hdfs

Type:

Sends message parts as files to a HDFS directory.

  • Common

  • Advanced

# Common config fields, showing default values
output:
  label: ""
  hdfs:
    hosts: [] # No default (required)
    user: ""
    directory: "" # No default (required)
    path: ${!count("files")}-${!timestamp_unix_nano()}.txt
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
# All config fields, showing default values
output:
  label: ""
  hdfs:
    hosts: [] # No default (required)
    user: ""
    directory: "" # No default (required)
    path: ${!count("files")}-${!timestamp_unix_nano()}.txt
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)

Each file is written with the path specified with the 'path' field, in order to have a different path for each object you should use function interpolations described here.

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.

Fields

hosts

A list of target host addresses to connect to.

Type: array

# Examples

hosts: localhost:9000

user

A user ID to connect as.

Type: string

Default: ""

directory

A directory to store message files within. If the directory does not exist it will be created. This field supports interpolation functions.

Type: string

path

The path to upload messages as, interpolation functions should be used in order to generate unique file paths. This field supports interpolation functions.

Type: string

Default: "${!count(\"files\")}-${!timestamp_unix_nano()}.txt"

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