cassandra

Runs a query against a Cassandra database for each message in order to insert data.

  • Common

  • Advanced

# Common config fields, showing default values
output:
  label: ""
  cassandra:
    addresses: [] # No default (required)
    timeout: 600ms
    query: "" # No default (required)
    args_mapping: "" # No default (optional)
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
# All config fields, showing default values
output:
  label: ""
  cassandra:
    addresses: [] # No default (required)
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    password_authenticator:
      enabled: false
      username: ""
      password: ""
    disable_initial_host_lookup: false
    max_retries: 3
    backoff:
      initial_interval: 1s
      max_interval: 5s
    timeout: 600ms
    query: "" # No default (required)
    args_mapping: "" # No default (optional)
    consistency: QUORUM
    logged_batch: true
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)

Query arguments can be set using a bloblang array for the fields using the args_mapping field.

When populating timestamp columns the value must either be a string in ISO 8601 format (2006-01-02T15:04:05Z07:00), or an integer representing unix time in seconds.

Performance

This output benefits from sending multiple messages in flight in parallel for improved performance. You can tune the max number of in flight messages (or message batches) with the field max_in_flight.

This output benefits from sending messages as a batch for improved performance. Batches can be formed at both the input and output level. You can find out more in this doc.

Examples

Basic Inserts

If we were to create a table with some basic columns with CREATE TABLE foo.bar (id int primary key, content text, created_at timestamp);, and were processing JSON documents of the form {"id":"342354354","content":"hello world","timestamp":1605219406} using logged batches, we could populate our table with the following config:

output:
  cassandra:
    addresses:
      - localhost:9042
    query: 'INSERT INTO foo.bar (id, content, created_at) VALUES (?, ?, ?)'
    args_mapping: |
      root = [
        this.id,
        this.content,
        this.timestamp
      ]
    batching:
      count: 500
      period: 1s

Insert JSON Documents

The following example inserts JSON documents into the table footable of the keyspace foospace using INSERT JSON (https://cassandra.apache.org/doc/latest/cql/json.html#insert-json).

output:
  cassandra:
    addresses:
      - localhost:9042
    query: 'INSERT INTO foospace.footable JSON ?'
    args_mapping: 'root = [ this ]'
    batching:
      count: 500
      period: 1s

Fields

addresses[]

A list of Cassandra nodes to connect to. Multiple comma separated addresses can be specified on a single line.

Type: array

# Examples:
addresses:
  - "localhost:9042"

  - "foo:9042"
  - "bar:9042"

  - "foo:9042,bar:9042"

args_mapping

A Bloblang mapping that can be used to provide arguments to Cassandra queries. The result of the query must be an array containing a matching number of elements to the query arguments.

Requires version 3.55.0 or later.

Type: string

backoff

Control time intervals between retry attempts.

Type: object

backoff.initial_interval

The initial period to wait between retry attempts. The retry interval increases for each failed attempt, up to the backoff.max_interval value.

Type: string

Default: 1s

backoff.max_interval

The maximum period to wait between retry attempts.

Type: string

Default: 5s

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.byte_size

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

Type: int

Default: 0

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.count

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

# Examples:
processors:
  - archive:
      format: concatenate

  - archive:
      format: lines

  - archive:
      format: json_array

consistency

The consistency level to use.

Type: string

Default: QUORUM

Options: ANY, ONE, TWO, THREE, QUORUM, ALL, LOCAL_QUORUM, EACH_QUORUM, LOCAL_ONE

disable_initial_host_lookup

If enabled the driver will not attempt to get host info from the system.peers table. This can speed up queries but will mean that data_centre, rack and token information will not be available.

Type: bool

Default: false

logged_batch

If enabled the driver will perform a logged batch. Disabling this prompts unlogged batches to be used instead, which are less efficient but necessary for alternative storages that do not support logged batches.

Type: bool

Default: true

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_retries

The maximum number of retries before giving up on a request.

Type: int

Default: 3

password_authenticator

Optional configuration of Cassandra authentication parameters.

Type: object

password_authenticator.enabled

Whether to use password authentication

Type: bool

Default: false

password_authenticator.password

The password to authenticate with.

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

Type: string

Default: ""

password_authenticator.username

The username to authenticate as.

Type: string

Default: ""

query

A query to execute for each message.

Type: string

timeout

The client connection timeout.

Type: string

Default: 600ms

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

  - 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