Azure Functions Extensions Bindings Cosmos DB library for Python

This library allows Cosmos DB Input bindings in Python Function Apps to recognize and bind to client types from the Azure Cosmos DB SDK.

Cosmos DB client types can be generated from:

• Cosmos DB Input

Source code Package (PyPi) | Samples

Getting started

Prerequisites

• Python 3.9 or later is required to use this package. For more details, please read our page on Python Functions version support policy.

• You must have an Azure subscription and an Azure storage account to use this package.

Install the package

Install the Azure Functions Extensions Bindings Cosmos DB library for Python with pip:

pip install azurefunctions-extensions-bindings-cosmosdb

Create a storage account

If you wish to create a new storage account, you can use the Azure Portal, Azure PowerShell, or Azure CLI:

# Create a new resource group to hold the storage account -
# if using an existing resource group, skip this step
az group create --name my-resource-group --location westus2

# Create the storage account
az storage account create -n my-storage-account-name -g my-resource-group

Bind to the SDK-type

The Azure Functions Extensions Bindings Cosmos DB library for Python allows you to create a function app with Cosmos DB Input and define the type as a CosmosClient, DatabaseProxy, or ContainerProxy. Instead of receiving a DocumentList, when the function is executed, the type returned will be the defined SDK-type and have all of the properties and methods available as seen in the Azure Storage Cosmos DB library for Python.

import logging
import azure.functions as func
import azurefunctions.extensions.bindings.cosmosdb as cosmos

app = func.FunctionApp(http_auth_level=func.AuthLevel.FUNCTION)

@app.route(route="cosmos")
@app.cosmos_db_input(arg_name="container",
                     connection="CosmosDBConnection",
                     database_name="db_name",
                     container_name="container_name")
def get_docs(req: func.HttpRequest, client: cosmos.CosmosClient):
    databases = client.list_databases()
    for db in databases:
        logging.info(f"Found database with ID: {db.get('id')}")

    return "ok"

Troubleshooting

General

The SDK-types raise exceptions defined in Azure Core.

This list can be used for reference to catch thrown exceptions. To get the specific error code of the exception, use the error_code attribute, i.e, exception.error_code.

Next steps

More sample code

Get started with our Cosmos DB samples.

Several samples are available in this GitHub repository. These samples provide example code for additional scenarios commonly encountered while working with Cosmos DB:

• cosmosdb_samples_cosmosclient - Examples for using the CosmosClient type:

  • From CosmosDBInput

• cosmosdb_samples_databaseproxy - Examples for using the DatabaseProxy type:

  • From CosmosDBInput

• cosmosdb_samples_containerclient - Examples for using the ContainerProxy type:

  • From CosmosDBInput

Additional documentation

For more information on the Azure Cosmos DB SDK, see the Azure Cosmos DB documentation on learn.microsoft.com and the Azure Cosmos DB README.

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.