add a ``max_page`` option to github source

also update README for other minor issue.

README.rst

@@ -286,9 +286,14 @@ use_latest_release
   includes both annotated tags and lightweight ones.
 
 use_max_tag
-  Set this to ``true`` to check for the max tag on GitHub. Unlike ``use_latest_release``,
-  this option includes both annotated tags and lightweight ones, and return the biggest one
-  sorted by ``pkg_resources.parse_version``.
+  Set this to ``true`` to check for the max tag on GitHub. Unlike
+  ``use_latest_release``, this option includes both annotated tags and
+  lightweight ones, and return the largest one sorted by the
+  ``sort_version_key`` option.
+
+max_page
+  How many pages do we search for the max tag? Default is 3. This works when
+  ``use_max_tag`` is set.
 
 proxy
   The HTTP proxy to use. The format is ``host:port``, e.g. ``localhost:8087``.
@@ -300,7 +305,7 @@ An environment variable ``NVCHECKER_GITHUB_TOKEN`` or a key named ``github``
 can be set to a GitHub OAuth token in order to request more frequently than
 anonymously.
 
-This source supports `list options`_ when ``use_latest_release`` or ``use_max_tag`` is set.
+This source supports `list options`_ when ``use_max_tag`` is set.
 
 Check BitBucket
 ---------------

nvchecker/source/github.py

@@ -62,6 +62,7 @@ async def get_version_real(name, conf, **kwargs):
     return await max_tag(partial(
       session.get, headers=headers, **kwargs),
       url, name, ignored_tags, include_tags_pattern,
+      max_page = conf.get("max_page", 3),
     )
 
   async with session.get(url, headers=headers, **kwargs) as res:
@@ -84,11 +85,12 @@ async def get_version_real(name, conf, **kwargs):
   return version
 
 async def max_tag(
-  getter, url, name, ignored_tags, include_tags_pattern,
+  getter, url, name, ignored_tags, include_tags_pattern, max_page,
 ):
   # paging is needed
+  tags = []
 
-  while True:
+  for _ in range(max_page):
     async with getter(url) as res:
       logger.debug('X-RateLimit-Remaining',
                     n=res.headers.get('X-RateLimit-Remaining'))
@@ -100,7 +102,7 @@ async def max_tag(
       data = [x for x in data
               if re.search(include_tags_pattern, x)]
     if data:
-      return data
+      tags += data
     else:
       next_page_url = get_next_page_url(links)
       if not next_page_url:
@@ -111,7 +113,7 @@ async def max_tag(
   logger.error('No tag found in upstream repository.',
                 name=name,
                 include_tags_pattern=include_tags_pattern)
-  return
+  return tags
 
 def get_next_page_url(links):
   links = links.split(', ')