Create label image for container

container/templates/container/container_detail.html

@@ -20,7 +20,7 @@
 <div class="row">
 
   <div class="col-sm-12">
-    <a class="btn btn-primary" href="{% url 'container:edit' container.id %}" role="button">Edit</a>
+    <a class="btn btn-primary" href="{% url 'container:update' container.id %}" role="button">Edit</a>
     <a class="btn btn-primary" href="{% url 'container:delete' container.id %}" role="button">Delete</a>
   </div>
 

container/templates/container/container_list.html

@@ -29,7 +29,11 @@
                       <td><div>{{ container.color }}</div></td>
                       <td><div>{{ container.description }}</div></td>
                       <td><div>{{ container.changed_ts | date:'H:i:s d.m.Y' }}</div></td>
-                      <td><a class="btn btn-outline-primary btn-sm" href="{% url 'container:delete' container.id %}" role="button">Delete</a></td>
+                      <td>
+                          <a class="btn btn-outline-primary btn-sm" href="{% url 'container:delete' container.id %}" role="button">Delete</a>
+                          <a class="btn btn-outline-primary btn-sm" href="{% url 'container:detail' container.id %}" role="button">View</a>
+                          <a class="btn btn-outline-primary btn-sm" href="{% url 'container:print_label' container.id %}" role="button">Label</a>
+                      </td>
                   </tr>
               {% endfor %}
           </tbody>

container/templates/container/container_print_label.html

@@ -0,0 +1,22 @@
+{% extends "base.html" %}
+{% load static %}
+
+{% block title %}Container: {{ container.named_id }}{% endblock %}
+
+{% block content %}
+===== Print Label Content =====
+
+<!-- Action buttons -->
+<div class="row">
+
+  <div class="col-sm-12">
+    Label created for container {{ container.named_id }} of type {{ container.container_type.named_id }}
+    <br />
+    <img  class="img-fluid shadow p-3 mb-5 bg-body rounded" src="{{ barcode_img }}">
+  </div>
+
+</div>
+<!-- End Action buttons -->
+
+</div>
+{% endblock content %}

container/urls.py

@@ -1,13 +1,15 @@
 from django.urls import path
 
-from container.views import ContainerListView, ContainerUpdateView, ContainerCreateView, ContainerDetailView, ContainerDeleteView
+from container.views import ContainerListView, ContainerUpdateView, ContainerCreateView, ContainerDetailView, ContainerDeleteView, ContainerPrintLabelView
 from container.views import ContainerTypeListView, ContainerTypeDetailView, ContainerTypeCreateView, ContainerTypeUpdateView, ContainerTypeDeleteView
 
 app_name = 'container'
 urlpatterns = [
     path('', ContainerListView.as_view(), name='list'),
+    path('<int:pk>/', ContainerDetailView.as_view(), name='detail'),
     path('add/', ContainerCreateView.as_view(), name='add'),
     path('edit/<int:pk>/', ContainerUpdateView.as_view(), name='update'),
+    path('label/<int:pk>/', ContainerPrintLabelView.as_view(), name='print_label'),
     path('delete/<int:pk>/', ContainerDeleteView.as_view(), name='delete'),
     path('type/', ContainerTypeListView.as_view(), name='container_type_list'),
     path('type/<int:pk>/', ContainerTypeDetailView.as_view(), name='container_type_detail'),

container/views.py

@@ -1,6 +1,7 @@
 from django.views import generic
 from .models import Container, ContainerType
-from blabel import LabelWriter
+from labelprinter.labels import container_label
+
 
 class ContainerListView(generic.ListView):
     model = Container
@@ -48,13 +49,36 @@ class ContainerPrintLabelView(generic.DetailView):
     model = Container
     template_name = 'container/container_print_label.html'
 
-    def get(self, **kwargs):
+    def get(self, request, **kwargs):
-        super().get(kwargs)
+        context = super().get(request, **kwargs)
+        '''
         label_writer = LabelWriter(
-            'templates/label/container_label.html',
+            "container/templates/label/container_label.html",
-            default_stylesheets=("templates/label/label_style.css",)
+            default_stylesheets=("container/templates/label/label_style.css",)
         )
-        label_writer.write_labels(kwargs['pk'], target="container_label.pdf")
+        label_writer.write_labels([dict(named_id=kwargs['pk'], id=kwargs['pk'])], target="container_label.pdf")
+        '''
+        return context
+
+    def get_context_data(self, **kwargs):
+        context = super().get_context_data(**kwargs)
+        from labelprinter.labels import container_label
+        container_description = self.object.container_type.named_id
+        if len(self.object.container_type.description) > 0:
+            container_description += ': ' + self.object.container_type.description
+        if len(self.object.description) > 0:
+            container_description += ' / ' + self.object.description
+        context['barcode_img'] = container_label(self.object.named_id, description=container_description, writer_options={'background': 'white',
+                                                                               'font_size': 10,
+                                                                               'foreground': 'black',
+                                                                               'module_height': 10.0,
+                                                                               'module_width': 0.2,
+                                                                               'quiet_zone': 2.5,
+                                                                               'text': 'This is the text',
+                                                                               'text_distance': 3.0,
+                                                                               'write_text': True
+                                                                               })
+        return context
 
