[IMP] fetchmail, on demand cron

enable a 3 micro hz cron only if needed as we want to lower the maximum
cron frequency in default addons to 1 micro hz

bzr revid: al@openerp.com-20130405024213-ll6t26j685rati5a

addons/fetchmail/fetchmail.py

@@ -90,7 +90,6 @@ class fetchmail_server(osv.osv):
         'script': '/mail/static/scripts/openerp_mailgate.py',
     }
 
-
     def onchange_server_type(self, cr, uid, ids, server_type=False, ssl=False, object_id=False):
         port = 0
         values = {}
@@ -176,7 +175,7 @@ openerp_mailgate: "|/path/to/openerp-mailgate.py --host=localhost -u %(uid)d -p
 
     def _fetch_mails(self, cr, uid, ids=False, context=None):
         if not ids:
-            ids = self.search(cr, uid, [('state','=','done')])
+            ids = self.search(cr, uid, [('state','=','done'),('type','in',['pop','imap'])])
         return self.fetch_mail(cr, uid, ids, context=context)
 
     def fetch_mail(self, cr, uid, ids, context=None):
@@ -241,6 +240,26 @@ openerp_mailgate: "|/path/to/openerp-mailgate.py --host=localhost -u %(uid)d -p
             server.write({'date': time.strftime(tools.DEFAULT_SERVER_DATETIME_FORMAT)})
         return True
 
+    def cron_update(self, cr, uid, context=None):
+        # Enabled/Disable cron based on the number of 'done' server of type pop or imap
+        ids = self.search(cr, uid, [('state','=','done'),('type','in',['pop','imap'])])
+        try:
+            cron_id = self.pool.get('ir.model.data').get_object_reference(cr, uid, 'fetchmail', 'ir_cron_mail_gateway_action')[1]
+            self.pool.get('ir.cron').write(cr, 1, [cron_id], {'active': bool(ids)})
+        except ValueError:
+            # Nevermind if default cron cannot be found
+            pass
+
+    def create(self, cr, uid, values, context=None):
+        res = super(fetchmail_server, self).create(cr, uid, values, context=context)
+        self.cron_update(cr, uid, context=context)
+        return res
+
+    def write(self, cr, uid, ids, values, context=None):
+        res = super(fetchmail_server, self).write(cr, uid, ids, values, context=context)
+        self.cron_update(cr, uid, context=context)
+        return res
+
 class mail_mail(osv.osv):
     _inherit = "mail.mail"
     _columns = {

addons/fetchmail/fetchmail_data.xml

@@ -10,6 +10,8 @@
             <field name="model">fetchmail.server</field>
             <field name="function">_fetch_mails</field>
             <field name="args">()</field>
+            <!-- Active flag is set on fetchmail_server.create/write -->
+            <field name="active" eval="False"/>
         </record>
     </data>
 </openerp>