Cache all query carousels (#9807)

* Cache all QueryCarousels by shortening cache key prefix by md5 hashing `args` and `kwargs` for cache keys
* Include name of cached macro in cache key
* Option to prevent caching select carousels

Avoids caching the book page related works carousel, which is fetched
after the page loads.  Also prevents the homepage "Classic Books"
carousel from being cached, as the homepage itself is cached for the
same amount of time.

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Mek <michael.karpeles@gmail.com>

openlibrary/core/cache.py

@@ -1,6 +1,7 @@
 """Caching utilities.
 """
 
+import hashlib
 import random
 import string
 import time
@@ -59,6 +60,7 @@ def __init__(
         key_prefix: str | None = None,
         timeout: int = MINUTE_SECS,
         prethread: Callable | None = None,
+        hash_args: bool = False,
     ):
         """Creates a new memoized function for ``f``."""
         self.f = f
@@ -70,6 +72,7 @@ def __init__(
         self.stats = web.storage(calls=0, hits=0, updates=0, async_updates=0)
         self.active_threads: dict = {}
         self.prethread = prethread
+        self.hash_args = hash_args
 
     def _get_memcache(self):
         if self._memcache is None:
@@ -177,20 +180,21 @@ def join_threads(self):
             thread.join()
 
     def encode_args(self, args, kw=None):
+        """Encodes arguments to construct the memcache key."""
         kw = kw or {}
-        """Encodes arguments to construct the memcache key.
-        """
+
         # strip [ and ] from key
         a = self.json_encode(list(args))[1:-1]
 
         if kw:
-            return a + "-" + self.json_encode(kw)
-        else:
-            return a
+            a = a + "-" + self.json_encode(kw)
+        if self.hash_args:
+            return f"{hashlib.md5(a.encode('utf-8')).hexdigest()}"
+        return a
 
     def compute_key(self, args, kw):
         """Computes memcache key for storing result of function call with given arguments."""
-        key = self.key_prefix + "-" + self.encode_args(args, kw)
+        key = self.key_prefix + "$" + self.encode_args(args, kw)
         return key.replace(
             " ", "_"
         )  # XXX: temporary fix to handle spaces in the arguments

openlibrary/i18n/messages.pot

@@ -7457,7 +7457,7 @@ msgstr ""
 msgid "This graph charts editions published on this subject."
 msgstr ""
 
-#: QueryCarousel.html
+#: RawQueryCarousel.html
 msgid "Search collection"
 msgstr ""
 

openlibrary/macros/QueryCarousel.html

@@ -1,4 +1,4 @@
-$def with(query, title=None, sort='new', key='', limit=20, search=False, has_fulltext_only=True, url=None, layout='carousel')
+$def with(query, title=None, sort='new', key='', limit=20, search=False, has_fulltext_only=True, url=None, layout='carousel', use_cache=True)
 
 $# Takes following parameters
 $# * query (str) -- Any arbitrary Open Library search query, e.g. subject:"Textbooks"
@@ -9,26 +9,7 @@
 $# * search (bool) -- whether to include search within collection
 $# * layout (str) -- layout type, default 'carousel', currently also supports 'grid'
 
-$# Enable search within this query
-$if search:
-  <form action="/search" class="olform pagesearchbox">
-    <input type="hidden" name="q" value="$query"/>
-    $if has_fulltext_only:
-      <input type="hidden" name="has_fulltext" value="true"/>
-    <input type="text" placeholder="$_('Search collection')" name="q2"/>
-    <input type="submit"/>
-  </form>
-
-$code:
-  # Limit to just fields needed to render carousels
-  params = { 'q': query, 'fields': 'key,title,subtitle,author_name,cover_i,ia,availability,id_project_gutenberg,id_librivox,id_standard_ebooks,id_openstax' }
-  # Don't need fields in the search UI url, since they don't do anything there
-  url = url or "/search?" + urlencode({'q': query})
-  if has_fulltext_only:
-    params['has_fulltext'] = 'true'
-
-  results = work_search(params, sort=sort, limit=limit, facet=False)
-  books = [storage(b) for b in (results.get('docs', []))]
-  load_more = {"url": "/search.json?" + urlencode(params), "limit": limit }
-
-$:render_template("books/custom_carousel", books=books, title=title, url=url, key=key, load_more=load_more, layout=layout)
+$if use_cache:
+    $:macros.CacheableMacro("RawQueryCarousel", query, title=title, sort=sort, key=key, limit=limit, search=search, has_fulltext_only=has_fulltext_only, url=url, layout=layout)
+$else:
+    $:macros.RawQueryCarousel(query, title=title, sort=sort, key=key, limit=limit, search=search, has_fulltext_only=has_fulltext_only, url=url, layout=layout)

