How to use SQLAlchemy ORM to access HubDB 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 HubDB and the SQLAlchemy toolkit, you can build HubDB-connected Python applications and scripts. This article shows how to use SQLAlchemy to connect to HubDB data to query, update, delete, and insert HubDB data.

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

Connecting to HubDB Data

Connecting to HubDB 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.

There are two authentication methods available for connecting to HubDB data source: OAuth Authentication with a public HubSpot application and authentication with a Private application token.

Using a Custom OAuth App

AuthScheme must be set to "OAuth" in all OAuth flows. Be sure to review the Help documentation for the required connection properties for you specific authentication needs (desktop applications, web applications, and headless machines).

Follow the steps below to register an application and obtain the OAuth client credentials:

1. Log into your HubSpot app developer account.
   • Note that it must be an app developer account. Standard HubSpot accounts cannot create public apps.
2. On the developer account home page, click the Apps tab.
3. Click Create app.
4. On the App info tab, enter and optionally modify values that are displayed to users when they connect. These values include the public application name, application logo, and a description of the application.
5. On the Auth tab, supply a callback URL in the "Redirect URLs" box.
   • If you're creating a desktop application, set this to a locally accessible URL like http://localhost:33333.
   • If you are creating a Web application, set this to a trusted URL where you want users to be redirected to when they authorize your application.
6. Click Create App. HubSpot then generates the application, along with its associated credentials.
7. On the Auth tab, note the Client ID and Client secret. You will use these later to configure the driver.

8. Under Scopes, select any scopes you need for your application's intended functionality.

   A minimum of the following scopes is required to access tables:

   • hubdb
   • oauth
   • crm.objects.owners.read
9. Click Save changes.
10. Install the application into a production portal with access to the features that are required by the integration.
    • Under "Install URL (OAuth)", click Copy full URL to copy the installation URL for your application.
    • Navigate to the copied link in your browser. Select a standard account in which to install the application.
    • Click Connect app. You can close the resulting tab.

Using a Private App

To connect using a HubSpot private application token, set the AuthScheme property to "PrivateApp."

You can generate a private application token by following the steps below:

1. In your HubDB account, click the settings icon (the gear) in the main navigation bar.
2. In the left sidebar menu, navigate to Integrations > Private Apps.
3. Click Create private app.
4. On the Basic Info tab, configure the details of your application (name, logo, and description).
5. On the Scopes tab, select Read or Write for each scope you want your private application to be able to access.
6. A minimum of hubdb and crm.objects.owners.read is required to access tables.
7. After you are done configuring your application, click Create app in the top right.
8. Review the info about your application's access token, click Continue creating, and then Show token.
9. Click Copy to copy the private application token.

To connect, set PrivateAppToken to the private application token you retrieved.

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

Install Required Modules

Use the pip utility to install the SQLAlchemy toolkit and SQLAlchemy ORM package:

pip install sqlalchemy
pip install sqlalchemy.orm

Be sure to import the appropriate modules:

from sqlalchemy import create_engine, String, Column
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

Model HubDB Data in Python

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

NOTE: Users should URL encode the any connection string properties that include special characters. For more information, refer to the SQL Alchemy documentation.

engine = create_engine("hubdb:///?AuthScheme=OAuth&OAuthClientID=MyOAuthClientID&OAuthClientSecret=MyOAuthClientSecret&CallbackURL=http://localhost:33333&InitiateOAuth=GETANDREFRESH")

Declare a Mapping Class for HubDB 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 NorthwindProducts 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 NorthwindProducts(base):
	__tablename__ = "NorthwindProducts"
	PartitionKey = Column(String,primary_key=True)
	Name = Column(String)
	...

Query HubDB 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("hubdb:///?AuthScheme=OAuth&OAuthClientID=MyOAuthClientID&OAuthClientSecret=MyOAuthClientSecret&CallbackURL=http://localhost:33333&InitiateOAuth=GETANDREFRESH")
factory = sessionmaker(bind=engine)
session = factory()
for instance in session.query(NorthwindProducts).filter_by(Id="1"):
	print("PartitionKey: ", instance.PartitionKey)
	print("Name: ", instance.Name)
	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

NorthwindProducts_table = NorthwindProducts.metadata.tables["NorthwindProducts"]
for instance in session.execute(NorthwindProducts_table.select().where(NorthwindProducts_table.c.Id == "1")):
	print("PartitionKey: ", instance.PartitionKey)
	print("Name: ", instance.Name)
	print("---------")

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

Insert HubDB Data

To insert HubDB data, define an instance of the mapped class and add it to the active session. Call the commit function on the session to push all added instances to HubDB.

new_rec = NorthwindProducts(PartitionKey="placeholder", Id="1")
session.add(new_rec)
session.commit()

Update HubDB Data

To update HubDB data, fetch the desired record(s) with a filter query. Then, modify the values of the fields and call the commit function on the session to push the modified record to HubDB.

updated_rec = session.query(NorthwindProducts).filter_by(SOME_ID_COLUMN="SOME_ID_VALUE").first()
updated_rec.Id = "1"
session.commit()

Delete HubDB Data

To delete HubDB data, fetch the desired record(s) with a filter query. Then delete the record with the active session and call the commit function on the session to perform the delete operation on the provided records (rows).

deleted_rec = session.query(NorthwindProducts).filter_by(SOME_ID_COLUMN="SOME_ID_VALUE").first()
session.delete(deleted_rec)
session.commit()

Free Trial & More Information

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