ockam_kafka

Beta

Uses Ockam to decrypt and read end-to-end encrypted messages from Kafka topics. You can write encrypted messages using the ockam_kafka output or by creating a Kafka Portal Inlet using Ockam Command.

Ockam Secure Channels guarantee that topic data can only be consumed by authenticated and authorized consumers, and that the data cannot be leaked or or tampered with in-flight between the producer and consumer. Neither Kafka brokers, service providers nor other components can see or manipulate the messages.

You can use Ockam to encrypt whole messages, or specific fields in a message.

Introduced in version 4.33.0.

  • Common

  • Advanced

# Common configuration fields, showing default values
input:
  label: ""
  ockam_kafka:
    kafka:
      seed_brokers: [] # No default (optional)
      topics: [] # No default (required)
      regexp_topics: false
      consumer_group: "" # No default (optional)
      auto_replay_nacks: true
    disable_content_encryption: false
    enrollment_ticket: "" # No default (optional)
    identity_name: "" # No default (optional)
    allow: self
    route_to_kafka_outlet: self
    allow_producer: self
    relay: "" # No default (optional)
    node_address: 127.0.0.1:6262
# All configuration fields, showing default values
input:
  label: ""
  ockam_kafka:
    kafka:
      seed_brokers: [] # No default (optional)
      topics: [] # No default (required)
      regexp_topics: false
      consumer_group: "" # No default (optional)
      client_id: benthos
      rack_id: ""
      checkpoint_limit: 1024
      auto_replay_nacks: true
      commit_period: 5s
      start_from_oldest: true
      metadata_max_age: 5m
      tls:
        enabled: false
        skip_cert_verify: false
        enable_renegotiation: false
        root_cas: ""
        root_cas_file: ""
        client_certs: []
      sasl: [] # No default (optional)
      multi_header: false
      batching:
        count: 0
        byte_size: 0
        period: ""
        check: ""
        processors: [] # No default (optional)
    disable_content_encryption: false
    enrollment_ticket: "" # No default (optional)
    identity_name: "" # No default (optional)
    allow: self
    route_to_kafka_outlet: self
    allow_producer: self
    relay: "" # No default (optional)
    node_address: 127.0.0.1:6262

Fields

kafka.seed_brokers

A list of broker addresses to connect to (optional). List items that contain commas are expanded into multiple addresses.

Type: array

# Examples
seed_brokers:
  - localhost:9092
seed_brokers:
  - foo:9092
  - bar:9092
seed_brokers:
  - foo:9092,bar:9092

kafka.topics

A list of topics to consume from (required). You can list multiple comma-separated topics in a single element.

If you specify a consumer_group, partitions are automatically distributed across consumers of a topic. Otherwise, all partitions are consumed.

Alternatively, add a colon after the topic name to set the explicit partitions to consume. For example, foo:0 consumes the partition 0 of the topic foo. This syntax also supports ranges. For example, foo:0-10 consumes all partitions from 0 through to 10 inclusively.

Finally, add another colon after the partition to set an explicit offset to consume from. For example, foo:0:10 consumes the partition 0 of the topic foo starting from the offset 10. If the offset is not present (or remains unspecified) then the field start_from_oldest determines which offset to start from.

Type: array

# Examples
topics:
  - foo
  - bar
topics:
  - things.*
topics:
  - foo,bar
topics:
  - foo:0
  - bar:1
  - bar:3
topics:
  - foo:0,bar:1,bar:3
topics:
  - foo:0-5

kafka.regexp_topics

Whether listed topics are interpreted as regular expression patterns for matching multiple topics. Set this value to false when explicit partitions are specified for topics.

Type: bool

Default: false

kafka.consumer_group

Assign a consumer group for the processing of messages (optional). When this value is set:

  • Partitions of specified topics are automatically distributed across consumers sharing a consumer group.

  • Partition offsets are automatically committed and resumed under this name.

Consumer groups are not supported when explicit partitions to consume from are specified in the topics field.

Type: string

kafka.client_id

An identifier for the client connection.

Type: string

Default: benthos

kafka.rack_id

A rack identifier for this client.

Type: string

Default: ""

kafka.checkpoint_limit

The maximum number of messages that are processed in parallel inside the same partition before back pressure is applied.

