-
Notifications
You must be signed in to change notification settings - Fork 278
API Overrides
- ✅ 2.1 | ✅ 2.0 | ⛔ 1.9 | ...
QZ Tray 2.0 is bundled with RSVP to provide ECMAScript 6 Promise support. If RSVP is not desired, it can be overridden using qz.api.setPromiseType(...)
to avoid ReferenceError: RSVP is not defined
or Uncaught TypeError: Cannot read property 'promise' of null
. Override examples are provided below.
QZ Tray 2.1 will use native promises and an internal sha256 hashing and require no additional dependencies.
- Override RSVP with native Promises using
qz.api.setPromiseType(...)
.
qz.api.setPromiseType(function promise(resolver) { return new Promise(resolver); });
- Include the new promise library:
<script type="text/javascript" src="https://cdn.jsdelivr.net/bluebird/latest/bluebird.js"></script>
or via npm :
npm install bluebird
- Override RSVP with Bluebird using
qz.api.setPromiseType(...)
.
// var Promise = require('bluebird');
qz.api.setPromiseType(function promise(resolver) { return new Promise(resolver); });
- Include the new promise library:
<script type="text/javascript" src="https://rawgit.com/kriskowal/q/v1/q.js"></script>
or via npm :
npm install q
- Override RSVP with Q using
qz.api.setPromiseType(...)
.
var Q = require('q');
qz.api.setPromiseType(Q.Promise);
Keep RSVP, but use it through a framework that doesn't pollute the global namespace:
var RSVP = require('rsvp');
qz.api.setPromiseType(function promise(resolver) { return new RSVP.Promise(resolver); });
As of Node 6.5, WebSockets are only available through 3rd party libraries causing Error: WebSocket not supported by this browser
.
var WebSocket = require('ws'); // require('websocket').w3cwebsocket
qz.api.setWebSocketType(WebSocket);
A hashing algorithm is required for signature validation. Use qz.api.setSha256Type(...)
to override the default hashing library and avoid TypeError: _qz.tools.hash is not a function
.
Since QZ Tray 2.0.5, the native browser crypto
can be used. This will only work with HTTPS pages.
qz.api.setSha256Type(function(data) {
return crypto.createHash('sha256').update(data).digest('hex');
});
-
2.0.1
and older only. Newer versions include this logic by default.
- Requires
sha.js
var createHash = require('sha.js');
qz.api.setSha256Type(function(data) {
return createHash('sha256').update(data).digest('hex');
});
import * as sha256 from 'js-sha256';
qz.api.setSha256Type(function(data) { return sha256(data); });
Install dependencies:
npm install qz-tray ws q
Provide API overrides and start talking to QZ Tray:
var qz = require('qz-tray');
qz.api.setPromiseType(require('q').Promise);
qz.api.setWebSocketType(require('ws'));
qz.websocket.connect()
.then(qz.printers.getDefault)
.then(function(printer) {
console.log("The default printer is: " + printer);
})
.then(qz.websocket.disconnect)
.then(function() {
process.exit(0);
})
.catch(function(err) {
console.error(err);
process.exit(1);
});
This is only for the API overrides. To set up signing, see assets/signing/sign-message.ts
.
Install dependencies:
npm install qz-tray
Provide API overrides and start talking to QZ Tray:
import * as qz from 'qz-tray';
qz.websocket.connect()
.then(qz.printers.getDefault)
.then(printer => console.log("The default printer is: " + printer))
.then(qz.websocket.disconnect)
.catch(err => console.error(err));
Note, Angular 9 and higher will error with the following:
- ERROR in ./node_modules/qz-tray/qz-tray.js
- Module not found: Error: Can't resolve 'path' in 'node_modules/qz-tray'
Add the following entry to your package.json
to omit path
from AOT compilation:
"browser": { "path": false }
QZ Tray 2.0
npm install js-sha256
import { sha256 } from 'js-sha256'; // QZ Tray 2.0 and older
qz.api.setSha256Type(data => sha256(data)); // QZ Tray 2.0 and older
qz.api.setPromiseType(resolver => new Promise(resolver)); // QZ Tray 2.0 and older
</details.