Added support for max_age.

[zzz-spline-frontpage.git] / splinext / frontpage / controllers / frontpage.py

diff --git a/splinext/frontpage/controllers/frontpage.py b/splinext/frontpage/controllers/frontpage.py
index 959f5fb..5aba8c5 100644 (file)
--- a/splinext/frontpage/controllers/frontpage.py
+++ b/splinext/frontpage/controllers/frontpage.py
@@ -1,4 +1,7 @@
+from collections import defaultdict
+import datetime
 import logging
+import re
 
 from pylons import config, request, response, session, tmpl_context as c, url
 from pylons.controllers.util import abort, redirect_to
@@ -16,17 +19,102 @@ class FrontPageController(BaseController):
     def index(self):
         """Magicaltastic front page.
 
-        Plugins can register things to appear on it, somehow.
+        Plugins can register a hook called 'frontpage_updates_<type>' to add
+        updates to the front page.  `<type>` is an arbitrary string indicating
+        the sort of update the plugin knows how to handle; for example,
+        spline-forum has a `frontpage_updates_forum` hook for posting news from
+        a specific forum.
+
+        Hook handlers should return a list of FrontPageUpdate objects.
+
+        Standard hook parameters are:
+        `limit`, the maximum number of items that should ever be returned.
+        `max_age`, the number of seconds after which items expire.
+        `title`, a name for the source.
+        `icon`, an icon to show next to its name.
+
+        `limit` and `max_age` are also global options.
+
+        Updates are configured in the .ini like so:
+
+            spline-frontpage.sources.foo = updatetype
+            spline-frontpage.sources.foo.opt1 = val1
+            spline-frontpage.sources.foo.opt2 = val2
+
+        Note that the 'foo' name is completely arbitrary and is only used for
+        grouping options together.  This will result in a call to:
+
+            run_hooks('frontpage_updates_updatetype', opt1=val1, opt2=val2)
 
         Local plugins can override the fairly simple index.mako template to
         customize the front page layout.
         """
-        # Hooks should return a list of FrontPageUpdate objects, making this
-        # return value a list of lists
-        updates_lol = run_hooks('frontpage_updates', limit=10)
-        updates = sum(updates_lol, [])
-        updates.sort(key=lambda obj: obj.time)
+        # XXX no reason to do this on the fly; cache it on server startup
+        update_config = defaultdict(dict)  # source_name => config
+        key_rx = re.compile(
+            '(?x) ^ spline-frontpage [.] sources [.] (\w+) (?: [.] (\w+) )? $')
+        for key, val in config.iteritems():
+            match = key_rx.match(key)
+            if not match:
+                continue
+
+            source_name, subkey = match.groups()
+            if not subkey:
+                # This is the type declaration; use a special key
+                subkey = '__type__'
+
+            if subkey in ('limit', 'max_age'):
+                val = int(val)
+            update_config[source_name][subkey] = val
+
+        global_limit = int(config.get('spline-frontpage.limit', 10))
+        now = datetime.datetime.now()
+        try:
+            global_max_age = now - datetime.timedelta(
+                seconds=int(config['spline-frontpage.max_age']))
+        except KeyError:
+            global_max_age = None
+
+        # Ask plugins to deal with this stuff for us!
+        updates = []
+        for source, source_config in update_config.iteritems():
+            hook_name = 'frontpage_updates_' + source_config['__type__']
+
+            # Merge with the global config
+            merged_config = source_config.copy()
+            del merged_config['__type__']
+
+            merged_config['limit'] = min(
+                merged_config.get('limit', global_limit),
+                global_limit,
+            )
+
+            try:
+                local_max_age = now - datetime.timedelta(
+                    seconds=merged_config['max_age'])
+            except KeyError:
+                local_max_age = None
+
+            if global_max_age and local_max_age:
+                merged_config['max_age'] = max(global_max_age, local_max_age)
+            else:
+                merged_config['max_age'] = global_max_age or local_max_age
+
+            # Hooks should return a list of FrontPageUpdate-like objects,
+            # making this return value a list of lists
+            updates_lol = run_hooks(hook_name, **merged_config)
+            updates += sum(updates_lol, [])
+
+            # Little optimization: maximum age effectively becomes the age of
+            # the oldest thing that would still appear on the page, as anything
+            # older would drop off the end no matter what.
+            # So sort by descending time and crop each iteration...
+            updates.sort(key=lambda obj: obj.time, reverse=True)
+            updates = updates[:global_limit]
+
+            if updates:
+                global_max_age = updates[-1].time
 
-        c.updates = updates[0:10]
+        c.updates = updates
 
         return render('/index.mako')