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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: []
query: ""
args_mapping: ""
timeout: 600ms
max_in_flight: 1
batching:
count: 0
byte_size: 0
period: ""
check: ""

Query arguments can be set using interpolation functions in the args field or by creating 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 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}, 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

Fields

addresses

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

Type: array
Default: []

# 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.

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.

Type: string
Default: ""

tls.client_certs[].cert_file

The path to a certificate to use.

Type: string
Default: ""

tls.client_certs[].key_file

The path of a certificate key to use.

Type: string
Default: ""

password_authenticator

An object containing the username and password.

Type: object

password_authenticator.enabled

Whether to use password authentication.

Type: bool
Default: false

password_authenticator.username

A username.

Type: string
Default: ""

password_authenticator.password

A password.

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

query

A query to execute for each message.

Type: string
Default: ""

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
Default: ""
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.

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"
Requires version 3.63.0 or newer

max_in_flight

The maximum number of messages to have in flight at a given time. Increase this to improve throughput.

Type: int
Default: 1

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
Default: []

# Examples
processors:
- archive:
format: lines
processors:
- archive:
format: json_array
processors:
- merge_json: {}