cassandra

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

Common

# 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: ""

Advanced

# Advanced 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

addresses:
  - foo:9042
  - bar:9042

addresses:
  - foo:9042,bar:9042

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.

Sensitive Information

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.

Sensitive Information

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.

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.

Sensitive Information

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}

password_authenticator

Optional configuration of Cassandra authentication parameters.

Type: object

password_authenticator.enabled

Whether to use password authentication

Type: bool

Default: false

password_authenticator.username

The username to authenticate as.

Type: string

Default: ""

password_authenticator.password

The password to authenticate with.

Sensitive Information

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: ""

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

max_retries

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

Type: int

Default: 3

backoff

Control time intervals between retry attempts.

Type: object

backoff.initial_interval

The initial period to wait between retry attempts.

Type: string

Default: "1s"

backoff.max_interval

The maximum period to wait between retry attempts.

Type: string

Default: "5s"

timeout

The client connection timeout.

Type: string

Default: "600ms"

query

A query to execute for each message.

Type: string

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.

Type: string

Requires version 3.55.0 or newer

consistency

The consistency level to use.

Type: string

Default: "QUORUM"

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

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

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

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.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