kafka_franz

A Kafka output using the Franz Kafka client library.

Common
Advanced

# Common config fields, showing default values
output:
  label: ""
  kafka_franz:
    seed_brokers: [] # No default (required)
    topic: "" # No default (required)
    key: "" # No default (optional)
    partition: ${! metadata("partition") } # No default (optional)
    metadata:
      include_prefixes: []
      include_patterns: []
    max_in_flight: 10
    batching:
      count: 0
      byte_size: 0
      period: ""
      jitter: 0
      check: ""

# All config fields, showing default values
output:
  label: ""
  kafka_franz:
    seed_brokers: [] # No default (required)
    topic: "" # No default (required)
    key: "" # No default (optional)
    partitioner: "" # No default (optional)
    uniform_bytes_options:
      bytes: 1MB
      adaptive: false
      keys: false
    partition: ${! metadata("partition") } # No default (optional)
    client_id: bento
    rack_id: ""
    idempotent_write: true
    metadata:
      include_prefixes: []
      include_patterns: []
    max_in_flight: 10
    timeout: 10s
    batching:
      count: 0
      byte_size: 0
      period: ""
      jitter: 0
      check: ""
      processors: [] # No default (optional)
    max_message_bytes: 1MB
    max_buffered_bytes: "0"
    max_buffered_records: 10000
    broker_write_max_bytes: 100MiB
    metadata_max_age: 5m
    compression: "" # No default (optional)
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    sasl: [] # No default (optional)

Writes a batch of messages to Kafka brokers and waits for acknowledgement before propagating it back to the input.

This output often out-performs the traditional kafka output as well as providing more useful logs and error messages.

Fields

`seed_brokers`

A list of broker addresses to connect to in order to establish connections. If an item of the list contains commas it will be expanded into multiple addresses.

Type: array

# Examples

seed_brokers:
  - localhost:9092

seed_brokers:
  - foo:9092
  - bar:9092

seed_brokers:
  - foo:9092,bar:9092

`topic`

A topic to write messages to. This field supports interpolation functions.

Type: string

`key`

An optional key to populate for each message. This field supports interpolation functions.

Type: string

`partitioner`

Override the default murmur2 hashing partitioner.

Type: string

Option	Summary
`least_backup`	Chooses the least backed up partition (the partition with the fewest amount of buffered records). Partitions are selected per batch.
`manual`	Manually select a partition for each message, requires the field `partition` to be specified.
`murmur2_hash`	Kafka's default hash algorithm that uses a 32-bit murmur2 hash of the key to compute which partition the record will be on.
`round_robin`	Round-robin's messages through all available partitions. This algorithm has lower throughput and causes higher CPU load on brokers, but can be useful if you want to ensure an even distribution of records to partitions.
`uniform_bytes`	Partitions based on byte size, with options for adaptive partitioning and key-based hashing in the `uniform_bytes_options` component.

`uniform_bytes_options`

Sets partitioner options when partitioner is of type uniform_bytes. These values will otherwise be ignored. Note, that future versions will likely see this approach reworked.

Type: object

`uniform_bytes_options.bytes`

The number of bytes the partitioner will return the same partition for.

Type: string
Default: "1MB"

`uniform_bytes_options.adaptive`

Sets a slight imbalance so that the partitioner can produce more to brokers that are less loaded.

Type: bool
Default: false

`uniform_bytes_options.keys`

If true, uses standard hashing based on record key for records with non-nil keys.

Type: bool
Default: false

`partition`

An optional explicit partition to set for each message. This field is only relevant when the partitioner is set to manual. The provided interpolation string must be a valid integer. This field supports interpolation functions.

Type: string

# Examples

partition: ${! metadata("partition") }

`client_id`

An identifier for the client connection.

Type: string
Default: "bento"

`rack_id`

A rack identifier for this client.

Type: string
Default: ""

`idempotent_write`

Enable the idempotent write producer option. This requires the IDEMPOTENT_WRITE permission on CLUSTER and can be disabled if this permission is not available.

