NW-Autoupdater v1.1

Library provides low-level API to control NW.js app auto-updates. This project can be seen as a reincarnation of node-webkit-updater, which is not maintained anymore.

Features

• Node >= 7 compliant
• clean async/await syntax
• supports both Zip/Tar.Gz archives
• fires download/install progress events

Strategy ScriptSwap

📹 Screencast: Running nw-autoupdater examples in the terminal on Ubuntu

What do we do to autoupdate (see demo A or demo B)

• readRemoteManifest reads manifest from the remote release server
• checkNewVersion( rManifest ) checks if the version in the remote manifest greater than one of the local manifest
• If the remote manifest doesn't have newer version, skips the update flow
  • We subscribe for download events
  • We subscribe for install events
• download( rManifest ) downloads the latest available release matching the host platform (according to the packages map of the remote manifest)
• unpack( updateFile ) unpacks the release archive (zip or tar.gz) in a temporary directory
• Strategy AppSwap
  • restartToSwap( extraArgs ) closes the app and launches the downloaded release
  • isSwapRequest() - checks if we need to go the swap flow (while running in tmp and therefore having the initial app directory unlocked for writing)
  • swap() - backs up actual version and replaces it with the new one
  • restart( extraArgs ) - restarts the updated app from its original location
• Strategy ScriptSwap
  • restartToSwap() closes the app and launches the swap script, which launches the application when it's done

Distribution

• Run release server (see example)
• Add to your client manifest (package.json) field manifestUrl pointing at release server
• Package your app by using nwjs-builder (see example)
• Update the contents of packages field in release server manifest (e.g. by running node update.js)
• Update version field in release server manifest
• Launch your app and observe it's auto-updating

Examples

• Client/Strategy AppSwap
• Client/Strategy ScriptSwap
• Server

API

Constructor

new AutoUpdate( manifest, options );

Params

• manifest - e.g. require( "./package.json" )
• options.strategy - (OPTIONAL) can be ScriptSwap or AppSwap. By default AppSwap
• options.executable - (OPTIONAL) executable if it doesn't match project name
• options.backupDir - (OPTIONAL) directory to backup. By default it's .bak next to app directory
• options.execDir - (OPTIONAL) app directory. By default it's extracted from process.execPath (nwjs-builder bundles the app into self-extractable and process.cwd() is not a reliable source). Yet on a Mac process.execPath contains the full path to the executable within MacOS bundle. So you rather use this option to set the app path directly.
• options.updateDir - (OPTIONAL) temporary directory where the downloaded package gets extracted. By default /tmp/nw-autoupdater
• options.logPath - (OPTIONAL) the full path to the log file. By default nw.App.dataPath + "/nw-autoupdater.log": Windows: %LOCALAPPDATA%/; Linux: ~/.config/; OSX: ~/Library/Application Support/
• options.verbose - (OPTIONAL) when true swap script reports verbose in the log file. By default false
• options.swapScript - (OPTIONAL) you custom swap script content (NOTE: available only for ScriptSwap strategy)
• options.accumulativeBackup - (OPTIONAL) when true for every backup creates a new folder. By default false

Writing custom swap script

You can define with options.swapScript you own custom swap script:

 const updater = new AutoUpdater( require( "./package.json" ), {
          strategy: "ScriptSwap",
          swapScript: `
BASH/BAT SCRIPT CONTENT
`
      });

By default on Linux/MacIO the following script is used:

rsync -a\${VERBOSE} --delete \${APP_PATH}/. \${BAK_PATH}/
rsync -a\${VERBOSE} --delete \${UPDATE_PATH}/. \${APP_PATH}/

where the variables are populated from ARGV:

• VERBOSE - "v" or ""
• APP_PATH - application home directory
• BAK_PATH - backup directory
• UPDATE_PATH - update directory

