Added Attachment model

fmartingrcom/apps/blog/admin.py

@@ -1,5 +1,5 @@
 from django.contrib import admin
-from .models import Entry, Tag
+from .models import Entry, Tag, Attachment
 from ckeditor.widgets import CKEditorWidget
 from django.utils.translation import ugettext as _
 from reversion.admin import VersionAdmin
@@ -15,6 +15,7 @@ class EntryAdminForm(forms.ModelForm):
         model = Entry
         fields = ('title', 'slug', 'draft', 'date', 'tags', 'content')
 
+
 #
 #   ENTRY
 #
@@ -80,3 +81,12 @@ class TagAdmin(VersionAdmin):
     pass
 
 admin.site.register(Tag, TagAdmin)
+
+
+#
+#    ATTACHMENT
+#
+class AttachmentAdmin(VersionAdmin):
+    pass
+
+admin.site.register(Attachment, AttachmentAdmin)

fmartingrcom/apps/blog/migrations/0003_attachment.py

@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.4 on 2016-03-21 19:29
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import fmartingrcom.apps.blog.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('blog', '0002_auto_20160313_1051'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Attachment',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('filename', models.CharField(max_length=256)),
+                ('sha1', models.CharField(max_length=40)),
+                ('mimetype', models.CharField(blank=True, max_length=256, null=True)),
+                ('file', models.FileField(upload_to=fmartingrcom.apps.blog.models.attachment_upload_to)),
+                ('creation_date', models.DateTimeField(auto_now_add=True)),
+                ('modification_date', models.DateTimeField(auto_now=True)),
+            ],
+            options={
+                'verbose_name': 'Attachment',
+            },
+        ),
+    ]

fmartingrcom/apps/blog/models.py

@@ -1,12 +1,26 @@
 # -*- coding: utf-8 -*-
 from datetime import datetime
+import logging
+import mimetypes
+import os
+import re
+import shutil
+import subprocess
 
 from django.db import models
 from django.conf import settings
+from django.core.files import File
 from django.utils.timezone import utc
 from django.core.urlresolvers import reverse
+from django.dispatch.dispatcher import receiver
+from django.db.models.signals import pre_delete
+
+from fmartingrcom.utils import sha1_checksum
+
 import mistune
 
+logger = logging.getLogger()
+
 
 #
 #   ENTRY
@@ -76,3 +90,106 @@ class Tag(models.Model):
     class Meta:
         app_label = 'blog'
         ordering = ['name']
+
+
+#
+#   ATTACHMENT
+#
+def attachment_upload_to(instance, filename):
+    return os.path.join('{}_.{}'.format(
+        instance.media_path, instance.extension
+    ))
+
+
+class Attachment(models.Model):
+    filename = models.CharField(max_length=256)
+    sha1 = models.CharField(max_length=40)
+    mimetype = models.CharField(max_length=256, blank=True, null=True)
+    file = models.FileField(upload_to=attachment_upload_to)
+
+    creation_date = models.DateTimeField(auto_now_add=True)
+    modification_date = models.DateTimeField(auto_now=True)
+
+    @property
+    def extension(self):
+        return self.file.url.split('.')[-1]
+
+    @property
+    def url(self):
+        return self.file.url
+
+    @property
+    def media_path(self):
+        p1 = self.sha1[0:2]
+        p2 = self.sha1[2:4]
+        return 'attachment/{}/{}/{}/'.format(p1, p2, self.sha1)
+
+    @staticmethod
+    def upload_file(handler, filename=None):
+        """
+        Given a certain file handler returns an `Image` objects
+        handler can be:
+        + django.core.files.File instance __or subclass of__ (UploadedFile)
+        + string with an absolute path to an image
+        """
+        FLAGS = 'rw+'
+
+        # File Path
+        if isinstance(handler, str):
+            f = File(open(handler, FLAGS))
+        elif issubclass(handler.__class__, File) or isinstance(handler, File):
+            # Re-read with correct flags
+            f = handler
+            f.mode = FLAGS
+        else:
+            # I give up!
+            f = handler
+
+        if not filename:
+            filename = f.name.split('/')[-1]
+
+        sha1 = sha1_checksum(f)
+
+        # Check if file exists
+        try:
+            obj = Attachment.objects.get(sha1=sha1)
+        except Attachment.DoesNotExist:
+            obj = Attachment()
+            obj.file = f
+            obj.sha1 = sha1
+            obj.filename = filename
+            obj.mimetype = Attachment.get_mimetype(f, obj.filename)
+            obj.save()
+
+        return obj
+
+    @staticmethod
+    def get_mimetype(handler, filename):
+        re_mime_validate = re.compile('\w+/\w+(; \w+=[^;]+)*')
+
+        # subprocess
+        p = subprocess.Popen(('file', '--brief', '--mime-type', '-'),
+                             stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+        stdout, stderr = p.communicate(handler.read())
+        if re_mime_validate.match(stdout):
+            mimetype = stdout.split()[0]
+        else:
+            # by python
+            mime, encoding = mimetypes.guess_type(filename)
+            mimetype = mime if mime else None
+
+            # rewind file descriptor
+            handler.file.seek(0)
+
+        return mimetype
+
+    class Meta:
+        verbose_name = 'Attachment'
+
+
+@receiver(pre_delete, sender=Attachment)
+def clean_files_on_delete(sender, instance, **kwargs):
+    try:
+        shutil.rmtree('/'.join(instance.file.path.split('/')[:-1]))
+    except Exception as error:
+        logger.warning(error, exc_info=True)

fmartingrcom/utils.py

@@ -0,0 +1,8 @@
+# -*- coding: utf-8 -*-
+import hashlib
+
+
+def sha1_checksum(handler):
+    f = open(handler.file.name, 'rb')
+    checksum = hashlib.sha1(f.read())
+    return checksum.hexdigest()