Type: bool
Default: true

`metadata`

Determine which (if any) metadata values should be added to messages as headers.

Type: object

`metadata.include_prefixes`

Provide a list of explicit metadata key prefixes to match against.

Type: array
Default: []

# Examples

include_prefixes:
  - foo_
  - bar_

include_prefixes:
  - kafka_

include_prefixes:
  - content-

`metadata.include_patterns`

Provide a list of explicit metadata key regular expression (re2) patterns to match against.

Type: array
Default: []

# Examples

include_patterns:
  - .*

include_patterns:
  - _timestamp_unix$

`max_in_flight`

The maximum number of batches to be sending in parallel at any given time.

Type: int
Default: 10

`timeout`

The maximum period of time to wait for message sends before abandoning the request and retrying

Type: string
Default: "10s"

`batching`

Allows you to configure a batching policy.

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

batching:
  count: 10
  jitter: 0.1
  period: 10s

`batching.count`

A number of messages at which the batch should be flushed. If 0 disables count based batching.

Type: int
Default: 0

`batching.byte_size`

An amount of bytes at which the batch should be flushed. If 0 disables size based batching.

Type: int
Default: 0

`batching.period`

A period in which an incomplete batch should be flushed regardless of its size.

Type: string
Default: ""

# Examples

period: 1s

period: 1m

period: 500ms

`batching.jitter`

A non-negative factor that adds random delay to batch flush intervals, where delay is determined uniformly at random between 0 and jitter * period. For example, with period: 100ms and jitter: 0.1, each flush will be delayed by a random duration between 0-10ms.

Type: float
Default: 0

# Examples

jitter: 0.01

jitter: 0.1

jitter: 1

`batching.check`

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

Type: string
Default: ""

# Examples

check: this.type == "end_of_transaction"

`batching.processors`

A list of processors to apply to a batch as it is flushed. This allows you to aggregate and archive the batch however you see fit. Please note that all resulting messages are flushed as a single batch, therefore splitting the batch into smaller batches using these processors is a no-op.

Type: array

# Examples

processors:
  - archive:
      format: concatenate

processors:
  - archive:
      format: lines

processors:
  - archive:
      format: json_array

`max_message_bytes`

The maximum space in bytes than an individual message may take, messages larger than this value will be rejected. This field corresponds to Kafka's max.message.bytes.

Type: string
Default: "1MB"

# Examples

max_message_bytes: 100MB

max_message_bytes: 50mib

`max_buffered_bytes`

max_buffered_bytes sets the max amount of bytes that the client will buffer while producing, blocking produces until records are finished if this limit is reached. This overrides the unlimited default.

Type: string
Default: "0"
Requires version 1.21.0 or newer

# Examples

max_buffered_bytes: 100MB

max_buffered_bytes: 50mib

`max_buffered_records`

Sets the max amount of records the client will buffer, blocking produces until records are finished if this limit is reached. This overrides the franz-kafka default of 10,000.

Type: int
Default: 10000

`broker_write_max_bytes`

broker_write_max_bytes upper bounds the number of bytes written to a broker connection in a single write, overriding the default 100MiB. This number corresponds to the a broker's socket.request.max.bytes.

Type: string
Default: "100MiB"
Requires version 1.21.0 or newer

# Examples

broker_write_max_bytes: 100MB

broker_write_max_bytes: 50mib

`metadata_max_age`

This sets the maximum age for the client's cached metadata, to allow detection of new topics, partitions, etc.

Type: string
Default: "5m"

`compression`

Optionally set an explicit compression type. The default preference is to use snappy when the broker supports it, and fall back to none if not.

Type: string
Options: lz4, snappy, gzip, none, zstd.

`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 1.0.0 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.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

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.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

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. Warning: Since it does not authenticate the ciphertext, it is vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

Type: string
Default: ""

# Examples

password: foo

password: ${KEY_PASSWORD}

`sasl`

Specify one or more methods of SASL authentication. SASL is tried in order; if the broker supports the first mechanism, all connections will use that mechanism. If the first mechanism fails, the client will pick the first supported mechanism. If the broker does not support any client mechanisms, connections will fail.

