CoroWrapper AsyncPostgresqlConnection.release_cursor ... was never yi…

…elded from (#86)

* scalar function: cursor.release in finally clause
* peewee <= 2.10.2
* release cursor after COMMIT, BEGIN, ROLLBACK and other
* remove duplicate import of logging
* aiopg is not compatible now with python 3.7 (syntax error)

.travis.yml

@@ -6,7 +6,9 @@ python:
   - "3.4"
   - "3.5"
   - "3.6"
-  - "nightly" # currently points to 3.7-dev
+  # TODO: aiopg is not compatible now with python 3.7 (syntax error)
+  # Uncomment line bellow when issue fixed: https://github.com/aio-libs/aiopg/issues/436
+  # - "nightly" # currently points to 3.7-dev
 addons:
   postgresql: "9.3"
 services:

peewee_async.py

@@ -14,7 +14,6 @@
 
 """
 import asyncio
-import logging
 import uuid
 import contextlib
 import peewee
@@ -585,7 +584,6 @@ def select(query):
     finally:
         yield from cursor.release
 
-    yield from cursor.release
     return result
 
 
@@ -674,9 +672,12 @@ def scalar(query, as_tuple=False):
     :return: result is the same as after sync ``query.scalar()`` call
     """
     cursor = yield from _execute_query_async(query)
-    row = yield from cursor.fetchone()
 
-    yield from cursor.release
+    try:
+        row = yield from cursor.fetchone()
+    finally:
+        yield from cursor.release
+
     if row and not as_tuple:
         return row[0]
     else:
@@ -1419,23 +1420,23 @@ def __init__(self, db):
 
     @asyncio.coroutine
     def commit(self, begin=True):
-        yield from _run_sql(self.db, 'COMMIT')
+        yield from _run_no_result_sql(self.db, 'COMMIT')
         if begin:
-            yield from _run_sql(self.db, 'BEGIN')
+            yield from _run_no_result_sql(self.db, 'BEGIN')
 
     @asyncio.coroutine
     def rollback(self, begin=True):
-        yield from _run_sql(self.db, 'ROLLBACK')
+        yield from _run_no_result_sql(self.db, 'ROLLBACK')
         if begin:
-            yield from _run_sql(self.db, 'BEGIN')
+            yield from _run_no_result_sql(self.db, 'BEGIN')
 
     @asyncio.coroutine
     def __aenter__(self):
         if not asyncio.Task.current_task(loop=self.loop):
             raise RuntimeError("The transaction must run within a task")
         yield from self.db.push_transaction_async()
         if self.db.transaction_depth_async() == 1:
-            yield from _run_sql(self.db, 'BEGIN')
+            yield from _run_no_result_sql(self.db, 'BEGIN')
         return self
 
     @asyncio.coroutine
@@ -1464,15 +1465,15 @@ def __init__(self, db, sid=None):
 
     @asyncio.coroutine
     def commit(self):
-        yield from _run_sql(self.db, 'RELEASE SAVEPOINT %s;' % self.quoted_sid)
+        yield from _run_no_result_sql(self.db, 'RELEASE SAVEPOINT %s;' % self.quoted_sid)
 
     @asyncio.coroutine
     def rollback(self):
-        yield from _run_sql(self.db, 'ROLLBACK TO SAVEPOINT %s;' % self.quoted_sid)
+        yield from _run_no_result_sql(self.db, 'ROLLBACK TO SAVEPOINT %s;' % self.quoted_sid)
 
     @asyncio.coroutine
     def __aenter__(self):
-        yield from _run_sql(self.db, 'SAVEPOINT %s;' % self.quoted_sid)
+        yield from _run_no_result_sql(self.db, 'SAVEPOINT %s;' % self.quoted_sid)
         return self
 
     @asyncio.coroutine
@@ -1542,6 +1543,12 @@ def _run_sql(database, operation, *args, **kwargs):
         return cursor
 
 
+@asyncio.coroutine
+def _run_no_result_sql(database, operation, *args, **kwargs):
+    cursor = yield from _run_sql(database, operation, *args, **kwargs)
+    yield from cursor.release
+
+
 @asyncio.coroutine
 def _execute_query_async(query):
     """Execute query and return cursor object.

setup.py

@@ -41,7 +41,7 @@
     license='MIT',
     zip_safe=False,
     install_requires=(
-        'peewee >= 2.8.0',
+        'peewee>=2.8.0,<=2.10.2',
     ),
     py_modules=[
         'peewee_async',