 
 class ContainerTypeListView(generic.ListView):
@@ -101,4 +125,3 @@ class ContainerTypeUpdateView(generic.UpdateView):
 
 class ContainerTypeDeleteView(generic.DetailView):
     model = ContainerType
-

labelprinter/labels.py

@@ -0,0 +1,121 @@
+"""Utilities for label generation.
+   stolen from: https://github.com/Edinburgh-Genome-Foundry/blabel
+"""
+import base64
+from io import BytesIO
+import datetime
+import textwrap
+from math import floor
+import barcode as python_barcode
+from PIL import Image, ImageDraw, ImageFont
+
+
+def now(fmt="%Y-%m-%d %H:%M"):
+    """Display the current time.
+    Default format is "year-month-day hour:minute" but another format can be
+    provided (see ``datetime`` docs for date formatting).
+    """
+    now = datetime.datetime.now()
+    if fmt is not None:
+        now = now.strftime(fmt)
+    return now
+
+
+def pil_to_html_imgdata(img, fmt='PNG'):
+    """Convert a PIL image into HTML-displayable data.
+
+    The result is a string ``data:image/FMT;base64,xxxxxxxxx`` which you
+    can provide as a "src" parameter to a ``<img/>`` tag.
+    Examples:
+    ---------
+    >>> data = pil_to_html_imgdata(my_pil_img)
+    >>> html_data = '<img src="%s"/>' % data
+    """
+    buffered = BytesIO()
+    img.save(buffered, format=fmt)
+    img_str = base64.b64encode(buffered.getvalue())
+    prefix = 'data:image/%s;charset=utf-8;base64,' % fmt.lower()
+    return prefix + img_str.decode()
+
+
+def wrap(text, col_width):
+    """Breaks the text into lines with at maximum 'col_width' characters."""
+    return "\n".join(textwrap.wrap(text, col_width))
+
+
+def container_label(data, barcode_class='code128', fmt='png', logo_file='./static/images/djlogo256.png',owner_name='Dirk Jahnke', description='', **writer_options):
+    """Return a barcode's image data.
+    Powered by the Python library ``python-barcode``. See this library's
+    documentation for more details.
+    Parameters
+    ----------
+    data
+      Data to be encoded in the datamatrix.
+    barcode_class
+      Class/standard to use to encode the data. Different standards have
+      different constraints.
+    fmt
+        The format to be used when rendering the resulting image
+        png -> png image
+        svg -> embeddable code for html img tag
+    logo_file
+        File path to logo file to be included
+    writer_options
+      Various options for the writer to tune the appearance of the barcode
+      (see python-barcode documentation).
+    Returns
+    -------
+    image_base64_data
+      A string ``data:image/png;base64,xxxxxxxxx`` which you can provide as a
+      "src" parameter to a ``<img/>`` tag.
+    Examples:
+    ---------
+    >>> data = barcode('EGF12134', barcode_class='code128')
+    >>> html_data = '<img src="%s"/>' % data
+    Examples of writer options:
+    >>> { 'background': 'white',
+    >>>   'font_size': 10,
+    >>>   'foreground': 'black',
+    >>>   'module_height': 15.0,
+    >>>   'module_width': 0.2,
+    >>>   'quiet_zone': 6.5,
+    >>>   'text': '',
+    >>>   'text_distance': 5.0,
+    >>>   'write_text': True
+    >>> }
+    """
+
+    with Image.open(logo_file) as logo_img:
+        font_size = 16
+        logo_img = logo_img.resize((128,128))
+        logo_img = logo_img.convert('L')
+        threshold = 20
+        logo_img = logo_img.point(lambda p: 255 if p < threshold else 0)
+        logo_img = logo_img.convert('1')
+        constructor = python_barcode.get_barcode_class(barcode_class)
+        data = str(data).zfill(constructor.digits)
+        writer = {
+            'svg': python_barcode.writer.ImageWriter,
+            'png': python_barcode.writer.ImageWriter
+        }[fmt]
+        barcode_img = constructor(data, writer=writer())
+        img = barcode_img.render(writer_options=writer_options)
+        barcode_xsize, barcode_ysize = img.size
+        logo_xsize, logo_ysize = logo_img.size
+        result_img = Image.new('1', (696, barcode_ysize+20), 1)
+        result_img.paste(logo_img, (0, floor(barcode_ysize/3)-floor(logo_ysize/2)))
+        start_x_for_barcode = logo_xsize + 10
+        max_x_for_barcode = 696 - start_x_for_barcode
+        result_img.paste(img, (start_x_for_barcode + floor((max_x_for_barcode-barcode_xsize)/2), 5))
+        # fnt = ImageFont.truetype("Pillow/Tests/fonts/FreeMono.ttf", 40)
+        fnt = ImageFont.truetype("./static/fonts/DejaVuSerif.ttf", font_size)
+
+        d = ImageDraw.Draw(result_img)
+        d.text((20,logo_ysize+40), owner_name, font=fnt)
+        d.text((30+floor((660-fnt.getlength(description))/2),barcode_ysize), description, font=fnt)
+
+        if fmt == 'png':
+            return pil_to_html_imgdata(result_img, fmt='PNG')
+        else:
+            prefix = "data:image/svg+xml;charset=utf-8;base64,"
+            return prefix + base64.b64encode(result_img).decode()