Fixed #897 - Ability to disable count queries and have back/fwd pager

flask_admin/contrib/mongoengine/view.py

@@ -484,7 +484,7 @@ class ModelView(BaseModelView):
             query = self._search(query, search)
 
         # Get count
-        count = query.count()
+        count = query.count() if not self.simple_list_pager else None
 
         # Sorting
         if sort_column:

flask_admin/contrib/peewee/view.py

@@ -339,7 +339,7 @@ class ModelView(BaseModelView):
                 query = f.apply(query, f.clean(value))
 
         # Get count
-        count = query.count()
+        count = query.count() if not self.simple_list_pager else None
 
         # Apply sorting
         if sort_column is not None:

flask_admin/contrib/pymongo/view.py

@@ -222,7 +222,7 @@ class ModelView(BaseModelView):
             query = self._search(query, search)
 
         # Get count
-        count = self.coll.find(query).count()
+        count = self.coll.find(query).count() if not self.simple_list_pager else None
 
         # Sorting
         sort_by = None

flask_admin/contrib/sqla/view.py

@@ -4,7 +4,7 @@ import warnings
 from sqlalchemy.orm.attributes import InstrumentedAttribute
 from sqlalchemy.orm import joinedload
 from sqlalchemy.sql.expression import desc
-from sqlalchemy import Column, Boolean, func, or_
+from sqlalchemy import Boolean, func, or_
 from sqlalchemy.exc import IntegrityError
 
 from flask import flash
@@ -765,7 +765,7 @@ class ModelView(BaseModelView):
         joins = set()
 
         query = self.get_query()
-        count_query = self.get_count_query()
+        count_query = self.get_count_query() if not self.simple_list_pager else None
 
         # Ignore eager-loaded relations (prevent unnecessary joins)
         # TODO: Separate join detection for query and count query?
@@ -781,6 +781,8 @@ class ModelView(BaseModelView):
                 for table in self._search_joins:
                     if table.name not in joins:
                         query = query.outerjoin(table)
+
+                        if count_query is not None:
                             count_query = count_query.outerjoin(table)
 
                         joins.add(table.name)
@@ -795,6 +797,8 @@ class ModelView(BaseModelView):
                 stmt = tools.parse_like_term(term)
                 filter_stmt = [c.ilike(stmt) for c in self._search_fields]
                 query = query.filter(or_(*filter_stmt))
+
+                if count_query is not None:
                     count_query = count_query.filter(or_(*filter_stmt))
 
         # Apply filters
@@ -811,15 +815,20 @@ class ModelView(BaseModelView):
                     for table in join_tables:
                         if table.name not in joins:
                             query = query.join(table)
+
+                            if count_query is not None:
                                 count_query = count_query.join(table)
+
                             joins.add(table.name)
 
                 # turn into python format with .clean() and apply filter
                 query = flt.apply(query, flt.clean(value))
+
+                if count_query is not None:
                     count_query = flt.apply(count_query, flt.clean(value))
 
-        # Calculate number of rows
-        count = count_query.scalar()
+        # Calculate number of rows if necessary
+        count = count_query.scalar() if count_query else None
 
         # Auto join
         for j in self._auto_joins:

flask_admin/model/base.py

@@ -321,6 +321,12 @@ class BaseModelView(BaseView, ActionsMixin):
         Controls if the primary key should be displayed in the list view.
     """
 
+    simple_list_pager = False
+    """
+        Enable or disable simple list pager.
+        If enabled, model interface would not run count query and will only show prev/next pager buttons.
+    """
+
     form = None
     """
         Form class. Override if you want to use custom form for your model.
@@ -1486,9 +1492,12 @@ class BaseModelView(BaseView, ActionsMixin):
                                     view_args.search, view_args.filters)
 
         # Calculate number of pages
+        if count is not None:
             num_pages = count // self.page_size
             if count % self.page_size != 0:
                 num_pages += 1
+        else:
+            num_pages = None
 
         # Various URL generation helpers
         def pager_url(p):
@@ -1531,6 +1540,7 @@ class BaseModelView(BaseView, ActionsMixin):
             pager_url=pager_url,
             num_pages=num_pages,
             page=view_args.page,
+            page_size=self.page_size,
 
             # Sorting
             sort_column=view_args.sort,

flask_admin/templates/bootstrap2/admin/lib.html

@@ -76,6 +76,31 @@
 {% endif %}
 {%- endmacro %}
 
+{% macro simple_pager(page, have_next, generator) -%}
+<div class="pagination">
+  <ul>
+      {% if page > 0 %}
+      <li>
+          <a href="{{ generator(page - 1) }}">&lt;</a>
+      </li>
+      {% else %}
+      <li class="disabled">
+          <a href="{{ generator(0) }}">&lt;</a>
+      </li>
+      {% endif %}
+      {% if have_next %}
+      <li>
+          <a href="{{ generator(page + 1) }}">&gt;</a>
+      </li>
+      {% else %}
+      <li class="disabled">
+          <a href="{{ generator(page) }}">&gt;</a>
+      </li>
+      {% endif %}
+  </ul>
+</div>
+{%- endmacro %}
+
 {# ---------------------- Forms -------------------------- #}
 {% macro render_field(form, field, kwargs={}, caller=None) %}
   {% set direct_error = h.is_field_error(field.errors) %}