Type: array

# Examples

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

sasl:
  - kerberos_config_path: /etc/krb5.conf
    keytab_path: /etc/security/keytabs/kafka.keytab
    mechanism: GSSAPI
    principal: kafka_client/host.example.com
    realm: EXAMPLE.COM
    service_name: 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.
`GSSAPI`	GSSAPI / Kerberos based authentication.
`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

`sasl[].username`

A username to provide for PLAIN or SCRAM-* authentication.

Type: string
Default: ""

`sasl[].password`

A password to provide for PLAIN or SCRAM-* authentication.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

Type: string
Default: ""

`sasl[].token`

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

Type: string
Default: ""

`sasl[].oauth2`

Allows you to specify open authentication via OAuth version 2 using the client credentials token flow.

Type: object
Requires version 1.18.0 or newer

`sasl[].oauth2.enabled`

Whether to use OAuth version 2 in requests.

Type: bool
Default: false

`sasl[].oauth2.client_key`

A value used to identify the client to the token provider.

Type: string
Default: ""

`sasl[].oauth2.client_secret`

A secret used to establish ownership of the client key.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

Type: string
Default: ""

`sasl[].oauth2.token_url`

The URL of the token provider.

Type: string
Default: ""

`sasl[].oauth2.scopes`

A list of optional requested permissions.

Type: array
Default: []

`sasl[].oauth2.endpoint_params`

A list of optional endpoint parameters, values should be arrays of strings.

Type: object

`sasl[].extensions`

Key/value pairs to add to OAUTHBEARER authentication requests.

Type: object

`sasl[].aws`

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

Type: object

`sasl[].aws.region`

The AWS region to target.

Type: string
Default: ""

`sasl[].aws.endpoint`

Allows you to specify a custom endpoint for the AWS API.

Type: string
Default: ""

`sasl[].aws.credentials`

Optional manual configuration of AWS credentials to use. More information can be found in this document.

Type: object

`sasl[].aws.credentials.profile`

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

Type: string
Default: ""

`sasl[].aws.credentials.id`

The ID of credentials to use.

Type: string
Default: ""

`sasl[].aws.credentials.secret`

The secret for the credentials being used.

Secret

This field contains sensitive information that usually shouldn't be added to a config directly, read our secrets page for more info.

Type: string
Default: ""

`sasl[].aws.credentials.token`

The token for the credentials being used, required when using short term credentials.

Type: string
Default: ""

`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

`sasl[].aws.credentials.role`

A role ARN to assume.

Type: string
Default: ""

`sasl[].aws.credentials.role_external_id`

An external ID to provide when assuming a role.

Type: string
Default: ""

`sasl[].aws.credentials.expiry_window`

Allow the credentials to trigger refreshing prior to the credentials actually expiring. This is beneficial so race conditions with expiring credentials do not cause requests to fail. For example '10s' would refresh credentials ten seconds before expiration. Setting to a duration of 0 disables the expiry window.

Type: string
Default: ""

`sasl[].kerberos_config_path`

The path to a kerberos configuration file (krb5.conf). Used when mechanism is set to GSSAPI.

Type: string
Default: "/etc/krb5.conf"

`sasl[].keytab_path`

The path to a keytab file to use for authentication with the kerberos client.

Type: string
Default: ""

`sasl[].principal`

The principal to use for kerberos authentication, e.g. kafka_client/host.example.com.

Type: string
Default: ""

`sasl[].realm`

The realm to use for kerberos authentication.

Type: string
Default: ""

`sasl[].service_name`

The service name to use when constructing a service ticket with the kerberos client, e.g. kafka (default).

Type: string
Default: "kafka"

`sasl[].disable_pafx_fast`

Controls whether to use PA_FX_FAST in AS_REQ (pre-authentication fast).

