add rss content to post history and generate it when creating or editing a post

app/migrations.py

@@ -43,6 +43,7 @@ MIGRATIONS = [
     add_signature_format,
     create_default_bookmark_collections,
     add_display_name,
+    'ALTER TABLE "post_history" ADD COLUMN "content_rss" STRING DEFAULT NULL'
 ]
 
 def run_migrations():

app/routes/posts.py

@@ -2,7 +2,7 @@ from flask import (
     Blueprint, redirect, url_for, flash, render_template, request
     )
 from .users import login_required, get_active_user
-from ..lib.babycode import babycode_to_html, BABYCODE_VERSION
+from ..lib.babycode import babycode_to_html, babycode_to_rssxml, BABYCODE_VERSION
 from ..constants import InfoboxKind
 from ..db import db
 from ..models import Posts, PostHistory, Threads, Topics, Mentions
@@ -12,6 +12,7 @@ bp = Blueprint("posts", __name__, url_prefix = "/post")
 
 def create_post(thread_id, user_id, content, markup_language="babycode"):
     parsed_content = babycode_to_html(content)
+    parsed_rss = babycode_to_rssxml(content)
     with db.transaction():
         post = Posts.create({
             "thread_id": thread_id,
@@ -22,6 +23,7 @@ def create_post(thread_id, user_id, content, markup_language="babycode"):
         revision = PostHistory.create({
             "post_id": post.id,
             "content": parsed_content.result,
+            "content_rss": parsed_rss,
             "is_initial_revision": True,
             "original_markup": content,
             "markup_language": markup_language,
@@ -43,11 +45,13 @@ def create_post(thread_id, user_id, content, markup_language="babycode"):
 
 def update_post(post_id, new_content, markup_language='babycode'):
     parsed_content = babycode_to_html(new_content)
+    parsed_rss = babycode_to_rssxml(new_content)
     with db.transaction():
         post = Posts.find({'id': post_id})
         new_revision = PostHistory.create({
             'post_id': post.id,
             'content': parsed_content.result,
+            "content_rss": parsed_rss,
             'is_initial_revision': False,
             'original_markup': new_content,
             'markup_language': markup_language,