[IMP] hw_escpos: get rid of printer whitelist

It makes more sense to just look for usb devices that identify as a
printer and use whatever we get. This saves us time having to explain to
users how to add their particular printer to the whitelist to test.

addons/hw_escpos/controllers/main.py

@@ -52,60 +52,37 @@ class EscposDriver(Thread):
         self.lock  = Lock()
         self.status = {'status':'connecting', 'messages':[]}
 
-    def supported_devices(self):
-        if not os.path.isfile('escpos_devices.pickle'):
-            return supported_devices.device_list
-        else:
-            try:
-                f = open('escpos_devices.pickle','r')
-                return pickle.load(f)
-                f.close()
-            except Exception as e:
-                self.set_status('error',str(e))
-                return supported_devices.device_list
-
-    def add_supported_device(self,device_string):
-        r = re.compile('[0-9A-Fa-f]{4}:[0-9A-Fa-f]{4}');
-        match = r.search(device_string)
-        if match:
-            match = match.group().split(':')
-            vendor = int(match[0],16)
-            product = int(match[1],16)
-            name = device_string.split('ID')
-            if len(name) >= 2:
-                name = name[1]
-            else:
-                name = name[0]
-            _logger.info('ESC/POS: adding support for device: '+match[0]+':'+match[1]+' '+name)
-            
-            device_list = supported_devices.device_list[:]
-            if os.path.isfile('escpos_devices.pickle'):
-                try:
-                    f = open('escpos_devices.pickle','r')
-                    device_list = pickle.load(f)
-                    f.close()
-                except Exception as e:
-                    self.set_status('error',str(e))
-            device_list.append({
-                'vendor': vendor,
-                'product': product,
-                'name': name,
-            })
-
-            try:
-                f = open('escpos_devices.pickle','w+')
-                f.seek(0)
-                pickle.dump(device_list,f)
-                f.close()
-            except Exception as e:
-                self.set_status('error',str(e))
-
     def connected_usb_devices(self):
         connected = []
-        
-        for device in self.supported_devices():
-            if usb.core.find(idVendor=device['vendor'], idProduct=device['product']) != None:
-                connected.append(device)
+
+        # printers can either define bDeviceClass=7, or they can define one of
+        # their interfaces with bInterfaceClass=7. This class checks for both.
+        class FindUsbClass(object):
+            def __init__(self, usb_class):
+                self._class = usb_class
+            def __call__(self, device):
+                # first, let's check the device
+                if device.bDeviceClass == self._class:
+                    return True
+                # transverse all devices and look through their interfaces to
+                # find a matching class
+                for cfg in device:
+                    intf = usb.util.find_descriptor(cfg, bInterfaceClass=self._class)
+
+                    if intf is not None:
+                        return True
+
+                return False
+
+        printers = usb.core.find(find_all=True, custom_match=FindUsbClass(7))
+
+        for printer in printers:
+            connected.append({
+                'vendor': printer.idVendor,
+                'product': printer.idProduct,
+                'name': usb.util.get_string(printer, 256, printer.iManufacturer) + " " + usb.util.get_string(printer, 256, printer.iProduct)
+            })
+
         return connected
 
     def lockedstart(self):
@@ -377,18 +354,3 @@ class EscposProxy(hw_proxy.Proxy):
         _logger.info('ESC/POS: PRINT XML RECEIPT') 
         driver.push_task('xml_receipt',receipt)
 
-    @http.route('/hw_proxy/escpos/add_supported_device', type='http', auth='none', cors='*')
-    def add_supported_device(self, device_string):
-        _logger.info('ESC/POS: ADDED NEW DEVICE:'+device_string) 
-        driver.add_supported_device(device_string)
-        return "The device:\n"+device_string+"\n has been added to the list of supported devices.<br/><a href='/hw_proxy/status'>Ok</a>"
-
-    @http.route('/hw_proxy/escpos/reset_supported_devices', type='http', auth='none', cors='*')
-    def reset_supported_devices(self):
-        try:
-            os.remove('escpos_devices.pickle')
-        except Exception as e:
-            pass
-        return 'The list of supported devices has been reset to factory defaults.<br/><a href="/hw_proxy/status">Ok</a>'
-
-    

addons/hw_escpos/escpos/__init__.py

@@ -1 +1 @@
-__all__ = ["constants","escpos","exceptions","printer","supported_devices"]
+__all__ = ["constants","escpos","exceptions","printer"]

addons/hw_escpos/escpos/supported_devices.py

@@ -1,11 +0,0 @@
-#!/usr/bin/python
-
-# This is a list of esc/pos compatible usb printers. The vendor and product ids can be found by
-# typing lsusb in a linux terminal, this will give you the ids in the form ID VENDOR:PRODUCT
-
-device_list = [
-    { 'vendor' : 0x04b8, 'product' : 0x0e03, 'name' : 'Epson TM-T20' },
-    { 'vendor' : 0x04b8, 'product' : 0x0202, 'name' : 'Epson TM-T70' },
-    { 'vendor' : 0x04b8, 'product' : 0x0e15, 'name' : 'Epson TM-T20II' },
-]
-