From 3999f42e5a2ca91dc86fe4cc7c03f923fa8849cd Mon Sep 17 00:00:00 2001
From: Benjamin Dauvergne <bdauvergne@entrouvert.com>
Date: Fri, 29 Nov 2019 15:27:22 +0100
Subject: [PATCH 06/13] engine: cache EngineDimension.members (#38067)

---
 bijoe/engine.py  | 22 +++++++++++++++++++++-
 bijoe/schemas.py |  5 ++++-
 bijoe/utils.py   |  1 +
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/bijoe/engine.py b/bijoe/engine.py
index 765f5ee..a8a7b89 100644
--- a/bijoe/engine.py
+++ b/bijoe/engine.py
@@ -17,10 +17,12 @@
 import contextlib
 import logging
 import itertools
+import hashlib
 
 import collections
 import psycopg2
 
+from django.core.cache import cache
 
 from . import schemas
 
@@ -61,9 +63,20 @@ class EngineDimension(object):
     def __getattr__(self, name):
         return getattr(self.dimension, name)
 
+    @property
+    def cache_key(self):
+        return hashlib.md5(self.engine.path + self.engine_cube.name + self.name).hexdigest()
+
     @property
     def members(self):
         assert self.type != 'date'
+
+        members = cache.get(self.cache_key)
+        if members is not None:
+            return members
+
+        members = []
+
         value = self.value
         value_label = self.value_label or value
         order_by = self.order_by
@@ -96,7 +109,9 @@ class EngineDimension(object):
             for row in cursor.fetchall():
                 if row[0] is None:
                     continue
-                yield Member(*row)
+                members.append(Member(*row))
+        cache.set(self.cache_key, members, 600)
+        return members
 
 
 class SchemaJSONDimension(schemas.Dimension):
@@ -132,6 +147,11 @@ class EngineJSONDimension(EngineDimension):
         self.engine_cube = engine_cube
         self.dimension = SchemaJSONDimension(self.engine_cube.json_field, name)
 
+    @property
+    def cache_key(self):
+        return hashlib.md5(self.engine.path + self.engine_cube.json_field
+                           + self.engine_cube.name + self.name).hexdigest()
+
     def to_json(self):
         return {
             'name': self.name,
diff --git a/bijoe/schemas.py b/bijoe/schemas.py
index 856f0ab..1705384 100644
--- a/bijoe/schemas.py
+++ b/bijoe/schemas.py
@@ -379,7 +379,7 @@ class Cube(Base):
 
 
 class Warehouse(Base):
-    __slots__ = ['name', 'label', 'pg_dsn', 'search_path', 'cubes']
+    __slots__ = ['name', 'label', 'pg_dsn', 'search_path', 'cubes', 'path']
     __types__ = {
         'name': str,
         'label': unicode,
@@ -387,8 +387,11 @@ class Warehouse(Base):
         'search_path': [str],
         'cubes': [Cube],
         'search_path': [str],
+        'path': str,
     }
 
+    path = None
+
     def check(self):
         names = collections.Counter(cube.name for cube in self.cubes)
         duplicates = [k for k, v in names.iteritems() if v > 1]
diff --git a/bijoe/utils.py b/bijoe/utils.py
index 4fb18e3..a4afa53 100644
--- a/bijoe/utils.py
+++ b/bijoe/utils.py
@@ -45,6 +45,7 @@ def get_warehouses_by_paths(paths):
     warehouses = []
     for path in paths:
         d = json.load(open(path))
+        d['path'] = path
         warehouses.append(Warehouse.from_json(d))
     return warehouses
 
-- 
2.23.0