Consume

type: "io.kestra.plugin.nats.Consume"

Consume messages from a NATS subject on a JetStream-enabled NATS server.

Please note that the server you run it against must have JetStream enabled for it to work. It should also have a stream configured to match the given subject.

Examples

Consume messages from any topic subject matching the kestra.> wildcard, using user password authentication.

id: nats_consume_messages
namespace: company.team

tasks:
  - id: consume
    type: io.kestra.plugin.nats.Consume
    url: nats://localhost:4222
    username: nats_user
    password: nats_password
    subject: kestra.>
    durableId: someDurableId
    pollDuration: PT5S

Properties

batchSize

• Type: integer
• Dynamic: ❌
• Required: ✔️
• Default: 10
• Minimum: >= 1

Messages are fetched by batch of given size.

deliverPolicy

• Type: string
• Dynamic: ❌
• Required: ✔️
• Default: All
• Possible Values:
  • All
  • Last
  • New
  • ByStartSequence
  • ByStartTime
  • LastPerSubject

The point in the stream to receive messages from.

Possible settings are:

• All: The default policy. The consumer will start receiving from the earliest available message.
• Last: When first consuming messages, the consumer will start receiving messages with the last message added to the stream, or the last message in the stream that matches the consumer's filter subject if defined.
• New: When first consuming messages, the consumer will only start receiving messages that were created after the consumer was created.
• ByStartSequence: When first consuming messages, start at the first message having the sequence number or the next one available.
• ByStartTime: When first consuming messages, start with messages on or after this time. The consumer is required to specify since which defines this start time.
• LastPerSubject: When first consuming messages, start with the latest one for each filtered subject currently in the stream.

pollDuration

• Type: string
• Dynamic: ❌
• Required: ✔️
• Default: 2.000000000
• Format: duration

Polling duration before processing message

If no messages are available, define the max duration to wait for new messages

subject

• Type: string
• Dynamic: ✔️
• Required: ✔️
• Min length: 1

Subject to subscribe to

url

• Type: string
• Dynamic: ✔️
• Required: ✔️
• Min length: 1

URL to connect to NATS server

The format is (nats://)server_url:port. You can also provide a connection token like so: nats://token@server_url:port

durableId

• Type: string
• Dynamic: ✔️
• Required: ❌

ID used to attach the subscription to a durable one, allowing the subscription to start back from a previous position

maxDuration

• Type: string
• Dynamic: ❌
• Required: ❌
• Format: duration

The max duration before stopping the message polling

It's not an hard limit and is evaluated every second

maxRecords

• Type: integer
• Dynamic: ❌
• Required: ❌

The max number of rows to fetch before stopping

password

• Type: string
• Dynamic: ✔️
• Required: ❌

Plaintext authentication password

since

• Type: string
• Dynamic: ✔️
• Required: ❌

Minimum message timestamp to start consumption from.

By default, we consume all messages from the subjects starting from beginning of logs or depending on the current durable id position. You can also provide an arbitrary start time to get all messages since this date for a new durable id. Note that if you don't provide a durable id, you will retrieve all messages starting from this date even after subsequent usage of this task.Must be a valid iso 8601 date.

username

• Type: string
• Dynamic: ✔️
• Required: ❌

Plaintext authentication username

Outputs

messagesCount

• Type: integer
• Required: ❌

Number of messages consumed.

uri

• Type: string
• Required: ❌
• Format: uri

URI of a Kestra internal storage file.

Definitions