Connect

nats_stream

Available in: Self-Managed

Publish messages to a NATS Stream subject.

Common
Advanced

outputs:
  label: ""
  nats_stream:
    urls: [] # No default (required)
    cluster_id: "" # No default (required)
    subject: "" # No default (required)
    client_id: ""
    max_in_flight: 64

outputs:
  label: ""
  nats_stream:
    urls: [] # No default (required)
    max_reconnects: "" # No default (optional)
    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: []
    tls_handshake_first: false
    auth:
      nkey_file: "" # No default (optional)
      nkey: "" # No default (optional)
      user_credentials_file: "" # No default (optional)
      user_jwt: "" # No default (optional)
      user_nkey_seed: "" # No default (optional)
      user: "" # No default (optional)
      password: "" # No default (optional)
      token: "" # No default (optional)
    inject_tracing_map: "" # 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

`auth`

Optional configuration of NATS authentication parameters.

Type: object

`auth.nkey`

Your NKey seed or private key for NATS authentication. NKeys provide secure, cryptographic authentication without passwords.

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

Requires version 4.38.0 or later.

Type: string

# Examples:
nkey: UDXU4RCSJNZOIQHZNWXHXORDPRTGNJAHAHFRGZNEEJCPQTT2M7NLCNF4

`auth.nkey_file`

An optional file containing a NKey seed.

Type: string

# Examples:
nkey_file: ./seed.nk

`auth.password`

An optional plain text password (given along with the corresponding user name).

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

Type: string

`auth.token`

An optional plain text token.

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

Type: string

`auth.user`

An optional plain text user name (given along with the corresponding user password).

Type: string

`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 plaintext 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 plaintext 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

`client_id`

The client ID to connect with.

Type: string

Default: ""

`cluster_id`

The cluster ID to publish to.

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.

Requires version 4.23.0 or later.

Type: string

# Examples:
inject_tracing_map: meta = @.merge(this)

# ---

inject_tracing_map: root.meta.span = this

`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

`max_reconnects`

The maximum number of times to attempt to reconnect to the server. If negative, it will never stop trying to reconnect.

Type: int

`subject`

The subject to publish to.

Type: string

`tls`

Custom TLS settings can be used to override system defaults.

Type: object

`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: object

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[].cert_file`

The path of a 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[].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}

`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.

Requires version 3.45.0 or later.

Type: bool

Default: false

`tls.enabled`

Whether custom TLS settings are enabled.

Type: bool

Default: false

`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.skip_cert_verify`

Whether to skip server side certificate verification.

Type: bool

Default: false

`tls_handshake_first`

Whether to perform the initial TLS handshake before sending the NATS INFO protocol message. This is required when connecting to some NATS servers that expect TLS to be established immediately after connection, before any protocol negotiation.

Requires version 4.60.0 or later.

Type: bool

Default: false

`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"

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nats_stream

Authentication

NKeys

User credentials

Performance

Fields

auth

auth.nkey

auth.nkey_file

auth.password

auth.token

auth.user

auth.user_credentials_file

auth.user_jwt

auth.user_nkey_seed

client_id

cluster_id

inject_tracing_map

max_in_flight

max_reconnects

subject

tls

tls.client_certs[]

tls.client_certs[].cert

tls.client_certs[].cert_file

tls.client_certs[].key

tls.client_certs[].key_file

tls.client_certs[].password

tls.enable_renegotiation

tls.enabled

tls.root_cas

tls.root_cas_file

tls.skip_cert_verify

tls_handshake_first

urls[]

Simple online edits

Contribution guide

`auth`

`auth.nkey`

`auth.nkey_file`

`auth.password`

`auth.token`

`auth.user`

`auth.user_credentials_file`

`auth.user_jwt`

`auth.user_nkey_seed`

`client_id`

`cluster_id`

`inject_tracing_map`

`max_in_flight`

`max_reconnects`

`subject`

`tls`

`tls.client_certs[]`

`tls.client_certs[].cert`

`tls.client_certs[].cert_file`

`tls.client_certs[].key`

`tls.client_certs[].key_file`

`tls.client_certs[].password`

`tls.enable_renegotiation`

`tls.enabled`

`tls.root_cas`

`tls.root_cas_file`

`tls.skip_cert_verify`

`tls_handshake_first`

`urls[]`