Add improved OBJECT

src/snowflake/sqlalchemy/base.py

@@ -9,7 +9,7 @@
 from sqlalchemy.engine import default
 from sqlalchemy.schema import Sequence, Table
 from sqlalchemy.sql import compiler, expression
-from sqlalchemy.sql.elements import quoted_name
+from sqlalchemy.sql.elements import BinaryExpression, quoted_name
 from sqlalchemy.util.compat import string_types
 
 from .custom_commands import AWSBucket, AzureContainer, ExternalStage
@@ -153,6 +153,10 @@ class SnowflakeCompiler(compiler.SQLCompiler):
     def visit_sequence(self, sequence, **kw):
         return self.dialect.identifier_preparer.format_sequence(sequence) + ".nextval"
 
+    def visit_json_getitem_op_binary(self, a: BinaryExpression, b, **kw):
+        """Render keys selected from OBJECTs."""
+        return self.process(a.left, **kw) + "[" + self.process(a.right, **kw) + "]"
+
     def visit_merge_into(self, merge_into, **kw):
         clauses = " ".join(
             clause._compiler_dispatch(self, **kw) for clause in merge_into.clauses

src/snowflake/sqlalchemy/custom_types.py

@@ -3,10 +3,13 @@
 #
 import datetime
 import decimal
+import json
 import re
 
 import sqlalchemy.types as sqltypes
 import sqlalchemy.util as util
+from sqlalchemy import sql
+from sqlalchemy.sql import expression
 
 TEXT = sqltypes.VARCHAR
 CHARACTER = sqltypes.CHAR
@@ -40,8 +43,43 @@ class VARIANT(SnowflakeType):
     __visit_name__ = "VARIANT"
 
 
-class OBJECT(SnowflakeType):
+class OBJECT(sqltypes.Indexable, SnowflakeType):
     __visit_name__ = "OBJECT"
+    comparator_factory = sqltypes.JSON.Comparator
+
+    def bind_expression(self, bindvalue: expression.BindParameter):
+        """Build the SQL string compoenent when inserted into a statement.
+
+        The OBJECT must be sent as a string and passed to the `parse_json` Snowflake
+        function when INSERTing or UPDATE-ing.
+        """
+        return sql.func.parse_json(bindvalue)
+
+    def bind_processor(self, dialect):
+        def process(value):
+            """Process data before sending to connector as the value to bind."""
+            if value is not None:
+                value = json.dumps(value)
+
+            return value
+
+        return process
+
+    def literal_processor(self, dialect):
+        def process(value) -> str:
+            """Process data when binding literal string directly into statement."""
+            return f"'{self.bind_processor(dialect)(value)}'"
+
+        return process
+
+    def result_processor(self, dialect, coltype):
+        def process(value):
+            """Process the value recieved from the connector."""
+            if value is not None:
+                value = json.loads(value)
+            return value
+
+        return process
 
 
 class ARRAY(SnowflakeType):