Added encryption for note contents

Author: OmkarPathak

README.md

@@ -10,6 +10,7 @@ A pretty easy django notes app. Have a note save it!
 - Easily share
 - Download note as PDF
 - Beautiful yet simple UI
+- Encrypted Data so that no one can phish it! ([using django-cryptography](https://github.com/georgemarshall/django-cryptography))
 
 # Installation
 

notekeeper/notes/migrations/0005_auto_20200222_0823.py

@@ -0,0 +1,72 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+from django_cryptography.fields import encrypt
+
+app_with_model = 'notes'
+model_with_column = 'Note'
+column_to_encrypt = 'note_content'
+column_field_class = models.TextField
+column_attrs = {}
+column_null_status = True
+temporary_column = f'temp_{column_to_encrypt}'
+
+def replicate_to_temporary(apps, schema_editor):
+    Model = apps.get_model(app_with_model, model_with_column)
+    for row in Model.objects.all():
+        setattr(row, temporary_column, getattr(row, column_to_encrypt, None))
+        setattr(row, column_to_encrypt, None)
+        row.save(update_fields=[temporary_column, column_to_encrypt])
+
+def replicate_to_real(apps, schema_editor):
+    Model = apps.get_model(app_with_model, model_with_column)
+    for row in Model.objects.all():
+        setattr(row, column_to_encrypt, getattr(row, temporary_column))
+        row.save(update_fields=[column_to_encrypt])
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('notes', '0004_auto_20191202_1919'),
+    ]
+
+    operations = [
+        # create temporary column
+        migrations.AddField(
+            model_name=model_with_column.lower(),
+            name=temporary_column,
+            field=column_field_class(
+                verbose_name=temporary_column, null=True, **column_attrs),
+        ),
+        # allow null entries in the real column
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=column_field_class(
+                verbose_name=column_to_encrypt, null=True, **column_attrs),
+        ),
+        # push all data from real to temporary
+        migrations.RunPython(replicate_to_temporary),
+        # encrypt the real column (still allowing null values)
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=encrypt(column_field_class(
+                verbose_name=column_to_encrypt, null=True, **column_attrs)),
+        ),
+        # push all data from temporary to real (encrypting in the processes)
+        migrations.RunPython(replicate_to_real),
+        # remove the temporary column
+        migrations.RemoveField(
+            model_name=model_with_column.lower(),
+            name=temporary_column),
+        # disallow null values (if applicable)
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=encrypt(column_field_class(
+                verbose_name=column_to_encrypt, null=column_null_status, 
+                **column_attrs)),
+        ),
+    ]

notekeeper/notes/migrations/0006_auto_20200222_0837.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.2.7 on 2020-02-22 03:07
+
+from django.db import migrations, models
+import django_cryptography.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('notes', '0005_auto_20200222_0823'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='note',
+            name='note_content',
+            field=django_cryptography.fields.encrypt(models.TextField(blank=True, null=True)),
+        ),
+    ]

notekeeper/notes/migrations/0007_auto_20200222_0845.py

@@ -0,0 +1,72 @@
+# Generated by Django 2.2.7 on 2020-02-22 03:15
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+from django_cryptography.fields import encrypt
+
+app_with_model = 'notes'
+model_with_column = 'Note'
+column_to_encrypt = 'note_content'
+column_field_class = models.TextField
+column_attrs = {}
+column_null_status = True
+temporary_column = f'temp_{column_to_encrypt}'
+
+def replicate_to_temporary(apps, schema_editor):
+    Model = apps.get_model(app_with_model, model_with_column)
+    for row in Model.objects.all():
+        setattr(row, temporary_column, getattr(row, column_to_encrypt, None))
+        setattr(row, column_to_encrypt, None)
+        row.save(update_fields=[temporary_column, column_to_encrypt])
+
+def replicate_to_real(apps, schema_editor):
+    Model = apps.get_model(app_with_model, model_with_column)
+    for row in Model.objects.all():
+        setattr(row, column_to_encrypt, getattr(row, temporary_column))
+        row.save(update_fields=[column_to_encrypt])
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('notes', '0006_auto_20200222_0837'),
+    ]
+
+    operations = [
+        # create temporary column
+        migrations.AddField(
+            model_name=model_with_column.lower(),
+            name=temporary_column,
+            field=column_field_class(
+                verbose_name=temporary_column, null=True, **column_attrs),
+        ),
+        # allow null entries in the real column
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=column_field_class(
+                verbose_name=column_to_encrypt, null=True, **column_attrs),
+        ),
+        # push all data from real to temporary
+        migrations.RunPython(replicate_to_temporary),
+        # encrypt the real column (still allowing null values)
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=encrypt(column_field_class(
+                verbose_name=column_to_encrypt, null=True, **column_attrs)),
+        ),
+        # push all data from temporary to real (encrypting in the processes)
+        migrations.RunPython(replicate_to_real),
+        # remove the temporary column
+        migrations.RemoveField(
+            model_name=model_with_column.lower(),
+            name=temporary_column),
+        # disallow null values (if applicable)
+        migrations.AlterField(
+            model_name=model_with_column.lower(),
+            name=column_to_encrypt,
+            field=encrypt(column_field_class(
+                verbose_name=column_to_encrypt, null=column_null_status, 
+                **column_attrs)),
+        ),
+    ]

notekeeper/notes/models.py

@@ -14,6 +14,7 @@
 import markdown.extensions.codehilite
 import markdown.extensions.tables
 import markdown.extensions.toc
+from django_cryptography.fields import encrypt
 
 
 def generate_unique_slug(_class, field):
@@ -34,7 +35,7 @@ def generate_unique_slug(_class, field):
 class Note(models.Model):
     user = models.ForeignKey(User, on_delete=models.CASCADE)
     note_title = models.CharField(max_length=200)
-    note_content = models.TextField(null=True, blank=True)
+    note_content = encrypt(models.TextField(null=True, blank=True))
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
     slug = models.SlugField(max_length=200, unique=True)

requirements.txt

@@ -16,3 +16,4 @@ xhtml2pdf==0.2.3
 Markdown==3.1.1
 Unidecode==1.1.1
 markdown-checklist==0.4.1
+django-cryptography==1.0