Cosmos DB Bindings for Azure Functions
Azure Functions provides robust integration with Azure Cosmos DB, a globally distributed, multi-model database service. These integrations are primarily achieved through input and output bindings, allowing you to easily read from and write to Cosmos DB containers within your serverless functions.
This documentation covers how to configure and use Cosmos DB bindings in your Azure Functions projects.
Key Benefits:
- Simplified Data Access: Reduce boilerplate code for database operations.
- Declarative Configuration: Define data interactions directly in your function's configuration.
- Event-Driven Scenarios: Trigger functions based on changes in Cosmos DB using the Cosmos DB trigger.
- Scalability: Leverage the power of Cosmos DB's global distribution and scalability.
Microsoft.Azure.WebJobs.Extensions.CosmosDB NuGet package installed in your function app project.
Supported Operations:
- Reading documents: Retrieve single documents or collections of documents.
- Writing documents: Insert or update documents in a container.
- Deleting documents: Remove documents from a container.
- Cosmos DB Triggers: Execute a function in response to changes in a Cosmos DB container.
Configuration:
Cosmos DB bindings are configured in your function.json file (for JavaScript, Python, PowerShell, etc.) or through attributes in your code (for C#, Java, TypeScript).
A connection string to your Cosmos DB account is typically provided via an application setting in your Azure Function App's configuration, referenced by a name like CosmosDbConnectionString.
Example Connection String Setting:
{
"IsEncrypted": false,
"Values": {
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"CosmosDbConnectionString": "AccountEndpoint=https://mycosmosdb.documents.azure.com:443/;AccountKey=mysecretkey;"
}
}