[\d]{2}-[\d]{2}\)", flags=0)
+
+
+def main():
+    changelog_text, version = get_changelog()
+    print(changelog_text)
+    output_string = subprocess.check_output(
+        ["gh", "release", "create", version,
+         "--draft",
+         "--title", f"Jaeger UI {version}",
+         "--repo", "jaegertracing/jaeger-ui",
+         "-F", "-"],
+        input=changelog_text,
+        text=True,
+    )
+    print(f"Draft created at: {output_string}")
+    print("Please review, then edit it and click 'Publish release'.")
+
+
+def get_changelog():
+    changelog_text = ""
+    in_changelog_text = False
+    version = ""
+    with open("CHANGELOG.md") as f:
+        for line in f:
+            m = release_header_pattern.match(line)
+
+            if m is not None:
+                # Found the first release.
+                if not in_changelog_text:
+                    in_changelog_text = True
+                    version = m.group(1)
+                else:
+                    # Found the next release.
+                    break
+            elif in_changelog_text:
+                changelog_text += line
+
+    return changelog_text, version
+
+
+if __name__ == "__main__":
+    main()