Update a Firestore document containing an array field (async)

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

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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"])})

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