Added GPG encryption for the PDFs

src/documents/admin.py

@@ -1,5 +1,5 @@
-from django.conf import settings
 from django.contrib import admin
+from django.core.urlresolvers import reverse
 from django.templatetags.static import static
 
 from .models import Document
@@ -8,27 +8,20 @@ from .models import Document
 class DocumentAdmin(admin.ModelAdmin):
 
     search_fields = ("sender", "title", "content",)
-    list_display = ("edit", "created", "sender", "title", "thumbnail", "pdf")
+    list_display = ("edit", "created", "sender", "title", "pdf")
     list_filter = ("created", "sender")
     save_on_top = True
 
     def edit(self, obj):
-        return '<img src="{}" width="64" height="64" alt="Edit icon" />'.format(
+        return '<img src="{}" width="22" height="22" alt="Edit icon" />'.format(
             static("documents/img/edit.png"))
     edit.allow_tags = True
 
-    def thumbnail(self, obj):
-        return '<a href="{media}documents/img/{pk:07}.jpg" target="_blank">' \
-                 '<img src="{media}documents/img/{pk:07}.jpg" width="100" />' \
-               '</a>'.format(media=settings.MEDIA_URL, pk=obj.pk)
-    thumbnail.allow_tags = True
-
     def pdf(self, obj):
-        return '<a href="{}documents/pdf/{:07}.pdf">' \
-                 '<img src="{}" width="64" height="64" alt="PDF icon">' \
+        return '<a href="{}">' \
+                 '<img src="{}" width="22" height="22" alt="PDF icon">' \
                '</a>'.format(
-                    settings.MEDIA_URL,
-                    obj.pk,
+                    reverse("fetch", kwargs={"pk": obj.pk}),
                     static("documents/img/application-pdf.png")
                 )
     pdf.allow_tags = True

src/documents/management/commands/consume.py

@@ -1,9 +1,9 @@
 import datetime
 import glob
+import gnupg
 import os
 import random
 import re
-import shutil
 import subprocess
 import time
 
@@ -36,8 +36,6 @@ class Command(BaseCommand):
     CONSUME = settings.CONSUMPTION_DIR
 
     OCR = pyocr.get_available_tools()[0]
-
-    MEDIA_IMG = os.path.join(settings.MEDIA_ROOT, "documents", "img")
     MEDIA_PDF = os.path.join(settings.MEDIA_ROOT, "documents", "pdf")
 
     PARSER_REGEX = re.compile(r"^.*/(.*) - (.*)\.pdf$")
@@ -45,6 +43,7 @@ class Command(BaseCommand):
     def __init__(self, *args, **kwargs):
         self.verbosity = 0
         self.stats = {}
+        self.gpg = gnupg.GPG(gnupghome=settings.GNUPG_HOME)
         BaseCommand.__init__(self, *args, **kwargs)
 
     def handle(self, *args, **options):
@@ -77,18 +76,16 @@ class Command(BaseCommand):
             if self._is_ready(pdf):
                 continue
 
-            if self.verbosity > 1:
-                print("Consuming {}".format(pdf))
+            self._render("Consuming {}".format(pdf), 1)
 
             pngs = self._get_greyscale(pdf)
-            jpgs = self._get_colour(pdf)
             text = self._get_ocr(pngs)
 
-            self._store(text, jpgs, pdf)
-            self._cleanup(pngs, jpgs)
+            self._store(text, pdf)
+            self._cleanup(pngs, pdf)
 
     def _setup(self):
-        for d in (self.SCRATCH, self.MEDIA_IMG, self.MEDIA_PDF):
+        for d in (self.SCRATCH, self.MEDIA_PDF):
             try:
                 os.makedirs(d)
             except FileExistsError:
@@ -112,7 +109,9 @@ class Command(BaseCommand):
 
     def _get_greyscale(self, pdf):
 
-        i = random.randint(1000000, 4999999)
+        self._render("  Generating greyscale image", 2)
+
+        i = random.randint(1000000, 9999999)
         png = os.path.join(self.SCRATCH, "{}.png".format(i))
 
         subprocess.Popen((
@@ -122,45 +121,46 @@ class Command(BaseCommand):
 
         return sorted(glob.glob(os.path.join(self.SCRATCH, "{}*".format(i))))
 
-    def _get_colour(self, pdf):
-
-        i = random.randint(5000000, 9999999)
-        jpg = os.path.join(self.SCRATCH, "{}.jpg".format(i))
-
-        subprocess.Popen((self.CONVERT, pdf, jpg)).wait()
-
-        return sorted(glob.glob(os.path.join(self.SCRATCH, "{}*".format(i))))
-
     def _get_ocr(self, pngs):
 
+        self._render("  OCRing the PDF", 2)
+
         r = ""
         for png in pngs:
             with Image.open(os.path.join(self.SCRATCH, png)) as f:
+                self._render("    {}".format(f.filename), 3)
                 r += self.OCR.image_to_string(f)
                 r += "\n\n\n\n\n\n\n\n"
 
         return r
 
-    def _store(self, text, jpgs, pdf):
+    def _store(self, text, pdf):
 
         sender, title = self._parse_file_name(pdf)
 
         stats = os.stat(pdf)
 
