Skip to main content

cassandra

BETA

This component is mostly stable but breaking changes could still be made outside of major version releases if a fundamental problem with the component is found.

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

# 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: ""
      jitter: 0
      check: ""

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​

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

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 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}

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.

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: ""

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 1.0.0 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: 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