p-transform

Promised out of order transform.

Usage

A Transform that uses objectMode and implements custom _write and _flush methods. transform implementation must be sync or return a promise. Callback is not supported.

Promisified pipeline and transform shortcut are provided for convenience.

import PTransform, { transform, pipeline } from 'p-transform';

await pipeline(
  new PTransform({
    transform: async file => file
  }),
  transform(async file => file);
)

Debug

Use DEBUG=p-transform:* environment variable.

For custom debug name set logName option at PTransform constructor or transform argument.

License

Apache-2.0

API

Classes

PTransform

Constants

pipeline

Promisified pipeline

Functions

transform(transform, logName)

Shortcut to create a PTransform with transform and logName.

passthrough(spy, logName)

Shortcut to create a passthrough PTransform with spy and logName.

filter(filter, logName)

Shortcut to create a filter PTransform with filter and logName.

PTransform

Kind: global class

• PTransform
  • new PTransform([options])
  • .name(name) ⇒ PTransform
  • .flushQueue() ⇒
  • .queuedTransform(chunk, encoding) ⇒

new PTransform([options])

PTransform

Param	Type	Description
[options]	Object	Options object forwarded to Transform.
[options.logName]	String	Custom name for logger.
[options.transform]	function	Transform function.
[options.queueOptions]	Object	Options forwarded to PQueue instance.

pTransform.name(name) ⇒ PTransform

Set log name.

Kind: instance method of PTransform Returns: PTransform - this

Param	Type
name	String

pTransform.flushQueue() ⇒

Wait for queue idle.

Kind: instance method of PTransform Returns: Promise

pTransform.queuedTransform(chunk, encoding) ⇒

Queued transform operation.

Kind: instance method of PTransform Returns: Promise

Param	Type
chunk	Object
encoding	String

pipeline

Promisified pipeline

Kind: global constant

transform(transform, logName)

Shortcut to create a PTransform with transform and logName.

Kind: global function

Param	Type
transform	function
logName	String

passthrough(spy, logName)

Shortcut to create a passthrough PTransform with spy and logName.

Kind: global function

Param	Type
spy	function
logName	String

filter(filter, logName)

Shortcut to create a filter PTransform with filter and logName.

Kind: global function

Param	Type
filter	function
logName	String