Add geography support to snowflake-sqlalchemy (#271)

Author: Dormira

__init__.py

@@ -43,6 +43,7 @@
     DEC,
     DOUBLE,
     FIXED,
+    GEOGRAPHY,
     NUMBER,
     OBJECT,
     STRING,
@@ -87,6 +88,7 @@
     'DEC',
     'DOUBLE',
     'FIXED',
+    'GEOGRAPHY',
     'OBJECT',
     'NUMBER',
     'STRING',

base.py

@@ -505,6 +505,8 @@ def visit_TIMESTAMP_LTZ(self, type_, **kw):
     def visit_TIMESTAMP(self, type_, **kw):
         return "TIMESTAMP"
 
+    def visit_GEOGRAPHY(self, type_, **kw):
+        return "GEOGRAPHY"
 
 construct_arguments = [
     (Table, {

custom_types.py

@@ -47,3 +47,6 @@ class TIMESTAMP_LTZ(SnowflakeType):
 
 class TIMESTAMP_NTZ(SnowflakeType):
     __visit_name__ = 'TIMESTAMP_NTZ'
+
+class GEOGRAPHY(SnowflakeType):
+    __visit_name__ = 'GEOGRAPHY'

snowdialect.py

@@ -44,7 +44,7 @@
     SnowflakeIdentifierPreparer,
     SnowflakeTypeCompiler,
 )
-from .custom_types import ARRAY, OBJECT, TIMESTAMP_LTZ, TIMESTAMP_NTZ, TIMESTAMP_TZ, VARIANT
+from .custom_types import ARRAY, OBJECT, TIMESTAMP_LTZ, TIMESTAMP_NTZ, TIMESTAMP_TZ, VARIANT, GEOGRAPHY
 
 colspecs = {}
 
@@ -82,6 +82,7 @@
     'VARIANT': VARIANT,
     'OBJECT': OBJECT,
     'ARRAY': ARRAY,
+    'GEOGRAPHY': GEOGRAPHY,
 }
 
 

test/test_custom_types.py

@@ -10,6 +10,7 @@ def test_string_conversions():
         'TIMESTAMP_TZ',
         'TIMESTAMP_LTZ',
         'TIMESTAMP_NTZ',
+        'GEOGRAPHY',
     ]
     sf_types = [
         'TEXT',

test/test_geography.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+from parameters import CONNECTION_PARAMETERS
+from snowflake.sqlalchemy import GEOGRAPHY
+from sqlalchemy import Column, Integer, MetaData, Table
+from sqlalchemy.sql import select
+from json import loads
+
+def test_create_table_geography_datatypes(engine_testaccount):
+    """
+    Create table including geography data types
+    """
+
+    metadata = MetaData()
+    table_name = "test_geography0"
+    test_geography = Table(
+        table_name,
+        metadata,
+        Column('id', Integer, primary_key=True),
+        Column('geo', GEOGRAPHY),
+        )
+    metadata.create_all(engine_testaccount)
+    try:
+        assert test_geography is not None
+    finally:
+        test_geography.drop(engine_testaccount)
+
+def test_inspect_geography_datatypes(engine_testaccount):
+    """
+    Create table including geography data types
+    """
+    metadata = MetaData()
+    table_name = "test_geography0"
+    test_geography = Table(
+        table_name,
+        metadata,
+        Column('id', Integer, primary_key=True),
+        Column('geo1', GEOGRAPHY),
+        Column('geo2', GEOGRAPHY))
+    metadata.create_all(engine_testaccount)
+
+    try:
+        test_point = 'POINT(-122.35 37.55)'
+        test_point1 = '{"coordinates": [-122.35,37.55],"type": "Point"}'
+
+        ins = test_geography.insert().values(
+            id=1,
+            geo1=test_point,
+            geo2=test_point1
+        )
+
+        results = engine_testaccount.execute(ins)
+        results.close()
+
+        # select
+        conn = engine_testaccount.connect()
+        s = select([test_geography])
+        results = conn.execute(s)
+        rows = results.fetchone()
+        results.close()
+        assert rows[0] == 1
+        assert rows[1] == rows[2]
+        assert loads(rows[2]) == loads(test_point1)
+    finally:
+        test_geography.drop(engine_testaccount)
+