When a message with a specific offset is delivered to the output, the offset is only committed when all messages of previous offsets have also been delivered. This behavior ensures at-least-once delivery guarantees. However, in the event of crashes or server faults, it also increases the likelihood of duplicates. To decrease this risk, reduce the checkpoint_limit value.

Type: int

Default: 1024

kafka.auto_replay_nacks

Whether to automatically replay messages that are rejected (nacked) at the output level. If the cause of message rejections is persistent, replaying them may cause back pressure.

Set this value to false to delete rejected messages. Disabling automatic replays can greatly improve memory efficiency of high throughput streams, as the original shape of the data is immediately discarded upon consumption and mutation.

Type: bool

Default: true

kafka.commit_period

The period of time between each commit of the current partition offsets. Offsets are always committed during shutdown.

Type: string

Default: 5s

kafka.start_from_oldest

Whether to consume from the oldest available offset. Otherwise, messages are consumed from the latest offset. This setting is applied when creating a new consumer group or the saved offset no longer exists.

Type: bool

Default: true

kafka.metadata_max_age

The maximum period of time after which metadata is refreshed.

Type: string

Default: 5m

kafka.tls

Override system defaults with custom TLS settings.

Type: object

kafka.tls.enabled

Whether custom TLS settings are enabled.

Type: bool

Default: false

kafka.tls.skip_cert_verify

Whether to skip server-side certificate verification.

Type: bool

Default: false

kafka.tls.enable_renegotiation

Whether to allow the remote server to 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

kafka.tls.root_cas

Specify a root certificate authority to use (optional). This is a string that represents a certificate chain from the parent-trusted root certificate, through 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-----

kafka.tls.root_cas_file

Specify the path to a root certificate authority file (optional). This is a file, often with a .pem extension, which contains a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate.

Type: string

Default: ""

# Examples
root_cas_file: ./root_cas.pem

kafka.tls.client_certs

A list of client certificates to use. For each certificate, specify either the fields cert and key or cert_file and key_file.

Type: array

Default: []

# Examples
client_certs:
  - cert: foo
    key: bar
client_certs:
  - cert_file: ./example.pem
    key_file: ./example.key

kafka.tls.client_certs[].cert

A plain text certificate to use.

Type: string

Default: ""

kafka.tls.client_certs[].key

The 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: ""

kafka.tls.client_certs[].cert_file

The path of a certificate to use.

Type: string

Default: ""

kafka.tls.client_certs[].key_file

The path of a certificate key to use.

Type: string

Default: ""

kafka.tls.client_certs[].password

The 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.

The pbeWithMD5AndDES-CBC algorithm does not authenticate ciphertext, and is vulnerable to padding oracle attacks that may allow an attacker recover the plain text password.

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}

kafka.sasl

Specify one or more methods or mechanisms of SASL authentication, which are attempted in order (optional). If the broker supports the first SASL mechanism, all connections use it. If the first mechanism fails, the client picks the first supported mechanism. If the broker does not support any client mechanisms, all connections fail.

Type: array

# Examples
sasl:
  - mechanism: SCRAM-SHA-512
    password: bar
    username: foo

kafka.sasl[].mechanism

The SASL mechanism to use.

Type: string

Option

Summary

AWS_MSK_IAM

AWS IAM-based authentication as specified by the aws-msk-iam-auth Java library.

OAUTHBEARER

OAuth bearer-based authentication.

PLAIN

Plain text authentication.

SCRAM-SHA-256

SCRAM-based authentication as specified in RFC5802.

SCRAM-SHA-512

SCRAM-based authentication as specified in RFC5802.

none

Disable SASL authentication

kafka.sasl[].username

A username for PLAIN or SCRAM-* authentication.

Type: string

Default: ""

kafka.sasl[].password

A password for PLAIN or SCRAM-* authentication.

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

Type: string

Default: ""

kafka.sasl[].token

The token to use for a single session’s OAUTHBEARER authentication.

Type: string

Default: ""

kafka.sasl[].extensions

Key/value pairs to add to OAUTHBEARER authentication requests.

Type: object

kafka.sasl[].aws

AWS specific fields for when the mechanism is set to AWS_MSK_IAM.

Type: object

kafka.sasl[].aws.region

The AWS region to target.

