Interact with Azure Cosmos DB using Rust

Azure Cosmos DB SDK for Rust is a client library for Azure Cosmos DB's NoSQL API, a globally distributed, multi-model database. It has a three-level client hierarchy: a CosmosClient for account-level operations (created directly from the account endpoint), a DatabaseClient for database operations (obtained via client.database_client()), and a ContainerClient for container/item operations (obtained via database.container_client()). Configuration is read from COSMOS_ENDPOINT, COSMOS_DATABASE, and COSMOS_CONTAINER environment variables, and it authenticates with DeveloperToolsCredential from azure_identity by default, with an optional key_auth feature flag for key-based authentication instead.

Core item operations cover create (serializing a #[derive(Serialize, Deserialize)] struct and writing it under a partition key), read (returning a response you deserialize into your struct with into_model()?), replace (read, mutate a field, then write the whole document back), patch (a PatchDocument built from with_add/with_remove operations targeting specific JSON paths like /newField or /oldField), and delete - all scoped to a partition key and item ID.

Use it when building a Rust application that reads and writes documents in Azure Cosmos DB's NoSQL API, especially when you want Entra ID authentication over key-based auth. Always specify the partition key on point reads and writes - the skill's own best practices call this out as required, not optional, for correct routing to the right physical partition.

Input is a Rust struct deriving Serialize/Deserialize plus its partition key and item ID. Output is the created, read, replaced, or patched document, deserialized back into your struct via into_model()?. Install it with:

cargo add azure_data_cosmos azure_identity

For key-based auth instead of Entra ID, add the feature flag: cargo add azure_data_cosmos --features key_auth.

Its own best practices: always specify the partition key, use into_model()? to deserialize responses, derive Serialize/Deserialize on every document type, prefer DeveloperToolsCredential over key auth, and reuse client instances since they are thread-safe and reusable across requests.

It's the azure_data_cosmos crate paired with azure_identity for Entra ID authentication, using serde for document serialization.

Rust developers building applications on Azure Cosmos DB's NoSQL API who need typed CRUD and patch operations against partitioned containers, with Entra ID authentication by default.