Add templating feature for datetime and counter

Signed-off-by: DL6ER <[email protected]>

Author: DL6ER

app/labeldesigner/label.py

@@ -4,6 +4,8 @@
 import logging
 import barcode
 from barcode.writer import ImageWriter
+import datetime
+import re
 
 logger = logging.getLogger(__name__)
 
@@ -82,7 +84,8 @@ def __init__(
             border_thickness=1,
             border_roundness=0,
             border_distance=(0, 0),
-            border_color=(0, 0, 0)):
+            border_color=(0, 0, 0),
+            timestamp=0):
         self._width = width
         self._height = height
         self.label_content = label_content
@@ -100,6 +103,8 @@ def __init__(
         self._border_roundness = border_roundness
         self._border_distance = border_distance
         self._border_color = border_color
+        self._counter = 1
+        self._timestamp = timestamp
 
     @property
     def label_content(self):
@@ -343,6 +348,22 @@ def _draw_text(self, img = None, bboxes = [], text_offset = (0, 0)):
         # Fix for completely empty text
         if len(self.text) == 0 or len(self.text[0]['text']) == 0:
             self.text[0]['text'] = " "
+            
+        # Loop over text lines and replace
+        # {{datetime:x}} by current datetime in specified format x
+        # {{counter}} by an incrementing counter
+        for line in self.text:
+            line['text'] = line['text'].replace("{{counter}}", str(self._counter))
+            # Replace {{datetime:x}} with current datetime formatted as x
+            def datetime_replacer(match):
+                fmt = match.group(1)
+                if self._timestamp > 0:
+                    now = datetime.datetime.fromtimestamp(self._timestamp)
+                else:
+                    now = datetime.datetime.now()
+                return now.strftime(fmt)
+            line['text'] = re.sub(r"\{\{datetime:([^}]+)\}\}", datetime_replacer, line['text'])
+        self._counter += 1
 
         # Iterate over lines of text
         for i, line in enumerate(self.text):

app/labeldesigner/routes.py

@@ -188,6 +188,7 @@ def create_label_from_request(request):
         'image_bw_threshold': int(d.get('image_bw_threshold', 70)),
         'image_fit': int(d.get('image_fit', 1)) > 0,
         'print_color': d.get('print_color', 'black'),
+        'timestamp': int(d.get('timestamp', 0))
     }
 
     def get_label_dimensions(label_size):
@@ -299,5 +300,6 @@ def get_uploaded_image(image):
         border_thickness=context['border_thickness'],
         border_roundness=context['border_roundness'],
         border_distance=(context['border_distanceX'], context['border_distanceY']),
-        border_color=border_color
+        border_color=border_color,
+        timestamp=context['timestamp']
     )

tests/test_labeldesigner_api.py

@@ -1,5 +1,6 @@
 
 
+from datetime import datetime
 import json
 import sys
 import os
@@ -11,7 +12,7 @@
 UPDATE_IMAGES = False
 EXAMPLE_FORMDATA = {
     'print_type': 'text',
-    'label_size': '62',
+    'label_size': 62,
     'orientation': 'standard',
     'print_count': '1',
     'cut_once': '0',
@@ -331,6 +332,50 @@ def test_image_red_and_black_fit(client):
 def test_image_black_fit(client):
     image_test(client, image_mode="black", fit=True)
 
+
+def test_generate_datetime(client):
+    data = EXAMPLE_FORMDATA.copy()
+    # Mock current datetime.now
+    data['timestamp'] = int(datetime(2023, 1, 1, 12, 0, 0).timestamp())
+
+    data['text'] = json.dumps([
+        {
+            'font_family': 'DejaVu Sans',
+            'font_style': 'Regular',
+            'text': '{{datetime:%d.%m.%Y %H:%M:%S}}',
+            'font_size': '30',
+            'align': 'left'
+        }
+    ])
+
+    response = client.post('/labeldesigner/api/preview', data=data)
+    assert response.status_code == 200
+    assert response.content_type in ['image/png', 'text/plain']
+
+    # Check image
+    verify_image(response.data, 'tests/datetime.png')
+
+
+def test_generate_counter(client):
+    data = EXAMPLE_FORMDATA.copy()
+    data['text'] = json.dumps([
+        {
+            'font_family': 'DejaVu Sans',
+            'font_style': 'Regular',
+            'text': '{{counter}}',
+            'font_size': '60',
+            'align': 'left'
+        }
+    ])
+
+    response = client.post('/labeldesigner/api/preview', data=data)
+    assert response.status_code == 200
+    assert response.content_type in ['image/png', 'text/plain']
+
+    # Check image
+    verify_image(response.data, 'tests/counter.png')
+
+
 # We cannot test the print functionality without a physical printer
 # def test_print_label(client):
 #    data = {