Type: string

Default: ""

kafka.sasl[].aws.endpoint

Specify a custom endpoint for the AWS API.

Type: string

Default: ""

kafka.sasl[].aws.credentials

Manually configure the AWS credentials to use (optional). For more information, see the Amazon Web Services guide.

Type: object

kafka.sasl[].aws.credentials.profile

The profile from ~/.aws/credentials to use.

Type: string

Default: ""

kafka.sasl[].aws.credentials.id

The ID of credentials to use.

Type: string

Default: ""

kafka.sasl[].aws.credentials.secret

The secret for the AWS credentials in use.

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

Type: string

Default: ""

kafka.sasl[].aws.credentials.token

The token for the AWS credentials in use. This is a required value for short-term credentials.

Type: string

Default: ""

kafka.sasl[].aws.credentials.from_ec2_role

Use the credentials of a host EC2 machine configured to assume an IAM role associated with the instance.

Type: bool

Default: false

Requires version 4.2.0 or newer

kafka.sasl[].aws.credentials.role

The role ARN to assume.

Type: string

Default: ""

kafka.sasl[].aws.credentials.role_external_id

An external ID to use when assuming a role.

Type: string

Default: ""

kafka.multi_header

Decode headers into lists to allow the handling of multiple values with the same key.

Type: bool

Default: false

kafka.batching

Configure a batching policy for individual topic partitions. This allows the input to batch messages together before flushing them for processing. Batching may improve performance and is useful for windowed processing as it preserves the ordering of topic partitions.

Type: object

# Examples
batching:
  byte_size: 5000
  count: 0
  period: 1s
batching:
  count: 10
  period: 1s
batching:
  check: this.contains("END BATCH")
  count: 0
  period: 1m

kafka.batching.count

The number of messages after which the batch is flushed. Set to 0 to disable count-based batching.

Type: int

Default: 0

kafka.batching.byte_size

The number of bytes at which the batch is flushed. Set to 0 to disable size-based batching.

Type: int

Default: 0

kafka.batching.period

The period of time after which an incomplete batch is flushed regardless of its size.

Type: string

Default: ""

# Examples
period: 1s
period: 1m
period: 500ms

kafka.batching.check

A Bloblang query that returns a boolean value indicating whether a message should end a batch.

Type: string

Default: ""

# Examples
check: this.type == "end_of_transaction"

kafka.batching.processors

For aggregating and archiving message batches, you can add a list of processors to apply to a batch as it is flushed (optional). All resulting messages are flushed as a single batch even when you configure processors to split the batch into smaller batches.

Type: array

# Examples
processors:
  - archive:
      format: concatenate
processors:
  - archive:
      format: lines
processors:
  - archive:
      format: json_array

disable_content_encryption

Disables Kafka message encryption.

If this value is set to true:

  • Only message payloads remain unencrypted. This setting does not disable TLS or any other transport-layer encryption that may also be enabled.

  • All other ockam_kafka inlets and outlets in a topic must also have their settings set to true.

Type: bool

Default: false

enrollment_ticket

The path to a file or a URL where the enrollment ticket value is stored, or an inline hex-encoded value of the enrollment ticket (optional).

You can generate a new ticket using the ockam project ticket command.

Type: string

identity_name

The name of the Ockam identity to use. If this value is not provided, the default Ockam identity is automatically generated and used (optional).

Type: string

allow

Use in conjunction with the route_to_kafka_outlet field to specify an access control policy for the Kafka Portal Outlet.

For example, setting this value to kafka_us_east forces the Kafka Outlet to present an Ockam credential, which confirms that the Outlet has the attribute kafka_us_east=true.

Type: string

Default: self

route_to_kafka_outlet

The route to reach the Kafka Portal Outlet of your Ockam portal. For example, /project/default.

Type: string

Default: self

allow_producer

Specify an access control policy for producers.

For example, setting this value to orders_producer forces the producer to present an Ockam credential, which confirms that the producer has the attribute orders_producer=true.

Type: string

Default: self

relay

Make the Ockam node accessible through a relay with the supplied name (optional).

For example, setting this value to orders_consumer would require you to set the route_to_consumer on any producer to /project/default/service/forward_to_orders_consumer/secure/api.

Type: string

node_address

The TCP listening address of the Ockam node.

Type: string

Default: 127.0.0.1:6262