+        self._render("  Saving record to database", 2)
+
         doc = Document.objects.create(
             sender=sender,
             title=title,
             content=text,
             created=timezone.make_aware(
-                    datetime.datetime.fromtimestamp(stats.st_ctime)),
-                modified=timezone.make_aware(
                 datetime.datetime.fromtimestamp(stats.st_mtime)),
+            modified=timezone.make_aware(
+                datetime.datetime.fromtimestamp(stats.st_mtime))
         )
 
-        shutil.move(jpgs[0], os.path.join(
-            self.MEDIA_IMG, "{:07}.jpg".format(doc.pk)))
-        shutil.move(pdf, os.path.join(
-            self.MEDIA_PDF, "{:07}.pdf".format(doc.pk)))
+        with open(pdf, "rb") as unencrypted:
+            with open(doc.pdf_path, "wb") as encrypted:
+                self._render("  Encrypting", 3)
+                encrypted.write(self.gpg.encrypt_file(
+                    unencrypted,
+                    recipients=None,
+                    passphrase=settings.PASSPHRASE,
+                    symmetric=True
+                ).data)
 
     def _parse_file_name(self, pdf):
         """
@@ -175,12 +175,15 @@ class Command(BaseCommand):
 
         return "", ""
 
-    def _cleanup(self, pngs, jpgs):
+    def _cleanup(self, pngs, pdf):
 
-        jpg_glob = os.path.join(
-            self.SCRATCH, re.sub(r"^.*/(\d+)-\d+.jpg$", "\\1*", jpgs[0]))
         png_glob = os.path.join(
             self.SCRATCH, re.sub(r"^.*/(\d+)-\d+.png$", "\\1*", pngs[0]))
 
-        for f in list(glob.glob(jpg_glob)) + list(glob.glob(png_glob)):
+        for f in list(glob.glob(png_glob)) + [pdf]:
+            self._render("  Deleting {}".format(f), 2)
             os.unlink(f)
+
+    def _render(self, text, verbosity):
+        if self.verbosity >= verbosity:
+            print(text)

src/documents/models.py

@@ -1,3 +1,6 @@
+import os
+
+from django.conf import settings
 from django.db import models
 from django.utils import timezone
 
@@ -20,3 +23,16 @@ class Document(models.Model):
         if self.sender or self.title:
             return "{}: {}, {}".format(created, self.sender or self.title)
         return str(created)
+
+    @property
+    def pdf_path(self):
+        return os.path.join(
+            settings.MEDIA_ROOT,
+            "documents",
+            "pdf",
+            "{:07}.pdf.gpg".format(self.pk)
+        )
+
+    @property
+    def pdf(self):
+        return open(self.pdf_path, "rb")

src/documents/views.py

@@ -1,3 +1,29 @@
-from django.shortcuts import render
+import gnupg
 
-# Create your views here.
+from django.conf import settings
+from django.http import HttpResponse
+from django.template.defaultfilters import slugify
+from django.views.generic.detail import DetailView
+
+from .models import Document
+
+
+class PdfView(DetailView):
+
+    model = Document
+
+    def render_to_response(self, context, **response_kwargs):
+        """
+        Override the default to return the unencrypted PDF as raw data.
+        """
+
+        gpg = gnupg.GPG(gnupghome=settings.GNUPG_HOME)
+
+        response = HttpResponse(gpg.decrypt_file(
+            self.object.pdf,
+            passphrase=settings.PASSPHRASE,
+        ).data, content_type="application/pdf")
+        response["Content-Disposition"] = 'attachment; filename="{}"'.format(
+            slugify(str(self.object)) + ".pdf")
+
+        return response

src/manage.py

@@ -5,6 +5,15 @@ import sys
 if __name__ == "__main__":
     os.environ.setdefault("DJANGO_SETTINGS_MODULE", "paperless.settings")
 
+    from django.conf import settings
     from django.core.management import execute_from_command_line
 
+    # The runserver and consumer need to have access to the passphrase, so it
+    # must be entered at start time to keep it safe.
+    if "runserver" in sys.argv or "consume" in sys.argv:
+        settings.PASSPHRASE = "asdf"
+        if not settings.DEBUG:
+            settings.PASSPHRASE = input(
+                "Production environment.  Input passphrase: ")
+
     execute_from_command_line(sys.argv)

src/paperless/requirements.txt

@@ -0,0 +1,4 @@
+Django==1.9
+Pillow==3.0.0
+pyocr==0.3.1
+python-gnupg==0.3.8

src/paperless/settings.py

@@ -135,3 +135,5 @@ MEDIA_URL = "/media/"
 CONVERT_BINARY = "/usr/bin/convert"
 SCRATCH_DIR = "/tmp/paperless"  # Will be created if it doesn't exist
 CONSUMPTION_DIR = "/tmp/paperless/consume"
+GNUPG_HOME = os.environ.get("HOME", "/dev/null")
+PASSPHRASE = None  # Set via manage.py

src/paperless/urls.py

@@ -18,6 +18,9 @@ from django.conf import settings
 from django.conf.urls import url, static
 from django.contrib import admin
 
+from documents.views import PdfView
+
 urlpatterns = [
+    url(r"^fetch/(?P<pk>\d+)$", PdfView.as_view(), name="fetch"),
     url(r'', admin.site.urls),
 ] + static.static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)