Less hacky sqlalchemy registration

Loosen versions in setup.py

README.rst

@@ -20,10 +20,10 @@ DB-API
 
 SQLAlchemy
 ----------
+First install this package to register it with SQLAlchemy (see ``setup.py``).
+
 .. code-block:: python
 
-    # This import has the side effect of registering with sqlalchemy
-    from pyhive import sqlalchemy_presto
     from sqlalchemy import *
     from sqlalchemy.engine import create_engine
     from sqlalchemy.schema import *

pyhive/sqlalchemy_hive.py

@@ -17,8 +17,6 @@
 from sqlalchemy.sql import compiler
 import decimal
 import re
-import sqlalchemy
-import sys
 import warnings
 
 try:
@@ -49,13 +47,6 @@ def process_result_value(self, value, dialect):
         return decimal.Decimal(value)
 
 
-def register_in_sqlalchemy():
-    # Register us under SQLAlchemy
-    sys.modules['sqlalchemy.databases.hive'] = sys.modules[__name__]
-    sqlalchemy.databases.hive = sys.modules[__name__]
-register_in_sqlalchemy()
-
-
 class HiveIdentifierPreparer(compiler.IdentifierPreparer):
     # https://github.com/apache/hive/blob/trunk/ql/src/java/org/apache/hadoop/hive/ql/parse/HiveLexer.g
     reserved_words = frozenset([
@@ -361,7 +352,7 @@ def reflecttable(self, connection, table, include_columns=None):
         try:
             # This needs the table name to be unescaped (no backticks).
             rows = connection.execute('DESCRIBE {}'.format(table)).fetchall()
-        except sqlalchemy.exc.OperationalError as e:
+        except exc.OperationalError as e:
             # Does the table exist?
             regex_fmt = r'TExecuteStatementResp.*SemanticException.*Table not found {}'
             regex = regex_fmt.format(re.escape(table.name))
@@ -401,5 +392,3 @@ def reflecttable(self, connection, table, include_columns=None):
     def do_rollback(self, dbapi_connection):
         # No transactions for Hive
         pass
-
-dialect = HiveDialect

pyhive/sqlalchemy_presto.py

@@ -16,18 +16,9 @@
 from sqlalchemy.engine import default
 from sqlalchemy.sql import compiler
 import re
-import sqlalchemy
-import sys
 import warnings
 
 
-def register_in_sqlalchemy():
-    # Register us under SQLAlchemy
-    sys.modules['sqlalchemy.databases.presto'] = sys.modules[__name__]
-    sqlalchemy.databases.presto = sys.modules[__name__]
-register_in_sqlalchemy()
-
-
 class PrestoIdentifierPreparer(compiler.IdentifierPreparer):
     # https://github.com/facebook/presto/blob/master/presto-parser/src/main/antlr3/com/facebook/presto/sql/parser/Statement.g
     reserved_words = frozenset([
@@ -181,5 +172,3 @@ def reflecttable(self, connection, table, include_columns=None):
     def do_rollback(self, dbapi_connection):
         # No transactions for Presto
         pass
-
-dialect = PrestoDialect

pyhive/tests/test_sqlalchemy_hive.py

@@ -7,8 +7,6 @@
 from sqlalchemy.types import String
 import datetime
 import decimal
-# This import has the side effect of registering with sqlalchemy
-import pyhive.sqlalchemy_hive
 
 
 class TestSqlAlchemyHive(SqlAlchemyTestCase):

pyhive/tests/test_sqlalchemy_presto.py

@@ -6,8 +6,6 @@
 from sqlalchemy.schema import Table
 from sqlalchemy.types import String
 import contextlib
-# This import has the side effect of registering with sqlalchemy
-import pyhive.sqlalchemy_presto
 
 
 class TestSqlAlchemyPresto(SqlAlchemyTestCase):

setup.py

@@ -19,20 +19,32 @@
         "Topic :: Database",
     ],
     extras_require={
-        "Presto": ['requests'],
-        "Hive": ['sasl>=0.1.3', 'thrift>=0.9.1'],
-        "SQLAlchemy": ['sqlalchemy==0.5.8'],
+        "Presto": ['requests>=1.0.0'],
+        "Hive": ['sasl>=0.1.3', 'thrift>=0.8.0'],
+        "SQLAlchemy": ['sqlalchemy>=0.5.0'],
     },
     test_suite='nose.collector',
     tests_require=[
-        'mock',
+        'mock>=1.0.0',
         'nose',
-        'requests',
+        'requests>=1.0.0',
         'sasl>=0.1.3',
-        'sqlalchemy==0.5.8',
-        'thrift>=0.9.1',
+        'sqlalchemy>=0.5.0',
+        'thrift>=0.8.0',
     ],
     package_data={
         '': ['*.rst'],
     },
+    entry_points={
+        # New versions
+        'sqlalchemy.dialects': [
+            'hive = pyhive.sqlalchemy_hive:HiveDialect',
+            'presto = pyhive.sqlalchemy_presto:PrestoDialect',
+        ],
+        # Version 0.5
+        'sqlalchemy.databases': [
+            'hive = pyhive.sqlalchemy_hive:HiveDialect',
+            'presto = pyhive.sqlalchemy_presto:PrestoDialect',
+        ],
+    }
 )