For example, if you have for package not the entire NW.js application, but just HTML5 project, you set up the following script:

rsync -a\${VERBOSE} --delete \${APP_PATH}/. \${BAK_PATH}/
rsync -a\${VERBOSE} \${UPDATE_PATH}/. \${APP_PATH}/package

So it backups the project, but copies extracted packaged into package subfolder in application home directory

readRemoteManifest

Reads package.json of the release server

const rManifest = await updater.readRemoteManifest();

Returns: Promise

checkNewVersion

Check if the release server has newer app version

const needsUpdate = await updater.checkNewVersion( rManifest );

Params

• rManifest - manifest of the release server

Returns: Promise

download

Download last available update to the temp directory

const updateFile = await updater.download( rManifest, { debounceTime: 100 });

Params

• rManifest - manifest of the release server
• options.debounceTime - (OPTIONAL) debounce time in milliseconds

Returns: Promise

unpack

Unpack downloaded update

const extractDir = await updater.unpack( updateFile, { debounceTime: 100 } );

Params

• updateFile - path to downloaded update
• options.debounceTime - (OPTIONAL) debounce time in milliseconds

Returns: Promise

restartToSwap

Close this version of app and start the downloaded one with --swap param

await updater.restartToSwap();

Params

• extraArgs - (OPTIONAL) Extra arguments to be passed to the newly started app

Returns: Promise

Events

download

Subscribe on download progress event

updater.on( "download", ( downloadSize, totalSize ) => {
  console.log( "download progress", Math.floor( downloadSize / totalSize * 100 ), "%" );
});

install

Subscribe on install progress event

updater.on( "install", ( installFiles, totalFiles ) => {
  console.log( "install progress", Math.floor( installFiles / totalFiles * 100 ), "%" );
});

Extra Methods required for Strategy AppSwap

isSwapRequest

Checks if the app launched for swap

const needsSwap = updater.isSwapRequest();

Returns: boolean

swap

Backs up current version of the app and replaces it with the downloaded version

await updater.swap();

Returns: Promise

restart

Restarts the updated app

await updater.restart();

Params

• extraArgs - (OPTIONAL) Extra arguments to be passed to the newly started app

Returns: Promise

Contributing

nw-autoupdater welcomes maintainers. There is plenty of work to do. No big commitment required, if all you do is review a single Pull Request, you are a maintainer.

How to check changes

# Clone the git repo
git clone git@github.com:dsheiko/nw-autoupdater.git

# Navigate to the newly created directory
cd nw-autoupdater

# Switch the branch if needed
# Make changes in the code
# Bundle the package
npm pack

# You'will get a new file like `nw-autoupdater-1.1.11.tgz`
# Switch a client example
cd example/client-strategy-script/

# Install the updated package
npm i ../../nw-autoupdater-1.1.11.tgz

# Package demo app
npm run package

# Extract demo app package in a temp directory
unzip ../server/releases/nw-autoupdater-demo-r1.0.0-linux-x64.zip -d /tmp/Sandbox/

# Switch to release server example
cd ../server/
# Make sure dependencies up to date
npm i
# Update releases manifest
npm run update
# Start the server
npm start

# Now start the demo app from your temp /tmp/Sandbox/
/tmp/Sandbox/nw-autoupdater-demo

# It says:
#  Application ver. 1.0.0
#  App is up to date...

# Switch back to demo app and update its version
cd ../client-strategy-script/
npm version patch
npm run package

# Back to the server to update manifest
cd ../server/
npm run update
npm start

# When starting the built app it updates
/tmp/Sandbox/nw-autoupdater-demo

---

My book:

Cross-platform Desktop Application Development: Electron, Node, NW.js, and React

I split the book in four tutorials, starting with basics and advancing progressively though more and more complex aspects. So the first part guides on creating a file-explorer built with pure JavaScript and NW.js/Node.js. The second part is about creating a chat with Electron, React and PhotonKit. The third part is about screen capturer made with NW.js, React/Redux and Material UI. The last part guides on creating RSS aggregator with Electron, React, Redux and TypeScript.