Skip to content
Wombat

azure_cosmosdb

Executes a SQL query against Azure CosmosDB and creates a batch of messages from each page of items.

Introduced in version v4.25.0.

# Common config fields, showing default values
input:
  label: ""
  azure_cosmosdb:
    endpoint: https://localhost:8081 # No default (optional)
    account_key: '!!!SECRET_SCRUBBED!!!' # No default (optional)
    connection_string: '!!!SECRET_SCRUBBED!!!' # No default (optional)
    database: testdb # No default (required)
    container: testcontainer # No default (required)
    partition_keys_map: root = "blobfish" # No default (required)
    query: SELECT c.foo FROM testcontainer AS c WHERE c.bar = "baz" AND c.timestamp < @timestamp # No default (required)
    args_mapping: |- # No default (optional)
      root = [
        { "Name": "@name", "Value": "benthos" },
      ]
    auto_replay_nacks: true

Cross-partition queries

Cross-partition queries are currently not supported by the underlying driver. For every query, the PartitionKey values must be known in advance and specified in the config. See details.

Credentials

You can use one of the following authentication mechanisms:

  • Set the endpoint field and the account_key field
  • Set only the endpoint field to use DefaultAzureCredential
  • Set the connection_string field

Metadata

This component adds the following metadata fields to each message:

- activity_id
- request_charge

You can access these metadata fields using function interpolation.

Examples

Execute a parametrized SQL query to select documents from a container.

yaml
input:
  azure_cosmosdb:
    endpoint: http://localhost:8080
    account_key: C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==
    database: blobbase
    container: blobfish
    partition_keys_map: root = "AbyssalPlain"
    query: SELECT * FROM blobfish AS b WHERE b.species = @species
    args_mapping: |
      root = [
          { "Name": "@species", "Value": "smooth-head" },
      ]

Fields

endpoint

CosmosDB endpoint.

Type: string

# Examples


endpoint: https://localhost:8081

account_key

Account key.

Type: string

# Examples


account_key: C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==

connection_string

Connection string.

Type: string

# Examples


connection_string: AccountEndpoint=https://localhost:8081/;AccountKey=C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==;

database

Database.

Type: string

# Examples


database: testdb

container

Container.

Type: string

# Examples


container: testcontainer

partition_keys_map

A Bloblang mapping which should evaluate to a single partition key value or an array of partition key values of type string, integer or boolean. Currently, hierarchical partition keys are not supported so only one value may be provided.

Type: string

# Examples


partition_keys_map: root = "blobfish"


partition_keys_map: root = 41


partition_keys_map: root = true


partition_keys_map: root = null


partition_keys_map: root = now().ts_format("2006-01-02")

query

The query to execute

Type: string

# Examples


query: SELECT c.foo FROM testcontainer AS c WHERE c.bar = "baz" AND c.timestamp < @timestamp

args_mapping

A Bloblang mapping that, for each message, creates a list of arguments to use with the query.

Type: string

# Examples


args_mapping: |-
  root = [
    { "Name": "@name", "Value": "benthos" },
  ]

batch_count

The maximum number of messages that should be accumulated into each batch. Use ‘-1’ specify dynamic page size.

Type: int

Default: -1

auto_replay_nacks

Whether messages that are rejected (nacked) at the output level should be automatically replayed indefinitely, eventually resulting in back pressure if the cause of the rejections is persistent. If set to false these messages will instead be deleted. Disabling auto replays can greatly improve memory efficiency of high throughput streams as the original shape of the data can be discarded immediately upon consumption and mutation.

Type: bool

Default: true

CosmosDB emulator

If you wish to run the CosmosDB emulator that is referenced in the documentation here, the following Docker command should do the trick:

Terminal window
> docker run --rm -it -p 8081:8081 --name=cosmosdb -e AZURE_COSMOS_EMULATOR_PARTITION_COUNT=10 -e AZURE_COSMOS_EMULATOR_ENABLE_DATA_PERSISTENCE=false mcr.microsoft.com/cosmosdb/linux/azure-cosmos-emulator

Note: AZURE_COSMOS_EMULATOR_PARTITION_COUNT controls the number of partitions that will be supported by the emulator. The bigger the value, the longer it takes for the container to start up.

Additionally, instead of installing the container self-signed certificate which is exposed via [mitmproxy](https://localhost:8081/_explorer/emulator.pem, you can run https://mitmproxy.org/) like so:

Terminal window
> mitmproxy -k --mode "reverse:https://localhost:8081"

Then you can access the CosmosDB UI via http://localhost:8080/_explorer/index.html and use http://localhost:8080 as the CosmosDB endpoint.