Type: bool
Default: false

Fields

Fields​

seed_brokers​

topic​

key​

partitioner​

uniform_bytes_options​

uniform_bytes_options.bytes​

uniform_bytes_options.adaptive​

uniform_bytes_options.keys​

partition​

client_id​

rack_id​

idempotent_write​

metadata​

metadata.include_prefixes​

metadata.include_patterns​

max_in_flight​

timeout​

batching​

batching.count​

batching.byte_size​

batching.period​

batching.jitter​

batching.check​

batching.processors​

max_message_bytes​

max_buffered_bytes​

max_buffered_records​

broker_write_max_bytes​

metadata_max_age​

compression​

tls​

tls.enabled​

tls.skip_cert_verify​

tls.enable_renegotiation​

tls.root_cas​

tls.root_cas_file​

tls.client_certs​

tls.client_certs[].cert​

tls.client_certs[].key​

tls.client_certs[].cert_file​

tls.client_certs[].key_file​

tls.client_certs[].password​

sasl​

sasl[].mechanism​

sasl[].username​

sasl[].password​

sasl[].token​

sasl[].oauth2​

sasl[].oauth2.enabled​

sasl[].oauth2.client_key​

sasl[].oauth2.client_secret​

sasl[].oauth2.token_url​

sasl[].oauth2.scopes​

sasl[].oauth2.endpoint_params​

sasl[].extensions​

sasl[].aws​

sasl[].aws.region​

sasl[].aws.endpoint​

sasl[].aws.credentials​

sasl[].aws.credentials.profile​

sasl[].aws.credentials.id​

sasl[].aws.credentials.secret​

sasl[].aws.credentials.token​

sasl[].aws.credentials.from_ec2_role​

sasl[].aws.credentials.role​

sasl[].aws.credentials.role_external_id​

sasl[].aws.credentials.expiry_window​

sasl[].kerberos_config_path​

sasl[].keytab_path​

sasl[].principal​

sasl[].realm​

sasl[].service_name​

sasl[].disable_pafx_fast​

Fields

`seed_brokers`

`topic`

`key`

`partitioner`

`uniform_bytes_options`

`uniform_bytes_options.bytes`

`uniform_bytes_options.adaptive`

`uniform_bytes_options.keys`

`partition`

`client_id`

`rack_id`

`idempotent_write`

`metadata`

`metadata.include_prefixes`

`metadata.include_patterns`

`max_in_flight`

`timeout`

`batching`

`batching.count`

`batching.byte_size`

`batching.period`

`batching.jitter`

`batching.check`

`batching.processors`

`max_message_bytes`

`max_buffered_bytes`

`max_buffered_records`

`broker_write_max_bytes`

`metadata_max_age`

`compression`

`tls`

`tls.enabled`

`tls.skip_cert_verify`

`tls.enable_renegotiation`

`tls.root_cas`

`tls.root_cas_file`

`tls.client_certs`

`tls.client_certs[].cert`

`tls.client_certs[].key`

`tls.client_certs[].cert_file`

`tls.client_certs[].key_file`

`tls.client_certs[].password`

`sasl`

`sasl[].mechanism`

`sasl[].username`

`sasl[].password`

`sasl[].token`

`sasl[].oauth2`

`sasl[].oauth2.enabled`

`sasl[].oauth2.client_key`

`sasl[].oauth2.client_secret`

`sasl[].oauth2.token_url`

`sasl[].oauth2.scopes`

`sasl[].oauth2.endpoint_params`

`sasl[].extensions`

`sasl[].aws`

`sasl[].aws.region`

`sasl[].aws.endpoint`

`sasl[].aws.credentials`

`sasl[].aws.credentials.profile`

`sasl[].aws.credentials.id`

`sasl[].aws.credentials.secret`

`sasl[].aws.credentials.token`

`sasl[].aws.credentials.from_ec2_role`

`sasl[].aws.credentials.role`

`sasl[].aws.credentials.role_external_id`

`sasl[].aws.credentials.expiry_window`

`sasl[].kerberos_config_path`

`sasl[].keytab_path`

`sasl[].principal`

`sasl[].realm`

`sasl[].service_name`

`sasl[].disable_pafx_fast`