Printing to POS printer from PHP

We are looking to print to a POS printer connected where apache is running. Due to design of the application, and deployment, printing should be done from Server (it should detect the order and send to different printers and different formats of printing...bill, kitchen orders, and so on...). For this reason and others (like access application from an iPad for example) we discard options like QZ-Print applet and needst o print directly server side.

We searched a lot, and found that there are an extension called php-printer but seems outdated, and just works under WIndows.

We followed this code: (http://mocopat.wordpress.com/2012/01/18/php-direct-printing-printer-dot-matrix-lx-300/)

$tmpdir = sys_get_temp_dir();   # ambil direktori temporary untuk simpan file.
$file =  tempnam($tmpdir, 'ctk');  # nama file temporary yang akan dicetak
$handle = fopen($file, 'w');
$condensed = Chr(27) . Chr(33) . Chr(4);
$bold1 = Chr(27) . Chr(69);
$bold0 = Chr(27) . Chr(70);
$initialized = chr(27).chr(64);
$condensed1 = chr(15);
$condensed0 = chr(18);
$corte = Chr(27) . Chr(109);
$Data  = $initialized;
$Data .= $condensed1;
$Data .= "==========================\n";
$Data .= "|     ".$bold1."OFIDZ MAJEZTY".$bold0."      |\n";
$Data .= "==========================\n";
$Data .= "Ofidz Majezty is here\n";
$Data .= "We Love PHP Indonesia\n";
$Data .= "We Love PHP Indonesia\n";
$Data .= "We Love PHP Indonesia\n";
$Data .= "We Love PHP Indonesia\n";
$Data .= "We Love PHP Indonesia\n";
$Data .= "--------------------------\n";
$Data .= $corte;
fwrite($handle, $Data);
fclose($handle);
copy($file, "//localhost/KoTickets");  # Lakukan cetak
unlink($file);

And it works, but this sends plain text, and we need to send image (logo), and format a more cute bill. We tried creating a PDF and "sending" to the printer in the same way, but just prints blank.

I found a library to work with network printers (escpos-php on github), but we need to work with USB printers too, to avoid our customers to change hardware.

Some ideas how to achieve this?

Thanks in advance.

Solution

Author of escpos-php here.

If your printers do support ESC/POS (most thermal receipt printers seem to use some sub-set of it), then I think the driver will accommodate your use case: USB or network printing, logo, some formatting. Some of these are quite recent additions.

USB printing

escpos-php prints to a file pointer. On Linux, you can make the USB printer visible as a a file using the usblp driver, and then just fopen() it (USB receipt example, blog post about installing a USB printer on Linux).

So printing "Hello world" on a USB printer is only slightly different to printing to a networked printer:

<?php
require __DIR__ . '/vendor/autoload.php';
use Mike42\Escpos\PrintConnectors\FilePrintConnector;
use Mike42\Escpos\Printer;
$connector = new FilePrintConnector("/dev/usb/lp0");
$printer = new Printer($connector);

$printer -> text("Hello World!\n");
$printer -> cut();

$printer -> close();

Or, more like the code you are currently using successfully, you could write to a temp file and copy it:

<?php
require __DIR__ . '/vendor/autoload.php';
use Mike42\Escpos\PrintConnectors\FilePrintConnector;
use Mike42\Escpos\Printer;

/* Open file */
$tmpdir = sys_get_temp_dir();
$file =  tempnam($tmpdir, 'ctk');

/* Do some printing */
$connector = new FilePrintConnector($file);
$printer = new Printer($connector);
$printer -> text("Hello World!\n");
$printer -> cut();

$printer -> close();

/* Copy it over to the printer */
copy($file, "//localhost/KoTickets");
unlink($file);

So in your POS system, you would need a function which returns a file pointer based on your customer configuration and preferred destination. Receipt printers respond quite quickly, but if you have a few iPads making orders, you should wrap operations to each printer with a file lock (flock()) to avoid concurrency-related trouble.

Also note that USB support on Windows is un-tested.

Logo & Formatting

Once you have figured out how you plan to talk to the printer, you can use the full suite of formatting and image commands.

A logo can be printed from a PNG file like so:

use Mike42\Escpos\EscposImage;
$logo = EscposImage::load("foo.png");
$printer -> graphics($logo);

And for formatting, the README.md and the example below should get you started. For most receipts, you only really need:

selectPrintMode() to alter font sizes.
setEmphasis() to toggle bold.
setJustification() to left-align or center some text or images.
cut() after each receipt.

