Update a Firestore document containing an array field (async)

Update a Firestore document containing an array field (async).

Explore further

For detailed documentation that includes this code sample, see the following:

• Add and update data
• Add data to Cloud Firestore

Code sample

Python

To authenticate to Firestore, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

city_ref = db.collection("cities").document("DC")

# Atomically add a new region to the 'regions' array field.
await city_ref.update({"regions": firestore.ArrayUnion(["greater_virginia"])})

# // Atomically remove a region from the 'regions' array field.
await city_ref.update({"regions": firestore.ArrayRemove(["east_coast"])})

What's next

To search and filter code samples for other Google Cloud products, see the Google Cloud sample browser.