Merge branch 'dev/db-groupby' into dev/dbv0.2.0

3 files changed, 81 insertions, 7 deletions

diff --git a/db.py b/db.py
new file mode 100644
index 0000000..2d4d320
--- /dev/null
+++ b/db.py
@@ -0,0 +1,60 @@
+from django.db import connections
+from django.db.models import Manager
+from django.db.models.query import QuerySet
+from django.db.models.sql.compiler import SQLCompiler
+from django.db.models.sql.query import Query
+from django.db.models.sql.where import WhereNode
+
+
+class GroupedCompiler(SQLCompiler):
+    def get_group_by(self, select, order_by):
+        result = super(GroupedCompiler, self).get_group_by(select, order_by)
+        expressions = []
+        for expr in self.query.real_group_by:
+            ref = expr if hasattr(expr, "as_sql") else self.query.resolve_ref(expr)
+            sql, params = self.compile(ref)
+            result.append((sql, params))
+
+        return result
+
+
+class GroupedQuery(Query):
+    def __init__(self, model, where=WhereNode):
+        super(GroupedQuery, self).__init__(model, where)
+        self.real_group_by = []
+
+    def clone(self, klass=None, memo=None, **kwargs):
+        obj = super(GroupedQuery, self).clone(klass, memo, **kwargs)
+        obj.real_group_by = self.real_group_by[:]
+        return obj
+
+    def add_grouping(self, *grouping):
+        self.real_group_by.extend(grouping)
+
+    def clear_grouping(self):
+        self.real_group_by = []
+
+    def get_compiler(self, using=None, connection=None):
+        if using is None and connection is None:
+            raise ValueError("Need either using or connection")
+        if using:
+            connection = connections[using]
+        return GroupedCompiler(self, connection, using)
+
+
+class GroupedQuerySet(QuerySet):
+    def __init__(self, model=None, query=None, using=None, hints=None):
+        super(GroupedQuerySet, self).__init__(model, query, using, hints)
+        self.query = query or GroupedQuery(self.model)
+
+    def group_by(self, *field_names):
+        obj = self._clone()
+        obj.query.clear_grouping()
+        obj.query.add_grouping(*field_names)
+        return obj
+
+
+class GroupedManager(Manager):
+    def __init__(self):
+        super(GroupedManager, self).__init__()
+        self._queryset_class = GroupedQuerySet
diff --git a/models.py b/models.py
index 9cb3bca..a2d4281 100644
--- a/models.py
+++ b/models.py
@@ -1,7 +1,11 @@
-from django.db import models
+from django.db import connection, models
 from django.db.models import Q
+from django.db.models.expressions import RawSQL
+from django.db.models.functions import Extract, ExtractYear
 from django.utils.text import slugify
 
+from .db import GroupedManager
+
 import hashlib
 import os
 
@@ -107,12 +111,22 @@ class Room(models.Model):
         verbose_name_plural = "salles"
 
 
-class CourseManager(models.Manager):
+class CourseManager(GroupedManager):
+    def __get_weeks(self, qs):
+        extractYear = ExtractYear("begin")
+        qs = qs.group_by("groups", "year", "week").order_by("groups__name", "year", "week")
+
+        if connection.vendor == "postgresql":
+            return qs.annotate(week=ExtractWeek("begin"), year=extractYear)
+        else:
+            return qs.annotate(week=RawSQL("""cast(strftime("%%W", "begin") as integer)""", []), year=extractYear)
+
     def get_courses_for_group(self, group, **filters):
         return self.get_queryset().filter(Q(groups__td__isnull=True) | Q(groups__td=group.td), Q(groups__tp__isnull=True) | Q(groups__tp=group.tp), groups__mention=group.mention, groups__subgroup=group.subgroup, **filters).order_by("begin")
 
-    def get_weeks(self, date):
-        return self.get_queryset().raw("select edt_course.id, cast(strftime('%%W', begin) as integer) as week, cast(strftime('%%Y', begin) as integer) as year, edt_group.name, edt_group.timetable_id, edt_group.mention, edt_group.subgroup, edt_group.td, edt_group.tp, edt_group.slug, edt_group.id as group_id from edt_course inner join edt_course_groups on (edt_course.id = edt_course_groups.course_id) inner join edt_group on (edt_course_groups.group_id = edt_group.id) where begin >= %s group by group_id, week, year order by group_id, year, week", [date])
+    def get_weeks(self, **criteria):
+        qs = self.get_queryset().filter(**criteria)
+        return self.__get_weeks(qs)
 
 
 class Course(models.Model):
diff --git a/views.py b/views.py
index c549cfb..e883e9d 100644
--- a/views.py
+++ b/views.py
@@ -18,15 +18,15 @@ def index(request):
 
     current_year, current_week, _ = timezone.now().isocalendar()
     start, _ = get_week(current_year, current_week)
-    groups_weeks = Course.objects.get_weeks(start)
+    groups_weeks = Course.objects.get_weeks(begin__gte=start).values("groups__timetable", "groups__mention", "groups__subgroup", "groups__td", "groups__tp", "year", "week")
 
     for group in groups:
         for group_week in groups_weeks:
-            if group.corresponds_to(group_week.timetable_id, group_week.mention, group_week.subgroup, group_week.td, group_week.tp):
+            if group.corresponds_to(group_week["groups__timetable"], group_week["groups__mention"], group_week["groups__subgroup"], group_week["groups__td"], group_week["groups__tp"]):
                 if not hasattr(group, "weeks"):
                     group.weeks = []
 
-                date, _ = get_week(group_week.year, group_week.week)
+                date, _ = get_week(group_week["year"], group_week["week"])
                 if date not in group.weeks:
                     group.weeks.append(date)