@johnlindquist/clipboard

General Clipboard Listener

A Cross-Platform clipboard listener that listens for both text and image (screenshots). Designed for NodeJS, not for web. Provides API to read and write text/image from/to clipboard.

Forked from: https://www.npmjs.com/package/@crosscopy/clipboard

Installation

npm i @johnlindquist/clipboard

Usage

It has a very easy to use event-based system.

See demo.ts for a demo.

Run ts-node demo.ts.

import clipboardEventListener from "./@crosscopy/clipboard";

console.log(clipboard.readTextSync());
  console.log(await clipboard.readText());
  const imgBuf = clipboard.readImageSync();
  // console.log(imgBuf.toString("base64"));
  // console.log(clipboard.readImageBase64Sync());
  // await clipboard.writeImage(base64img); // add fake image to clipboard
  clipboard.writeImageSync(base64img); // add fake image to clipboard
  console.log(""); // give some time
  console.assert(clipboard.readImageBase64Sync() === base64img);

  // * test readimage
  clipboard.writeImageSync(base64img);
  console.log();
  console.assert(
    (await clipboard.readImage()).toString("base64") === base64img
  );

  await clipboard.writeImage(base64img);
  console.log();
  console.assert((await clipboard.readImageBase64()) === base64img);
  clipboard.on("text", (text) => {
    console.log(text);
  });
  clipboard.on("image", (data) => {
    fs.writeFileSync("test.png", data);
  });
  clipboard.listen();
  setTimeout(() => {
    clipboard.close();
  }, 10000);

Explanation

It's achieved using child process + stdout.

I took a golang version of the listener from golang-design/clipboard.

When a change is detected, IMAGE_CHANGED or TEXT_CHANGED is printed to stdout.

This library runs compiled go-version clipboard listener using child process and listen to the stdout.

If it sees the keywords in child process's stdout, an event will be emitted.

Run npm run demo to see a demo for 10 sec. Once started, copy some text and screenshot and check the terminal.

Supported Platforms

Format: process.platform/process.arch

The process here is from nodejs.

Supported platforms can be found in go-clipboard/binaries.

If your nodejs gives different platform or arch, it may not work.

Release

Cross Compile doesn't work due to some CGO problem. Have to build on different platforms manually.

Within go-clipboard folder.

go build -o binaries/go-clipboard-darwin-arm64
go build -o binaries/go-clipboard-darwin-x64
go build -o binaries/go-clipboard-win32-x64.exe
go build -o binaries/go-clipboard-linux-x64
go build -o binaries/go-clipboard-linux-arm
go build -o binaries/go-clipboard-linux-arm64