Caches are valid rss feeds now! Yay!

lib.js

@@ -138,8 +138,11 @@ export const delayedFetch = async (url, options, courtesyWait = 5 * 1000) => {
   return await fetch(url, options)
 }
 
+export const getCacheFilename = (source) =>
+  source.name + '.xml'
+
 export const getCachePath = (source, { directory }) =>
-  Path.join(directory, source.name + '.xml')
+  Path.join(directory, getCacheFilename(source))
 
 export const cacheSource = (source, cache) =>
   write(getCachePath(source, cache), createCache(source, cache))
@@ -186,17 +189,16 @@ export const openCache = async (source, cache) => {
 export const buildCacheLink = source =>
   new URL('https://' + source.hostname)
 
-// TODO: Support atom links
-// https://validator.w3.org/feed/docs/warning/MissingAtomSelfLink.html
-// TODO: Add a description of some kind
 export const createCache = (source, cache) => `\
 <?xml version="1.0" encoding="UTF-8" ?>
-<rss version="2.0">
+<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">
 
 <channel>
 
 <title>${source.displayName}</title>
+<description>${source.description}</description>
 <link>${buildCacheLink(source)}</link>
+<atom:link href="${new URL(getCacheFilename(source), cache.directoryUrl)}" rel="self" type="application/rss+xml" />
 <pubDate>${new Date(source.latestPostDate).toUTCString()}</pubDate>
 <generator>rssssing</generator>
 ${source.posts.map(post => post.item.outerHTML.replaceAll(/\n\s*/g, '')).join('\n')}
@@ -582,6 +584,7 @@ export const tumblr = {
   createSource(user, courtesyWait, postReducerCallback, cache) {
     let lowercaseUser = user.toLowerCase()
     let source = {
+      description: `Aggregate feed for @${lowercaseUser} on tumblr.com`,
       hostname: lowercaseUser + '.tumblr.com',
       pathname: 'rss',
       courtesyWait,
@@ -621,6 +624,7 @@ export const tumblr = {
 export const nitter = {
   createSource(user, instances, courtesyWait, postReducerCallback, cache) {
     let source = {
+      description: `Aggregate feed for @${user} on twitter.com`,
       instances,
       pathname: user + '/rss',
       courtesyWait,