WebAssembly (Wasm) transform

Modify events using an embedded WebAssembly (Wasm) virtual machine

status: beta egress: stream state: stateful

Requirements

Vector must be built with the wasm feature. This is not enabled by default. See the Building Vector docs for more info.*

Configuration

Example configurations

{
  "transforms": {
    "my_transform_id": {
      "type": "wasm",
      "inputs": "my-source-or-transform-id",
      "artifact_cache": "/etc/vector/artifacts",
      "module": "./modules/example.wasm"
    }
  }
}
[transforms.my_transform_id]
type = "wasm"
inputs = "my-source-or-transform-id"
artifact_cache = "/etc/vector/artifacts"
module = "./modules/example.wasm"
---
transforms:
  my_transform_id:
    type: wasm
    inputs: my-source-or-transform-id
    artifact_cache: /etc/vector/artifacts
    module: ./modules/example.wasm
{
  "transforms": {
    "my_transform_id": {
      "type": "wasm",
      "inputs": "my-source-or-transform-id",
      "artifact_cache": "/etc/vector/artifacts",
      "heap_max_size": 10485760,
      "module": "./modules/example.wasm"
    }
  }
}
[transforms.my_transform_id]
type = "wasm"
inputs = "my-source-or-transform-id"
artifact_cache = "/etc/vector/artifacts"
heap_max_size = 10_485_760
module = "./modules/example.wasm"
---
transforms:
  my_transform_id:
    type: wasm
    inputs: my-source-or-transform-id
    artifact_cache: /etc/vector/artifacts
    heap_max_size: 10485760
    module: ./modules/example.wasm

artifact_cache

required string
The directory where Vector should store the artifact it builds of this WASM module. Typically, all WASM modules share this.

heap_max_size

optional uint
The maximum size of the heap of this module, in bytes. (This includes the module itself, default is 10 MB.)
default: 1.048576e+07 (bytes)

inputs

required [string]

A list of upstream source or transform IDs. Wildcards (*) are supported but must be the last character in the ID.

See configuration for more info.

Array string literal
Examples
[
  "my-source-or-transform-id",
  "prefix-*"
]

module

required string
The file path of the .wasm or .wat module.

Telemetry

Metrics

link

events_in_total

counter
The number of events accepted by this component either from tagged origin like file and uri, or cumulatively from other origins.
component_kind required
The Vector component kind.
component_name required
The Vector component name.
component_type required
The Vector component type.
container_name optional
The name of the container from which the event originates.
file optional
The file from which the event originates.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the event originates.
peer_path optional
The pathname from which the event originates.
pod_name optional
The name of the pod from which the event originates.
uri optional
The sanitized URI from which the event originates.

events_out_total

counter
The total number of events emitted by this component.
component_kind required
The Vector component kind.
component_name required
The Vector component name.
component_type required
The Vector component type.

processed_bytes_total

counter
The number of bytes processed by the component.
component_kind required
The Vector component kind.
component_name required
The Vector component name.
component_type required
The Vector component type.
container_name optional
The name of the container from which the bytes originate.
file optional
The file from which the bytes originate.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the bytes originate.
peer_path optional
The pathname from which the bytes originate.
pod_name optional
The name of the pod from which the bytes originate.
uri optional
The sanitized URI from which the bytes originate.

processed_events_total

counter
The total number of events processed by this component. This metric is deprecated in place of using events_in_total and events_out_total metrics.
component_kind required
The Vector component kind.
component_name required
The Vector component name.
component_type required
The Vector component type.

How it works

State

This component is stateful, meaning its behavior changes based on previous inputs (events). State is not preserved across restarts, therefore state-dependent behavior will reset between restarts and depend on the inputs (events) received since the most recent restart.