add clip manager

pandora/clip/managers.py

@@ -0,0 +1,164 @@
+# -*- coding: utf-8 -*-
+# vi:si:et:sw=4:sts=4:ts=4
+from django.db.models import Q, Manager
+from django.conf import settings
+
+from ox.django.query import QuerySet
+import ox
+
+def parseCondition(condition, user):
+    '''
+    condition: {
+            value: "war"
+    }
+    or
+    condition: {
+            key: "year",
+            value: "1970-1980,
+            operator: "!="
+    }
+    '''
+    k = condition.get('key', 'name')
+    k = {
+        'user': 'annotations__user__username',
+        'place': 'annotations__places__id',
+        'event': 'annotations__events__id',
+        'in': 'start',
+        'out': 'end',
+        'id': 'public_id',
+    }.get(k, k)
+    if not k:
+        k = 'name'
+    v = condition['value']
+    op = condition.get('operator')
+    if not op:
+        op = ''
+    if op.startswith('!'):
+        op = op[1:]
+        exclude = True
+    else:
+        exclude = False
+    if op == '-':
+        q = parseCondition({'key': k, 'value': v[0], 'operator': '>='}, user) \
+            & parseCondition({'key': k, 'value': v[1], 'operator': '<'}, user)
+        if exclude:
+            return ~q
+        else:
+            return q
+    if k.endswith('__id'):
+        v = ox.from26(v)
+    if isinstance(v, bool): #featured and public flag
+        key = k
+    elif k in ('lat', 'lng', 'area', 'south', 'west', 'north', 'east', 'matches',
+               'id') or k.endswith('__id'):
+        key = "%s%s" % (k, {
+            '>': '__gt',
+            '>=': '__gte',
+            '<': '__lt',
+            '<=': '__lte',
+        }.get(op, ''))
+    else:
+        key = "%s%s" % (k, {
+            '>': '__gt',
+            '>=': '__gte',
+            '<': '__lt',
+            '<=': '__lte',
+            '==': '__iexact',
+            '=': '__icontains',
+            '^': '__istartswith',
+            '$': '__iendswith',
+        }.get(op, '__icontains'))
+
+    key = str(key)
+    print key, v, exclude
+    if exclude:
+        q = ~Q(**{key: v})
+    else:
+        q = Q(**{key: v})
+    return q
+
+def parseConditions(conditions, operator, user):
+    '''
+    conditions: [
+        {
+            value: "war"
+        }
+        {
+            key: "year",
+            value: "1970-1980,
+            operator: "!="
+        },
+        {
+            key: "country",
+            value: "f",
+            operator: "^"
+        }
+    ],
+    operator: "&"
+    '''
+    conn = []
+    for condition in conditions:
+        if 'conditions' in condition:
+            q = parseConditions(condition['conditions'],
+                             condition.get('operator', '&'), user)
+            if q:
+                conn.append(q)
+            pass
+        else:
+            conn.append(parseCondition(condition, user))
+    if conn:
+        q = conn[0]
+        for c in conn[1:]:
+            if operator == '|':
+                q = q | c
+            else:
+                q = q & c
+        return q
+    return None
+
+
+
+class ClipManager(Manager):
+
+    def get_query_set(self):
+        return QuerySet(self.model)
+
+    def find(self, data, user):
+        '''
+            query: {
+                conditions: [
+                    {
+                        value: "war"
+                    }
+                    {
+                        key: "year",
+                        value: "1970-1980,
+                        operator: "!="
+                    },
+                    {
+                        key: "country",
+                        value: "f",
+                        operator: "^"
+                    }
+                ],
+                operator: "&"
+            }
+        '''
+
+        #join query with operator
+        qs = self.get_query_set()
+        
+        conditions = parseConditions(data.get('query', {}).get('conditions', []),
+                                     data.get('query', {}).get('operator', '&'),
+                                     user)
+        if conditions:
+            qs = qs.filter(conditions)
+        if 'keys' in data:
+            public_layers = [l['id']
+                             for l in filter(lambda l: not l.get('private', False),
+                                             settings.CONFIG['layers'])]
+            filter_layers = filter(lambda k: k in public_layers, data['keys'])
+            if filter_layers:
+                qs = qs.filter(annotations__layer__name__in=filter_layers)
+        qs = qs.distinct()
+        return qs