openlibrary/macros/RawQueryCarousel.html

@@ -0,0 +1,34 @@
+$def with(query, title=None, sort='new', key='', limit=20, search=False, has_fulltext_only=True, url=None, layout='carousel')
+
+$# Takes following parameters
+$# * query (str) -- Any arbitrary Open Library search query, e.g. subject:"Textbooks"
+$# * title (str) -- A title to show above the carousel (links to /search?q=query)
+$# * sort (str) -- optional sort param defined within work_search.py `work_search`
+$# * key (str) -- unique name of the carousel in analytics
+$# * limit (int) -- initial number of books to pull
+$# * search (bool) -- whether to include search within collection
+$# * layout (str) -- layout type, default 'carousel', currently also supports 'grid'
+
+$# Enable search within this query
+$if search:
+  <form action="/search" class="olform pagesearchbox">
+    <input type="hidden" name="q" value="$query"/>
+    $if has_fulltext_only:
+      <input type="hidden" name="has_fulltext" value="true"/>
+    <input type="text" placeholder="$_('Search collection')" name="q2"/>
+    <input type="submit"/>
+  </form>
+
+$code:
+  # Limit to just fields needed to render carousels
+  params = { 'q': query, 'fields': 'key,title,subtitle,author_name,cover_i,ia,availability,id_project_gutenberg,id_librivox,id_standard_ebooks,id_openstax' }
+  # Don't need fields in the search UI url, since they don't do anything there
+  url = url or "/search?" + urlencode({'q': query})
+  if has_fulltext_only:
+    params['has_fulltext'] = 'true'
+
+  results = work_search(params, sort=sort, limit=limit, facet=False)
+  books = [storage(b) for b in (results.get('docs', []))]
+  load_more = {"url": "/search.json?" + urlencode(params), "limit": limit }
+
+$:render_template("books/custom_carousel", books=books, title=title, url=url, key=key, load_more=load_more, layout=layout)

openlibrary/plugins/upstream/utils.py

@@ -218,25 +218,26 @@ def render_macro(name, args, **kwargs):
 
 
 @public
-def render_cached_macro(name, args: tuple, **kwargs):
+def render_cached_macro(name: str, args: tuple, **kwargs):
     from openlibrary.plugins.openlibrary.home import caching_prethread
 
-    def get_key():
+    def get_key_prefix():
         lang = web.ctx.lang
-        pd = web.cookies().get('pd', False)
-        key = f'{name}.{lang}'
-        if pd:
-            key += '.pd'
-        for arg in args:
-            key += f'.{arg}'
-        for k, v in kwargs.items():
-            key += f'.{k}:{v}'
-        return key
+        key_prefix = f'{name}.{lang}'
+        if web.cookies().get('pd', False):
+            key_prefix += '.pd'
+        if web.cookies().get('sfw', ''):
+            key_prefix += '.sfw'
+        return key_prefix
 
     five_minutes = 5 * 60
-    key = get_key()
+    key_prefix = get_key_prefix()
     mc = cache.memcache_memoize(
-        render_macro, key, timeout=five_minutes, prethread=caching_prethread()
+        render_macro,
+        key_prefix=key_prefix,
+        timeout=five_minutes,
+        prethread=caching_prethread(),
+        hash_args=True,  # this avoids cache key length overflow
     )
 
     try:

openlibrary/templates/books/RelatedWorksCarousel.html

@@ -12,12 +12,12 @@
             $ )
             $if author_keys:
                 $ query += ' -author_key:(%s)' % ' OR '.join(['%s' % a for a in author_keys])
-            $:macros.QueryCarousel(query=query, title=_("You might also like"), key="related-subjects-carousel", limit=12)
+            $:macros.QueryCarousel(query=query, title=_("You might also like"), key="related-subjects-carousel", limit=12, use_cache=False)
         $if author_keys:
             $ query = 'ebook_access:[borrowable TO *] -key:"%s" author_key:(%s)' % (
             $    work.key,
             $    ' OR '.join(['%s' % a for a in author_keys]),
             $ )
             $ title = ungettext("More by this author", "More by these authors", len(author_keys))
-            $:macros.QueryCarousel(query=query, title=title, key="related-authors-carousel", limit=12)
+            $:macros.QueryCarousel(query=query, title=title, key="related-authors-carousel", limit=12, use_cache=False)
     </div>

openlibrary/templates/home/index.html

@@ -22,7 +22,7 @@
   $if not test:
     $:render_template("books/custom_carousel", key="trending", books=get_trending_books(books_only=True, since_days=0, since_hours=24, minimum=3, sort_by_count=False), title=_('Trending Books'), url="/trending/daily", test=test, load_more={"url": "/trending/hours.json?hours=24&minimum=3&sort_by_count=false", "mode": "page", "limit": 18})
 
-    $:macros.QueryCarousel(query="ddc:8* first_publish_year:[* TO 1950] publish_year:[2000 TO *] NOT public_scan_b:false", title=_('Classic Books'), key="public_domain", url="/read", sort='random.hourly')
+    $:macros.QueryCarousel(query="ddc:8* first_publish_year:[* TO 1950] publish_year:[2000 TO *] NOT public_scan_b:false", title=_('Classic Books'), key="public_domain", url="/read", sort='random.hourly', use_cache=False)
 
   $:render_template("home/custom_ia_carousel", title=_('Books We Love'), key="staff_picks", query='languageSorter:("English")', subject="openlibrary_staff_picks", sorts=["lending___last_browse desc"], limit=18, test=test)