flask_admin/templates/bootstrap2/admin/model/list.html

@@ -13,7 +13,7 @@
     {% block model_menu_bar %}
     <ul class="nav nav-tabs actions-nav">
         <li class="active">
-            <a href="javascript:void(0)">{{ _gettext('List') }} ({{ count }})</a>
+            <a href="javascript:void(0)">{{ _gettext('List') }}{% if count %} ({{ count }}){% endif %}</a>
         </li>
         {% if admin_view.can_create %}
         <li>
@@ -147,7 +147,13 @@
         </tr>
         {% endfor %}
     </table>
+    {% block list_pager %}
+    {% if num_pages is not none %}
     {{ lib.pager(page, num_pages, pager_url) }}
+    {% else %}
+    {{ lib.simple_pager(page, data|length == page_size, pager_url) }}
+    {% endif %}
+    {% endblock %}
     {% endblock %}
 
     {{ actionlib.form(actions, get_url('.action_view')) }}

flask_admin/templates/bootstrap3/admin/lib.html

@@ -74,6 +74,29 @@
 {% endif %}
 {%- endmacro %}
 
+{% macro simple_pager(page, have_next, generator) -%}
+<ul class="pagination">
+  {% if page > 0 %}
+  <li>
+      <a href="{{ generator(page - 1) }}">&lt;</a>
+  </li>
+  {% else %}
+  <li class="disabled">
+      <a href="{{ generator(0) }}">&lt;</a>
+  </li>
+  {% endif %}
+  {% if have_next %}
+  <li>
+      <a href="{{ generator(page + 1) }}">&gt;</a>
+  </li>
+  {% else %}
+  <li class="disabled">
+      <a href="{{ generator(page) }}">&gt;</a>
+  </li>
+  {% endif %}
+</ul>
+{%- endmacro %}
+
 {# ---------------------- Forms -------------------------- #}
 {% macro render_field(form, field, kwargs={}, caller=None) %}
   {% set direct_error = h.is_field_error(field.errors) %}

flask_admin/templates/bootstrap3/admin/model/list.html

@@ -13,7 +13,7 @@
     {% block model_menu_bar %}
     <ul class="nav nav-tabs actions-nav">
         <li class="active">
-            <a href="javascript:void(0)">{{ _gettext('List') }} ({{ count }})</a>
+            <a href="javascript:void(0)">{{ _gettext('List') }}{% if count %} ({{ count }}){% endif %}</a>
         </li>
         {% if admin_view.can_create %}
         <li>
@@ -146,7 +146,13 @@
         </tr>
         {% endfor %}
     </table>
+    {% block list_pager %}
+    {% if num_pages is not none %}
     {{ lib.pager(page, num_pages, pager_url) }}
+    {% else %}
+    {{ lib.simple_pager(page, data|length == page_size, pager_url) }}
+    {% endif %}
+    {% endblock %}
     {% endblock %}
 
     {{ actionlib.form(actions, get_url('.action_view')) }}

flask_admin/tests/mongoengine/test_basic.py

@@ -948,3 +948,20 @@ def test_form_args_embeddeddoc():
     eq_(form.timestamp.label.text, 'Last Updated Time')
     # This is the failure
     eq_(form.info.label.text, 'Information')
+
+
+def test_simple_list_pager():
+    app, db, admin = setup()
+    Model1, _ = create_models(db)
+
+    class TestModelView(CustomModelView):
+        simple_list_pager = True
+
+        def get_count_query(self):
+            assert False
+
+    view = TestModelView(Model1)
+    admin.add_view(view)
+
+    count, data = view.get_list(0, None, None, None, None)
+    ok_(count is None)

flask_admin/tests/sqla/test_basic.py

@@ -12,6 +12,7 @@ from . import setup
 
 from datetime import datetime, time, date
 
+
 class CustomModelView(ModelView):
     def __init__(self, model, session,
                  name=None, category=None, endpoint=None, url=None,
@@ -1680,3 +1681,21 @@ def test_safe_redirect():
     assert_true(rv.location.startswith('http://localhost/admin/model1/edit/'))
     assert_true('url=%2Fadmin%2Fmodel1%2F' in rv.location)
     assert_true('id=2' in rv.location)
+
+
+def test_simple_list_pager():
+    app, db, admin = setup()
+    Model1, _ = create_models(db)
+    db.create_all()
+
+    class TestModelView(CustomModelView):
+        simple_list_pager = True
+
+        def get_count_query(self):
+            assert False
+
+    view = TestModelView(Model1, db.session)
+    admin.add_view(view)
+
+    count, data = view.get_list(0, None, None, None, None)
+    assert_true(count is None)