release: Add an update_release_calendar.py script

This script is for updating post version bump.

Acked-by: Eric Engestrom <eric.engestrom@intel.com>
Acked-by: Juan A. Suarez <jasuarez@igalia.com>

diff --git a/bin/post_version.py b/bin/post_version.py
new file mode 100755 (executable)
index 0000000..9afb37b
--- /dev/null
+++ b/bin/post_version.py
@@ -0,0 +1,122 @@
+#!/usr/bin/env python3
+# Copyright © 2019 Intel Corporation
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+"""Update the main page, release notes, and calendar."""
+
+import calendar
+import datetime
+import pathlib
+from lxml import (
+    etree,
+    html,
+)
+
+
+def calculate_previous_version(version: str, is_point: bool) -> str:
+    """Calculate the previous version to compare to.
+
+    In the case of -rc to final that verison is the previous .0 release,
+    (19.3.0 in the case of 20.0.0, for example). for point releases that is
+    the last point release. This value will be the same as the input value
+    for a poiont release, but different for a major release.
+    """
+    if '-' in version:
+        version = version.split('-')[0]
+    if is_point:
+        return version
+    base = version.split('.')
+    if base[1] == '0':
+        base[0] = str(int(base[0]) - 1)
+        base[1] = '3'
+    else:
+        base[1] = str(int(base[1]) - 1)
+    return '.'.join(base)
+
+
+def get_version() -> str:
+    v = pathlib.Path(__file__).parent.parent / 'VERSION'
+    with v.open('rt') as f:
+        raw_version = f.read().strip()
+    return raw_version.split('-')[0]
+
+
+def is_point_release() -> bool:
+    v = pathlib.Path(__file__).parent.parent / 'VERSION'
+    with v.open('rt') as f:
+        raw_version = f.read().strip()
+    return '-rc' not in raw_version
+
+
+def update_index(is_point: bool, version: str, previous_version: str) -> None:
+    p = pathlib.Path(__file__).parent.parent / 'docs' / 'index.html'
+    with p.open('rt') as f:
+        tree = html.parse(f)
+
+    news = tree.xpath('.//h1')[0]
+
+    date = datetime.date.today()
+    month = calendar.month_name[date.month]
+    header = etree.Element('h2')
+    header.text=f"{month} {date.day}, {date.year}"
+
+    body = etree.Element('p')
+    a = etree.SubElement(body, 'a', attrib={'href': f'relnotes/{previous_version}'})
+    a.text = f"Mesa {previous_version}"
+    if is_point:
+        a.tail = " is released. This is a bug fix release."
+    else:
+        a.tail = (" is released. This is a new development release. "
+                  "See the release notes for mor information about this release.")
+
+    root = news.getparent()
+    index = root.index(news) + 1
+    root.insert(index, body)
+    root.insert(index, header)
+
+    tree.write(p.as_posix(), method='html')
+
+
+def update_release_notes(previous_version: str) -> None:
+    p = pathlib.Path(__file__).parent.parent / 'docs' / 'relnotes.html'
+    with p.open('rt') as f:
+        tree = html.parse(f)
+
+    li = etree.Element('li')
+    a = etree.SubElement(li, 'a', href=f'relnotes/{previous_version}')
+    a.text = f'{previous_version} release notes'
+
+    ul = tree.xpath('.//ul')[0]
+    ul.insert(0, li)
+
+    tree.write(p.as_posix(), method='html')
+
+
+def main() -> None:
+    is_point = is_point_release()
+    version = get_version()
+    previous_version = calculate_previous_version(version, is_point)
+
+    update_index(is_point, version, previous_version)
+    update_release_notes(previous_version)
+
+
+if __name__ == "__main__":
+    main()