I would also suggest that where you are currently using an example that draws boxes like this:

=========
|       |
=========

You could make use of the characters in IBM Code page 437 which are designed for drawing boxes that are supported by many printers- just include characters 0xB3 to 0xDA in the output. They aren't perfect, but it looks a lot less "text"-y.

$box = "\xda".str_repeat("\xc4", 10)."\xbf\n";
$box .= "\xb3".str_repeat(" ", 10)."\xb3\n";
$box .= "\xc0".str_repeat("\xc4", 10)."\xd9\n";
$printer -> textRaw($box);

Full example

The below example is also now included with the driver. I think it looks like a fairly typical store receipt, formatting-wise, and could be easily adapted to your kitchen scenario.

Scanned output:

Example formatted receipt including logo

PHP source code to generate it:

<?php
require __DIR__ . '/vendor/autoload.php';
use Mike42\Escpos\Printer;
use Mike42\Escpos\EscposImage;
use Mike42\Escpos\PrintConnectors\FilePrintConnector;

/* Open the printer; this will change depending on how it is connected */
$connector = new FilePrintConnector("/dev/usb/lp0");
$printer = new Printer($connector);

/* Information for the receipt */
$items = array(
    new item("Example item #1", "4.00"),
    new item("Another thing", "3.50"),
    new item("Something else", "1.00"),
    new item("A final item", "4.45"),
);
$subtotal = new item('Subtotal', '12.95');
$tax = new item('A local tax', '1.30');
$total = new item('Total', '14.25', true);
/* Date is kept the same for testing */
// $date = date('l jS \of F Y h:i:s A');
$date = "Monday 6th of April 2015 02:56:25 PM";

/* Start the printer */
$logo = EscposImage::load("resources/escpos-php.png", false);
$printer = new Printer($connector);

/* Print top logo */
$printer -> setJustification(Printer::JUSTIFY_CENTER);
$printer -> graphics($logo);

/* Name of shop */
$printer -> selectPrintMode(Printer::MODE_DOUBLE_WIDTH);
$printer -> text("ExampleMart Ltd.\n");
$printer -> selectPrintMode();
$printer -> text("Shop No. 42.\n");
$printer -> feed();

/* Title of receipt */
$printer -> setEmphasis(true);
$printer -> text("SALES INVOICE\n");
$printer -> setEmphasis(false);

/* Items */
$printer -> setJustification(Printer::JUSTIFY_LEFT);
$printer -> setEmphasis(true);
$printer -> text(new item('', '$'));
$printer -> setEmphasis(false);
foreach ($items as $item) {
    $printer -> text($item);
}
$printer -> setEmphasis(true);
$printer -> text($subtotal);
$printer -> setEmphasis(false);
$printer -> feed();

/* Tax and total */
$printer -> text($tax);
$printer -> selectPrintMode(Printer::MODE_DOUBLE_WIDTH);
$printer -> text($total);
$printer -> selectPrintMode();

/* Footer */
$printer -> feed(2);
$printer -> setJustification(Printer::JUSTIFY_CENTER);
$printer -> text("Thank you for shopping at ExampleMart\n");
$printer -> text("For trading hours, please visit example.com\n");
$printer -> feed(2);
$printer -> text($date . "\n");

/* Cut the receipt and open the cash drawer */
$printer -> cut();
$printer -> pulse();

$printer -> close();

/* A wrapper to do organise item names & prices into columns */
class item
{
    private $name;
    private $price;
    private $dollarSign;

    public function __construct($name = '', $price = '', $dollarSign = false)
    {
        $this -> name = $name;
        $this -> price = $price;
        $this -> dollarSign = $dollarSign;
    }

    public function __toString()
    {
        $rightCols = 10;
        $leftCols = 38;
        if ($this -> dollarSign) {
            $leftCols = $leftCols / 2 - $rightCols / 2;
        }
        $left = str_pad($this -> name, $leftCols) ;

        $sign = ($this -> dollarSign ? '$ ' : '');
        $right = str_pad($sign . $this -> price, $rightCols, ' ', STR_PAD_LEFT);
        return "$left$right\n";
    }
}