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Extension Port Stream
A module for creating a Node-style stream over a WebExtension Runtime.Port object.
Breaking changes from v4 to v5
- Chunking mode is enabled by default (see the Usage section below).
- Node.js-style
Buffermessages are no longer supported.
Additionally, the timing of logging, errors, and callbacks may be handled differently.
Usage
By default, ExtensionPortStream will send messages in 64MB chunks on Chromium-based browsers.
When this mode is used the receiving end must also use ExtensionPortStream in its default mode.
import { ExtensionPortStream } from "extension-port-stream";
extension.runtime.onConnect.addListener(connectRemote);
const portStream = new ExtensionPortStream(remotePort, {
chunkSize: 0, // disable chunking
});
// Enjoy!To disable chunking set the chunkSize option to 0. This will make the transport
mostly backwards compatible with v4.
import { ExtensionPortStream } from "extension-port-stream";
extension.runtime.onConnect.addListener(connectRemote);
const portStream = new ExtensionPortStream(remotePort, {
chunkSize: 0, // disable chunking
});
// Enjoy!Events
ExtensionPortStream extends Node.js Duplex stream, so it inherits all EventEmitter capabilities. Additionally, it emits the following custom events:
message-too-large
Emitted when a message is too large to send in a single postMessage call and needs to be chunked. This event is only emitted when chunking is enabled (default).
import {
ExtensionPortStream,
MessageTooLargeEventData,
} from "extension-port-stream";
const portStream = new ExtensionPortStream(remotePort);
portStream.on("message-too-large", (data: MessageTooLargeEventData) => {
console.log(
`Message too large (${
JSON.stringify(data.message).length
} bytes), chunking into ${data.chunkSize}-byte pieces`
);
console.log("Original error:", data.originalError.message);
});Running tests
yarn test