Merge pull request #60 from fenngwd/fix/flask

fix(flask): construct a proxy to connection

peeweext/__init__.py

@@ -1 +1 @@
-__version__ = '1.2.4'
+__version__ = '1.2.5'

peeweext/flask.py

@@ -3,20 +3,32 @@
 from playhouse import db_url
 
 
+class UninitializedException(Exception):
+    pass
+
+
 class Peeweext:
     def __init__(self, ns='PW_'):
         self.ns = ns
+        self._database = None
+        # make a connection pool proxy
+        self.database = LocalProxy(self._get_db)
 
     def init_app(self, app):
         config = app.config.get_namespace(self.ns)
         self.model_class = import_string(
             config.get('model', 'peeweext.model.Model'))
         conn_params = config.get('conn_params', {})
-        self.database = db_url.connect(config['db_url'], **conn_params)
+
+        # initialize private connection pool
+        self._database = db_url.connect(config['db_url'], **conn_params)
+
         self._register_handlers(app)
 
     def _get_db(self):
-        return self.database
+        if not self._database:
+            raise UninitializedException()
+        return self._database
 
     @cached_property
     def Model(self):

tests/test_flask.py

@@ -1,6 +1,9 @@
 import peewee
+import pytest
 from flask import Flask
 
+import peeweext.flask
+from peeweext.flask import Peeweext
 from .flaskapp import app, pwmysql, PW_MYSQL_DB_URL
 
 
@@ -37,3 +40,29 @@ def test_flask_init_app_duplicate():
         assert pwmysql.database.is_closed()
     finally:
         Comment.drop_table()
+
+
+__inner_db = pwmysql._database
+_db = pwmysql.database
+
+
+def test_flask_module_load_not_cache_pool():
+    app1 = Flask("other app")
+    app1.config.setdefault("PW_MYSQL_DB_URL", PW_MYSQL_DB_URL)
+
+    # init_app to other app will update instance's database connection pool
+    pwmysql.init_app(app1)
+
+    # after init_app again, inner connection pool will change
+    assert pwmysql._database != __inner_db
+
+    # after init_app again, pub connection pool won't change
+    assert pwmysql.database == _db
+
+    # test before/after request works fine
+    assert pwmysql.database.is_closed()
+
+    pwu = Peeweext(ns='PW_MYSQL_')
+
+    with pytest.raises(peeweext.flask.UninitializedException) as e:
+        pwu.database.execute_sql("select 1")