Use SQLAlchemy ORMs to Access Wasabi Data in Python

The rich ecosystem of Python modules lets you get to work quickly and integrate your systems effectively. With the CData Python Connector for Wasabi and the SQLAlchemy toolkit, you can build Wasabi-connected Python applications and scripts. This article shows how to use SQLAlchemy to connect to Wasabi data to query Wasabi data.

With built-in optimized data processing, the CData Python Connector offers unmatched performance for interacting with live Wasabi data in Python. When you issue complex SQL queries from Wasabi, the CData Connector pushes supported SQL operations, like filters and aggregations, directly to Wasabi and utilizes the embedded SQL engine to process unsupported operations client-side (often SQL functions and JOIN operations).

Connecting to Wasabi Data

Connecting to Wasabi data looks just like connecting to any relational data source. Create a connection string using the required connection properties. For this article, you will pass the connection string as a parameter to the create_engine function.

To authorize Wasabi requests, provide the credentials for an administrator account or for an IAM user with custom permissions. Set AccessKey to the access key Id. Set SecretKey to the secret access key.

Note: You can connect as the AWS account administrator, but it is recommended to use IAM user credentials to access AWS services.

For information on obtaining the credentials and other authentication methods, refer to the Getting Started section of the Help documentation.

Follow the procedure below to install SQLAlchemy and start accessing Wasabi through Python objects.

Install Required Modules

Use the pip utility to install the SQLAlchemy toolkit:

pip install sqlalchemy

Be sure to import the module with the following:

import sqlalchemy

Model Wasabi Data in Python

You can now connect with a connection string. Use the create_engine function to create an Engine for working with Wasabi data.

engine = create_engine("wasabi:///?AccessKey=a123&SecretKey=s123")

Declare a Mapping Class for Wasabi Data

After establishing the connection, declare a mapping class for the table you wish to model in the ORM (in this article, we will model the Buckets table). Use the sqlalchemy.ext.declarative.declarative_base function and create a new class with some or all of the fields (columns) defined.

base = declarative_base()
class Buckets(base):
	__tablename__ = "Buckets"
	Name = Column(String,primary_key=True)
	OwnerId = Column(String)
	...

Query Wasabi Data

With the mapping class prepared, you can use a session object to query the data source. After binding the Engine to the session, provide the mapping class to the session query method.

Using the query Method

engine = create_engine("wasabi:///?AccessKey=a123&SecretKey=s123")
factory = sessionmaker(bind=engine)
session = factory()
for instance in session.query(Buckets).filter_by(Name="TestBucket"):
	print("Name: ", instance.Name)
	print("OwnerId: ", instance.OwnerId)
	print("---------")

Alternatively, you can use the execute method with the appropriate table object. The code below works with an active session.

Using the execute Method

Buckets_table = Buckets.metadata.tables["Buckets"]
for instance in session.execute(Buckets_table.select().where(Buckets_table.c.Name == "TestBucket")):
	print("Name: ", instance.Name)
	print("OwnerId: ", instance.OwnerId)
	print("---------")

For examples of more complex querying, including JOINs, aggregations, limits, and more, refer to the Help documentation for the extension.

Free Trial & More Information

Download a free, 30-day trial of the Wasabi Python Connector to start building Python apps and scripts with connectivity to Wasabi data. Reach out to our Support Team if you have any questions.