Added support for multiple printers

Fixed runtime errors (on osx)

brother_ql_web.py

@@ -1,4 +1,5 @@
 #!/usr/bin/env python
+# -*- coding: utf-8 -*-
 
 """
 This is a web service to print labels on Brother QL label printers.
@@ -21,6 +22,8 @@ logger = logging.getLogger(__name__)
 
 LABEL_SIZES = [ (name, label_type_specs[name]['name']) for name in label_sizes]
 
+PRINTERS = {}
+
 try:
     with open('config.json') as fh:
         CONFIG = json.load(fh)
@@ -45,7 +48,8 @@ def labeldesigner():
             'fonts': FONTS,
             'label_sizes': LABEL_SIZES,
             'website': CONFIG['WEBSITE'],
-            'label': CONFIG['LABEL']}
+            'label': CONFIG['LABEL'],
+            'printers': PRINTERS }
 
 def get_label_context(request):
     """ might raise LookupError() """
@@ -69,6 +73,7 @@ def get_label_context(request):
       'margin_bottom': float(d.get('margin_bottom', 45))/100.,
       'margin_left':   float(d.get('margin_left',   35))/100.,
       'margin_right':  float(d.get('margin_right',  35))/100.,
+      'printer_name':  d.get('printer_name', None),
     }
     context['margin_top']    = int(context['font_size']*context['margin_top'])
     context['margin_bottom'] = int(context['font_size']*context['margin_bottom'])
@@ -179,11 +184,15 @@ def print_text():
     try:
         context = get_label_context(request)
     except LookupError as e:
-        return_dict['error'] = e.msg
+        return_dict['message'] = e.msg
         return return_dict
 
-    if context['text'] is None:
+    if not context['text'] or context['text'] is None:
-        return_dict['error'] = 'Please provide the text for the label'
+        return_dict['message'] = 'Please provide the text for the label'
+        return return_dict
+
+    if not context['printer_name'] or context['printer_name'] is None:
+        return_dict['message'] = 'Please select a printer'
         return return_dict
 
     im = create_label_im(**context)
@@ -194,12 +203,20 @@ def print_text():
     elif context['kind'] in (ROUND_DIE_CUT_LABEL, DIE_CUT_LABEL):
         rotate = 'auto'
     
-    qlr = BrotherQLRaster(CONFIG['PRINTER']['MODEL'])
+    qlr = BrotherQLRaster(PRINTERS[context['printer_name']]["MODEL"])
     create_label(qlr, im, context['label_size'], threshold=context['threshold'], cut=True, rotate=rotate)
 
+    try:
+        selected_backend = guess_backend(PRINTERS[context['printer_name']]["LOCATION"])
+    except Exception as e:
+        return_dict['message'] = str(e)
+        return return_dict
+    
+    BACKEND_CLASS = backend_factory(selected_backend)['backend_class']
+
     if not DEBUG:
         try:
-            be = BACKEND_CLASS(CONFIG['PRINTER']['PRINTER'])
+            be = BACKEND_CLASS(PRINTERS[context['printer_name']]["LOCATION"])
             be.write(qlr.data)
             be.dispose()
             del be
@@ -219,13 +236,13 @@ def main():
     parser.add_argument('--loglevel', type=lambda x: getattr(logging, x.upper()), default=False)
     parser.add_argument('--font-folder', default=False, help='folder for additional .ttf/.otf fonts')
     parser.add_argument('--default-label-size', default=False, help='Label size inserted in your printer. Defaults to 62.')
-    parser.add_argument('--default-orientation', default=False, choices=('standard', 'rotated'), help='Label orientation, defaults to "standard". To turn your text by 90°, state "rotated".')
+    parser.add_argument('--default-orientation', default=False, choices=('standard', 'rotated'), help='Label orientation, defaults to "standard". To turn your text by 90 degrees, state "rotated".')
     parser.add_argument('--model', default=False, choices=models, help='The model of your printer (default: QL-500)')
     parser.add_argument('printer',  nargs='?', default=False, help='String descriptor for the printer to use (like tcp://192.168.0.23:9100 or file:///dev/usb/lp0)')
     args = parser.parse_args()
 
     if args.printer:
-        CONFIG['PRINTER']['PRINTER'] = args.printer
+        CONFIG['PRINTERS']['PRINTER'] = args.printer
 
     if args.port:
         PORT = args.port
@@ -243,7 +260,7 @@ def main():
         DEBUG = False
 
     if args.model:
-        CONFIG['PRINTER']['MODEL'] = args.model
+        CONFIG['PRINTERS']['MODEL'] = args.model
 
     if args.default_label_size:
         CONFIG['LABEL']['DEFAULT_SIZE'] = args.default_label_size
@@ -259,12 +276,6 @@ def main():
 
     logging.basicConfig(level=LOGLEVEL)
 
