TST BUG: We still need OperationalError import

tests/util.py

@@ -1,18 +1,9 @@
 import io
 import os.path
 from six.moves.urllib.request import urlopen
-from sqlalchemy import create_engine
 
 from geopandas import GeoDataFrame, GeoSeries
 
-try:
-    from pandas import read_sql_table
-except ImportError:
-    PANDAS_NEW_SQL_API = False
-else:
-    PANDAS_NEW_SQL_API = True
-
-
 # Compatibility layer for Python 2.6: try loading unittest2
 import sys
 if sys.version_info[:2] == (2, 6):
@@ -24,6 +15,20 @@ if sys.version_info[:2] == (2, 6):
 else:
     import unittest
 
+try:
+    import psycopg2
+    from psycopg2 import OperationalError
+except ImportError:
+    class OperationalError(Exception):
+        pass
+
+try:
+    from pandas import read_sql_table
+except ImportError:
+    PANDAS_NEW_SQL_API = False
+else:
+    PANDAS_NEW_SQL_API = True
+
 
 def download_nybb():
     """ Returns the path to the NYC boroughs file. Downloads if necessary. """
@@ -52,17 +57,12 @@ def validate_boro_df(test, df):
 
 def connect(dbname):
     try:
-        if PANDAS_NEW_SQL_API:
-            driver = 'psycopg2'
-            conn_str = 'postgresql+{driver}://localhost/{dbname}'
-            engine = create_engine(conn_str.format(driver=driver, dbname=dbname))
-            return engine
-        else:
-            con = psycopg2.connect(dbname=dbname)
-            return con
+        con = psycopg2.connect(dbname=dbname)
     except (NameError, OperationalError):
         return None
 
+    return con
+
 
 def create_db(df):
     """
@@ -77,22 +77,13 @@ def create_db(df):
     # 'test_geopandas' and enable postgis in it:
     # > createdb test_geopandas
     # > psql -c "CREATE EXTENSION postgis" -d test_geopandas
-    try:
-        con = connect('test_geopandas')
-    except:
-        return False
+    con = connect('test_geopandas')
     if con is None:
         return False
-    if PANDAS_NEW_SQL_API:
-        try:
-            con = con.connect()
-        except:
-            return False
-    else:
-        con = con.cursor()
 
     try:
-        con.execute("DROP TABLE IF EXISTS nybb;")
+        cursor = con.cursor()
+        cursor.execute("DROP TABLE IF EXISTS nybb;")
 
         sql = """CREATE TABLE nybb (
             geom        geometry,
@@ -101,18 +92,20 @@ def create_db(df):
             shape_leng  float,
             shape_area  float
         );"""
-        con.execute(sql)
+        cursor.execute(sql)
 
         for i, row in df.iterrows():
             sql = """INSERT INTO nybb VALUES (
                 ST_GeometryFromText(%s), %s, %s, %s, %s
             );"""
-            con.execute(sql, (row['geometry'].wkt,
+            cursor.execute(sql, (row['geometry'].wkt,
                                  row['BoroCode'],
                                  row['BoroName'],
                                  row['Shape_Leng'],
                                  row['Shape_Area']))
     finally:
+        cursor.close()
+        con.commit()
         con.close()
 
     return True