If on Mac:
another_square is a Flutter package for the Square REST APIs.
Supports all Flutter supported platforms:
Install another_square
flutter pub add another_square
Important: Because of the way Square handles their developer portal at the time of this writing it's not possible to access the sandbox endpoint from mobile. The production endpoints however work fine. So this means that during development it's recommended to use another platform like Web for testing.
With your developer account information at hand we can now move on to configuring the Square client and be able to make requests to the Square REST APIs.
// IMPORTANT: When trying to access the sandbox oauth in Square
// through the mobile device it fails to get past "To start OAuth flow
// for a sandbox account." So for development using the sandbox it's
// recommended to user an auth token directly and bypass the OAuth flow.
// For Production that problem doesn't happen.
// Found in https://developer.squareup.com/apps/
final String applicationId = <application id>;
final String clientId = <application id>;
final String clientSecret = <application secrete>;
// Configured in Square Dashboard.
final String redirectUrl =
"https://localhost";
squareClient = SquareClient(
applicationId: applicationId,
clientId: clientId,
clientSecret: clientSecret,
environmentType: EnvironmentType.Sandbox);
await squareClient!.initialize();
Once the client is configured we can obtain the auth URL to authenticate the app with our Square account.
authUrl = squareClient!.getAuthorizationPageUrl(
scopes: [Scope.OrdersRead, Scope.OrdersWrite],
redirectUrl: redirectUrl,
state: "state123");
When we complete the OAth2 flow we can then use the client to get the authorization token as follows:
Future<void> requestAccessToken(String code) async {
token = await squareClient!.getAuthToken(code: code,
redirectUrl: redirectUrl,
);
setState(() {
});
}
With the client configured and the app authorized we can proceed to make requests to the Square APIs. In this example we'll create an order receipt which will then print on a Brother printer.
Create the order on Square:
//////////////////////////////////////////////////
/// Create an order
//////////////////////////////////////////////////
var createdOrd = await squareClient!.createOrder(
//authToken: authToken,
request: CreateOrderRequest.fromJson({
"idempotency_key": "C8193148c-9586-11e6-99f9-28cfe92138cf",
"order": {
"reference_id": "my-order-001",
"location_id": "LPYKKD4HSCRGP", //"LZM0BVPKR59NK",
"line_items": [
{
"name": "New York Strip Steak",
"quantity": "1",
"base_price_money": {
"amount": 1599,
"currency": "USD"
}
},
{
"name": "Oranges",
"quantity": "2",
"base_price_money": {
"amount": 1599,
"currency": "USD"
}
},
{
"name": "Other Item",
"quantity": "2",
"base_price_money": {
"amount": 999,
"currency": "USD"
}
},
],
"taxes": [
{
"uid": "state-sales-tax",
"name": "State Sales Tax",
"percentage": "9",
"scope": "ORDER"
}
],
}
}));
With the order created, we'll then convert it to an image in order to be able to print it on the Brother printer.
//////////////////////////////////////////////////
/// Convert order to Image
//////////////////////////////////////////////////
ui.Image imageToPrint = await _generateReceipt(createdOrd);
receiptPreview = await _getWidgetImage(createdOrd);
Bonus: Helper method for turning the Square order into an image.
Future<ui.Image> _generateReceipt(Order order) async {
ui.PictureRecorder recorder = ui.PictureRecorder();
Canvas canvas = Canvas(recorder);
double baseSize = 200;
double labelWidthPx = 9 * baseSize;
//double labelHeightPx = 3 * baseSize;
//double qrSizePx = labelHeightPx / 2;
// Start Padding of the QR Code
double qrPaddingStart = 30;
// Start Padding of the Paragraph in relation to the QR Code
double paraPaddingStart = 30;
// Font Size for largest text
double primaryFontSize = 100;
// Create Paragraph
ui.ParagraphBuilder paraBuilder = ui.ParagraphBuilder(new ui.ParagraphStyle(textAlign: TextAlign.start));
order.lineItems?.forEach((lineItem) {
// Add heading to paragraph
paraBuilder.pushStyle(ui.TextStyle(fontSize: primaryFontSize, color: Colors.black, fontWeight: FontWeight.bold));
paraBuilder.addText("${lineItem.name} x ${lineItem.quantity}\t\t \$${(lineItem.totalMoney!.amount!)/100.0}\n");
paraBuilder.pop();
});
paraBuilder.pushStyle(ui.TextStyle(fontSize: primaryFontSize, color: Colors.black, fontWeight: FontWeight.bold));
paraBuilder.addText("\nTotal: \$${order.totalMoney!.amount!/100.0}");
paraBuilder.pop();
Offset paraOffset = Offset.zero;
ui.Paragraph infoPara = paraBuilder.build();
// Layout the pargraph in the remaining space.
infoPara.layout(ui.ParagraphConstraints(width: labelWidthPx));
Paint paint = new Paint();
paint.color = Color.fromRGBO(255, 255, 255, 1);
Rect bounds = new Rect.fromLTWH(0, 0, labelWidthPx, infoPara.height);
canvas.save();
canvas.drawRect(bounds, paint);
// Draw paragrpah on canvas.
canvas.drawParagraph(infoPara, paraOffset);
var picture = await recorder.endRecording().toImage(9 * 200, 3 * 200);
return picture;
}
In order to print we'll first need to define what printer we are going to print on, what label (or paper) the printer has and what channel of communication we'll use to send the print request to the printer.
The another_brother plugin allows for a large level of detail when specifing your print. In this section however we'll just present the most basic setup to get you printing.
The snippet below shows how to print to a 1110NWB printer with a W103 label (103mm wide) talking over Bluetooth Classic.
var printer = new Printer();
var printInfo = PrinterInfo();
printInfo.printerModel = Model.QL_1110NWB;
printInfo.printMode = PrintMode.FIT_TO_PAGE;
printInfo.isAutoCut = true;
printInfo.port = Port.BLUETOOTH;
// Set the label type.
printInfo.labelNameIndex = QL1100.ordinalFromID(QL1100.W103.getId());
// Set the printer info so we can use the SDK to get the printers.
await printer.setPrinterInfo(printInfo);
With the printer configured we then need to find a specific printer to connect to by looking for a list of printers bonded to the device. In this example we are connecting over Bluetooth but similar methods exist WiFi.
List<BluetoothPrinter> printers = await printer.getBluetoothPrinters([Model.QL_1110NWB.getName()]);
Since at this point we are not interested in any specific printer we'll just grab the first one and print to it.
printInfo.macAddress = printers.single.macAddress;
printer.setPrinterInfo(printInfo);
And last but not least we'll print an image from our assets folder.
With the printer configured and the receipt ready all that remains is to send the file to the Brother printer for printing.
// Print Invoice
PrinterStatus status = await printer.printImage(imageToPrint);