1 files changed, 88 insertions, 0 deletions
diff --git a/google_appengine/lib/django/django/core/paginator.py b/google_appengine/lib/django/django/core/paginator.py
new file mode 100755
index 0000000..380808a
--- /dev/null
+++ b/google_appengine/lib/django/django/core/paginator.py
@@ -0,0 +1,88 @@
+class InvalidPage(Exception):
+    pass
+
+class ObjectPaginator(object):
+    """
+    This class makes pagination easy. Feed it a QuerySet or list, plus the number
+    of objects you want on each page. Then read the hits and pages properties to
+    see how many pages it involves. Call get_page with a page number (starting
+    at 0) to get back a list of objects for that page.
+
+    Finally, check if a page number has a next/prev page using
+    has_next_page(page_number) and has_previous_page(page_number).
+    
+    Use orphans to avoid small final pages. For example:
+    13 records, num_per_page=10, orphans=2 --> pages==2, len(self.get_page(0))==10
+    12 records, num_per_page=10, orphans=2 --> pages==1, len(self.get_page(0))==12
+    """
+    def __init__(self, query_set, num_per_page, orphans=0):
+        self.query_set = query_set
+        self.num_per_page = num_per_page
+        self.orphans = orphans
+        self._hits = self._pages = None
+
+    def validate_page_number(self, page_number):
+        try:
+            page_number = int(page_number)
+        except ValueError:
+            raise InvalidPage
+        if page_number < 0 or page_number > self.pages - 1:
+            raise InvalidPage
+        return page_number
+
+    def get_page(self, page_number):
+        page_number = self.validate_page_number(page_number)
+        bottom = page_number * self.num_per_page
+        top = bottom + self.num_per_page
+        if top + self.orphans >= self.hits:
+            top = self.hits
+        return self.query_set[bottom:top]
+
+    def has_next_page(self, page_number):
+        "Does page $page_number have a 'next' page?"
+        return page_number < self.pages - 1
+
+    def has_previous_page(self, page_number):
+        return page_number > 0
+
+    def first_on_page(self, page_number):
+        """
+        Returns the 1-based index of the first object on the given page,
+        relative to total objects found (hits).
+        """
+        page_number = self.validate_page_number(page_number)
+        return (self.num_per_page * page_number) + 1
+
+    def last_on_page(self, page_number):
+        """
+        Returns the 1-based index of the last object on the given page,
+        relative to total objects found (hits).
+        """
+        page_number = self.validate_page_number(page_number)
+        page_number += 1   # 1-base
+        if page_number == self.pages:
+            return self.hits
+        return page_number * self.num_per_page
+
+    def _get_hits(self):
+        if self._hits is None:
+            # Try .count() or fall back to len().
+            try:
+                self._hits = int(self.query_set.count())
+            except (AttributeError, TypeError, ValueError):
+                # AttributeError if query_set has no object count.
+                # TypeError if query_set.count() required arguments.
+                # ValueError if int() fails.
+                self._hits = len(self.query_set)
+        return self._hits
+
+    def _get_pages(self):
+        if self._pages is None:
+            hits = (self.hits - 1 - self.orphans)
+            if hits < 1:
+                hits = 0
+            self._pages = hits // self.num_per_page + 1
+        return self._pages
+
+    hits = property(_get_hits)
+    pages = property(_get_pages)