Data Sinks

A data sink is reference object for a data target that is external to the database. It consists of the location & connection information to that external target. A data sink can make use of a credential object for storing remote authentication information.

The following data sink types are supported:

  • HTTP/HTTPS Webhook
  • Apache Kafka

Data sinks perform no function by themselves, but act as proxies for transmitting data when referenced as a destination in the creation of a table monitor (see also the CREATE STREAM command in SQL).

Note

Kafka data sinks will be validated upon creation, by default, and will fail to be created if an authorized connection cannot be established.

Managing Data Sinks

A data sink can be managed using the following API endpoint calls. For managing data sinks in SQL, see CREATE DATA SINK.

API CallDescription
/create/datasinkCreates a data sink, given a location and connection information
/alter/datasinkModifies the properties of a data sink, validating the new connection
/drop/datasinkRemoves the data sink reference from the database; optionally removing all dependent table monitors as well
/show/datasinkOutputs the data sink properties
/grant/permissionGrants the permission for a user to connect to a data sink
/revoke/permissionRevokes the permission for a user to connect to a data sink

Creating a Data Sink

To create a data sink, kin_dsink, that targets Apache Kafka, in Python:

1
2
3
4
5
6
7
8
db.create_datasink(
    name = 'kin_dsink',
    destination = 'kafka://kafka.abc.com:9092',
    options = {
        'kafka_topic_name': 'kafka_topic',
        'credential': 'kafka_credential'
    }
)

Provider-Specific Syntax

Several authentication schemes across multiple providers are supported.

Webhook

HTTP
1
2
3
4
h_db.create_datasink(
    name = '<data sink name>',
    destination = 'http://<webhook.host>:<webhook.port>'
)
HTTPS
1
2
3
4
5
6
7
h_db.create_datasink(
    name = '<data sink name>',
    destination = 'https://<webhook.host>:<webhook.port>',
    options = {
        credential = '<credential name>'
    }
)

Kafka

No Auth
1
2
3
4
5
6
7
h_db.create_datasink(
    name = '<data sink name>',
    destination = 'kafka://<kafka.host>:<kafka.port>',
    options = {
        kafka_topic_name = '<kafka topic name>'
    }
)
Credential Auth
1
2
3
4
5
6
7
8
h_db.create_datasink(
    name = '<data sink name>',
    destination = 'kafka://<kafka.host>:<kafka.port>',
    options = {
        kafka_topic_name = '<kafka topic name>',
        credential = '<credential name>'
    }
)