-    try:
-        selected_backend = guess_backend(CONFIG['PRINTER']['PRINTER'])
-    except ValueError:
-        parser.error("Couln't guess the backend to use from the printer string descriptor")
-    BACKEND_CLASS = backend_factory(selected_backend)['backend_class']
-
     if CONFIG['LABEL']['DEFAULT_SIZE'] not in label_sizes:
         parser.error("Invalid --default-label-size. Please choose on of the following:\n:" + " ".join(label_sizes))
 
@@ -290,6 +301,9 @@ def main():
         CONFIG['LABEL']['DEFAULT_FONTS'] = {'family': family, 'style': style}
         sys.stderr.write('The default font is now set to: {family} ({style})\n'.format(**CONFIG['LABEL']['DEFAULT_FONTS']))
 
+    for printer in CONFIG['PRINTERS']:
+        PRINTERS[printer["NAME"]] = printer
+
     run(host=CONFIG['SERVER']['HOST'], port=PORT, debug=DEBUG)
 
 if __name__ == "__main__":

config.example.json

@@ -5,10 +5,13 @@
     "LOGLEVEL": "WARNING",
     "ADDITIONAL_FONT_FOLDER": false
   },
-  "PRINTER": {
+  "PRINTERS": [
-    "MODEL": "QL-500",
+    {
-    "PRINTER": "file:///dev/usb/lp1"
+      "NAME": "Labelprinter",
-  },
+      "MODEL": "QL-500",
+      "LOCATION": "file:///dev/usb/lp1"
+    }
+  ],
   "LABEL": {
     "DEFAULT_SIZE": "62",
     "DEFAULT_ORIENTATION": "standard",

font_helpers.py

@@ -20,6 +20,7 @@ def get_fonts(folder=None):
         if not line: continue
         if 'otf' not in line and 'ttf' not in line: continue
         parts = line.split(':')
+        if len(parts) < 3: continue
         path = parts[0]
         families = parts[1].strip().split(',')
         styles = parts[2].split('=')[1].split(',')

views/labeldesigner.jinja2

@@ -116,6 +116,18 @@
         <label for="previewImg">Label Preview:</label><br />
         <img id="previewImg" style="border: 1px solid #444; max-height: 350px; width: auto; max-width: 100%; margin-bottom: 10px;"/>
         <p>Printed size w/o margins: <span id="labelWidth">?</span> cm x <span id="labelHeight">?</span> cm</p>
+
+        <div {% if printers|length == 1 %} hidden {% endif %}>
+          <label for="printer">Printer:</label>
+          <select class="form-control" id="printer">
+            <option value="" disabled {% if printers|length > 1 %} selected {% endif %} > -- select a printer -- </option>
+            {% for printer in printers %}
+                <option value="{{printer}}" {% if printers|length == 1 %} selected {% endif %} >{{printer}}</option>
+            {% endfor %}
+          </select>
+          <br/>
+        </div>
+        
         <button id="printButton" type="button" class="btn btn-primary btn-block btn-lg" onClick="print()">
           <span class="glyphicon glyphicon-print" aria-hidden="true"></span> Print
         </button>
@@ -136,9 +148,8 @@
 var text = $('#labelText');
 
 function formData() {
-  //var text = $('#labelText').val().replace(/\n/g, "%0A");
   var text = $('#labelText').val();
-  if (text == '') text = ' ';
+  
   return {
     text:        text,
     font_family: $('#fontFamily option:selected').text(),
@@ -149,7 +160,8 @@ function formData() {
     margin_top:    $('#marginTop').val(),
     margin_bottom: $('#marginBottom').val(),
     margin_left:   $('#marginLeft').val(),
-    margin_right:  $('#marginRight').val()
+    margin_right:  $('#marginRight').val(),
+    printer_name:  $('#printer option:selected').val()
   }
 }