nats_stream

Type:

Available in: Self-Managed

Publish messages to a NATS Stream subject.

  • Common

  • Advanced

# Common configuration fields, showing default values
output:
  label: ""
  nats_stream:
    urls: [] # No default (required)
    cluster_id: "" # No default (required)
    subject: "" # No default (required)
    client_id: ""
    max_in_flight: 64
# All configuration fields, showing default values
output:
  label: ""
  nats_stream:
    urls: [] # No default (required)
    cluster_id: "" # No default (required)
    subject: "" # No default (required)
    client_id: ""
    max_in_flight: 64
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    auth:
      nkey_file: ./seed.nk # No default (optional)
      nkey: "" # No default (optional)
      user_credentials_file: ./user.creds # No default (optional)
      user_jwt: "" # No default (optional)
      user_nkey_seed: "" # No default (optional)
    inject_tracing_map: meta = @.merge(this) # No default (optional)
Deprecation notice

The NATS Streaming Server is being deprecated. Critical bug fixes and security fixes will be applied until June of 2023. NATS-enabled applications requiring persistence should use JetStream.

Authentication

There are a number of Redpanda Connect components that use NATS services. Each of these components support optional, advanced authentication parameters for NKeys and user credentials.

For an in-depth guide, see the NATS documentation.

NKeys

NATS server can use NKeys in several ways for authentication. The simplest approach is to configure the server with a list of user’s public keys. The server can then generate a challenge for each connection request from a client, and the client must respond to the challenge by signing it with its private NKey, configured in the nkey_file or nkey field.

For more details, see the NATS documentation.

User credentials

NATS server also supports decentralized authentication based on JSON Web Tokens (JWTs). When a server is configured to use this authentication scheme, clients need a user JWT and a corresponding NKey secret to connect.

You can use either of the following methods to supply the user JWT and NKey secret:

  • In the user_credentials_file field, enter the path to a file containing both the private key and the JWT. You can generate the file using the nsc tool.

  • In the user_jwt field, enter a plain text JWT, and in the user_nkey_seed field, enter the plain text NKey seed or private key.

For more details about authentication using JWTs, see the NATS documentation.

Performance

Send multiple messages in flight in parallel for improved performance. You can tune the number of in flight messages (or message batches) with the field max_in_flight.

Fields

urls

A list of URLs to connect to. If a list item contains commas, it will be expanded into multiple URLs.

Type: array

# Examples

urls:
  - nats://127.0.0.1:4222

urls:
  - nats://username:password@127.0.0.1:4222

cluster_id

The cluster ID to publish to.

Type: string

subject

The subject to publish to.

Type: string

client_id

The client ID to connect with.

Type: string

Default: ""

max_in_flight

The maximum number of messages to have in flight at a given time. Increase this to improve throughput.

Type: int

Default: 64

tls

Custom TLS settings can be used to override system defaults.

Type: object

tls.enabled

Whether custom TLS settings are enabled.

Type: bool

Default: false

tls.skip_cert_verify

Whether to skip server side certificate verification.

Type: bool

Default: false

tls.enable_renegotiation

Whether to allow the remote server to repeatedly request renegotiation. Enable this option if you’re seeing the error message local error: tls: no renegotiation.

Type: bool

Default: false Requires version 3.45.0 or newer

tls.root_cas

An optional root certificate authority to use. This is a string, representing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

# Examples

root_cas: |-
  -----BEGIN CERTIFICATE-----
  ...
  -----END CERTIFICATE-----

tls.root_cas_file

An optional path of a root certificate authority file to use. This is a file, often with a .pem extension, containing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.

Type: string

Default: ""

# Examples

root_cas_file: ./root_cas.pem

tls.client_certs

A list of client certificates to use. For each certificate either the fields cert and key, or cert_file and key_file should be specified, but not both.

Type: array

Default: []

# Examples

client_certs:
  - cert: foo
    key: bar

client_certs:
  - cert_file: ./example.pem
    key_file: ./example.key

tls.client_certs[].cert

A plain text certificate to use.

Type: string

Default: ""

tls.client_certs[].key

A plain text certificate key to use.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

tls.client_certs[].cert_file

The path of a certificate to use.

Type: string

Default: ""

tls.client_certs[].key_file

The path of a certificate key to use.

Type: string

Default: ""

tls.client_certs[].password

A plain text password for when the private key is password encrypted in PKCS#1 or PKCS#8 format. The obsolete pbeWithMD5AndDES-CBC algorithm is not supported for the PKCS#8 format.

Because the obsolete pbeWithMD5AndDES-CBC algorithm does not authenticate the ciphertext, it is vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

# Examples

password: foo

password: ${KEY_PASSWORD}

auth

Optional configuration of NATS authentication parameters.

Type: object

auth.nkey_file

An optional file containing a NKey seed.

Type: string

# Examples

nkey_file: ./seed.nk

auth.nkey

Your NKey seed or private key.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Requires version 3.48.0 or newer

# Examples

nkey: UDXU4RCSJNZOIQHZNWXHXORDPRTGNJAHAHFRGZNEEJCPQTT2M7NLCNF4

auth.user_credentials_file

An optional file containing user credentials which consist of a user JWT and corresponding NKey seed.

Type: string

# Examples

user_credentials_file: ./user.creds

auth.user_jwt

An optional plain text user JWT to use along with the corresponding user NKey seed.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

auth.user_nkey_seed

An optional plain text user NKey seed to use along with the corresponding user JWT.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

inject_tracing_map

EXPERIMENTAL: A Bloblang mapping used to inject an object containing tracing propagation information into outbound messages. The specification of the injected fields will match the format used by the service wide tracer.

Type: string

Requires version 4.23.0 or newer

# Examples

inject_tracing_map: meta = @.merge(this)

inject_tracing_map: root.meta.span = this