Prepare Command.CommandResult for reuse, start work on CommandResultC…

…ache

mailpile/command_cache.py

@@ -0,0 +1,48 @@
+import time
+
+import mailpile.util
+from mailpile.i18n import gettext as _
+from mailpile.i18n import ngettext as _n
+from mailpile.util import *
+
+
+class CommandResultCache(object):
+    #
+    # This is a persistent cache of commands and results we may want
+    # to refresh in the background and/or reuse.
+    #
+    # The way this works:
+    #     - Cache-able commands generate a fingerprint describing themselves.
+    #     - If the fingerprint is found in cache, reuse the result object.
+    #     - Otherwise, run, generate a list of requirements and cache all of:
+    #       the command object itself, the requirements, the result object.
+    #     - Internal state changes (tag ops, new mail, etc.) call mark_dirty()
+    #       describing which assets (requirements) have changed.
+    #     - Periodically, the cache is refreshed, which re-runs any dirtied
+    #       commands and fires events notifying the UI about changes.
+    #
+
+    def __init__(self):
+        self.cache = {}
+        self.dirty = set()
+
+    def cache_result(self, fprint, expires, req, command_obj, result_obj):
+        self.cache[fprint] = (expires, req, command_obj, result_obj)
+
+    def mark_dirty(self, requirement):
+        for fprint, (e, r, co, ro) in self.cache.iteritems():
+            if req in r:
+                self.dirty.add(fprint)
+
+    def refresh(self, extend=60):
+        now = time.time()
+        expired = set([f for f in self.cache if self.cache[f][0] < now])
+        for fp in expired:
+            del self.cache[fp]
+
+        dirty, self.dirty = self.dirty, set()
+        for fprint in (dirty - expired):
+            exp, req, co, ro = self.cache[fprint]
+            ro = co.refresh()
+            self.cache[fprint] = (exp + extend, req, co, ro)
+

mailpile/commands.py

@@ -33,7 +33,7 @@
 from mailpile.vcard import AddressInfo
 
 
-class Command:
+class Command(object):
     """Generic command object all others inherit from"""
     SYNOPSIS = (None,     # CLI shortcode, e.g. A:
                 None,     # CLI shortname, e.g. add
@@ -84,10 +84,30 @@ def __init__(self, command_obj, session,
             self.error_info = {}
             self.error_info.update(error_info)
             self.message = message
+            self.rendered = {}
+            self.renderers = {
+                'json': self.as_json,
+                'html': self.as_html,
+                'text': self.as_text,
+                'css': self.as_css,
+                'rss': self.as_rss,
+                'xml': self.as_xml,
+                'txt': self.as_txt,
+                'js': self.as_js
+            }
 
         def __nonzero__(self):
             return (self.result and True or False)
 
+        def as_(self, what, *args, **kwargs):
+            if args or kwargs:
+                # Args render things un-cacheable.
+                return self.renderers.get(what)(*args, **kwargs)
+
+            if what not in self.rendered:
+                self.rendered[what] = self.renderers.get(what, self.as_text)()
+            return self.rendered[what]
+
         def as_text(self):
             if isinstance(self.result, bool):
                 happy = '%s: %s' % (self.result and _('OK') or _('Failed'),
@@ -152,6 +172,13 @@ def as_txt(self, template=None):
             return self.as_template('txt', template)
 
         def as_template(self, etype, template=None):
+            what = ''.join((etype, '/' if template else '', template or ''))
+            for e in ('jhtml', 'jjs', 'jcss', 'jxml', 'jrss'):
+                if self.session.ui.render_mode.endswith(e):
+                    what += ':content'
+            if what in self.rendered:
+                return self.rendered[what]
+
             tpath = self.command_obj.template_path(
                 etype, template_id=self.template_id, template=template)
 
@@ -163,13 +190,14 @@ def render():
                 return self.session.ui.render_web(
                     self.session.config, [tpath], data)
 
-            for e in ('jhtml', 'jjs', 'jcss', 'jxml', 'jrss'):
-                if self.session.ui.render_mode.endswith(e):
-                    data['render_mode'] = 'content'
-                    data['result'] = render()
-                    return self.session.ui.render_json(data)
+            if what.endswith(':content'):
+                data['render_mode'] = 'content'
+                data['result'] = render()
+                self.rendered[what] = self.session.ui.render_json(data)
+            else:
+                self.rendered[what] = render()
 
-            return render()
+            return self.rendered[what]
 
     def __init__(self, session, name=None, arg=None, data=None, async=False):
         self.session = session

mailpile/ui.py

@@ -336,7 +336,7 @@ def display_result(self, result):
         """Render command result objects to the user"""
         self._display_log('', level=self.LOG_RESULT)
         if self.render_mode == 'json':
-            return self._display_result(result.as_json())
+            return self._display_result(result.as_('json'))
         for suffix in ('css', 'html', 'js', 'rss', 'txt', 'xml'):
             if self.render_mode.endswith(suffix):
                 if self.render_mode in (suffix, 'j' + suffix):