From 991025d13ed246f941db0b70faf5a92a107cb701 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sascha=20I=C3=9Fbr=C3=BCcker?= <sissbruecker@lyska.io>
Date: Thu, 26 Dec 2019 13:45:12 +0100
Subject: [PATCH] Implement bookmark export

---
 bookmarks/services/exporter.py          | 44 +++++++++++++++++++++++++
 bookmarks/templates/settings/index.html |  9 ++++-
 bookmarks/urls.py                       |  1 +
 bookmarks/views/settings.py             | 23 +++++++++++--
 4 files changed, 74 insertions(+), 3 deletions(-)
 create mode 100644 bookmarks/services/exporter.py

diff --git a/bookmarks/services/exporter.py b/bookmarks/services/exporter.py
new file mode 100644
index 0000000..459b6fe
--- /dev/null
+++ b/bookmarks/services/exporter.py
@@ -0,0 +1,44 @@
+from typing import List
+
+from bookmarks.models import Bookmark
+
+BookmarkDocument = List[str]
+
+
+def export_netscape_html(bookmarks: List[Bookmark]):
+    doc = []
+    append_header(doc)
+    append_list_start(doc)
+    [append_bookmark(doc, bookmark) for bookmark in bookmarks]
+    append_list_end(doc)
+
+    return '\n\r'.join(doc)
+
+
+def append_header(doc: BookmarkDocument):
+    doc.append('<!DOCTYPE NETSCAPE-Bookmark-file-1>')
+    doc.append('<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=UTF-8">')
+    doc.append('<TITLE>Bookmarks</TITLE>')
+    doc.append('<H1>Bookmarks</H1>')
+
+
+def append_list_start(doc: BookmarkDocument):
+    doc.append('<DL><p>')
+
+
+def append_bookmark(doc: BookmarkDocument, bookmark: Bookmark):
+    url = bookmark.url
+    title = bookmark.resolved_title
+    desc = bookmark.resolved_description
+    tags = ','.join(bookmark.tag_names)
+    toread = '1' if bookmark.unread else '0'
+    added = int(bookmark.date_added.timestamp())
+
+    doc.append(f'<DT><A HREF="{url}" ADD_DATE="{added}" PRIVATE="0" TOREAD="{toread}" TAGS="{tags}">{title}</A>')
+
+    if desc:
+        doc.append(f'<DD>{desc}')
+
+
+def append_list_end(doc: BookmarkDocument):
+    doc.append('</DL><p>')
diff --git a/bookmarks/templates/settings/index.html b/bookmarks/templates/settings/index.html
index 150dbd1..30950b5 100644
--- a/bookmarks/templates/settings/index.html
+++ b/bookmarks/templates/settings/index.html
@@ -39,7 +39,14 @@
                 <h2>Export</h2>
             </div>
             <p>Export all bookmarks in Netscape HTML format.</p>
-            <a class="btn btn-primary">Download (.html)</a>
+            <a class="btn btn-primary" href="{% url 'bookmarks:settings.export' %}">Download (.html)</a>
+            {% if export_error %}
+                <div class="has-error">
+                    <p class="form-input-hint">
+                        {{ export_error }}
+                    </p>
+                </div>
+            {% endif %}
         </section>
 
     </div>
diff --git a/bookmarks/urls.py b/bookmarks/urls.py
index 7244a18..90b8487 100644
--- a/bookmarks/urls.py
+++ b/bookmarks/urls.py
@@ -18,6 +18,7 @@ urlpatterns = [
     # Settings
     path('settings', views.settings.index, name='settings.index'),
     path('settings/import', views.settings.bookmark_import, name='settings.import'),
+    path('settings/export', views.settings.bookmark_export, name='settings.export'),
     # API
     path('api/website_metadata', views.api.website_metadata, name='api.website_metadata'),
 ]
diff --git a/bookmarks/views/settings.py b/bookmarks/views/settings.py
index e7bbf3d..d9552cc 100644
--- a/bookmarks/views/settings.py
+++ b/bookmarks/views/settings.py
@@ -1,9 +1,11 @@
 from django.contrib import messages
 from django.contrib.auth.decorators import login_required
-from django.http import HttpResponseRedirect
+from django.http import HttpResponseRedirect, HttpResponse
 from django.shortcuts import render
 from django.urls import reverse
 
+from bookmarks.models import Bookmark
+from bookmarks.services.exporter import export_netscape_html
 from bookmarks.services.importer import import_netscape_html
 
 
@@ -22,13 +24,30 @@ def bookmark_import(request):
         content = import_file.read()
         import_netscape_html(content, request.user)
         messages.success(request, 'Bookmarks were successfully imported.', 'bookmark_import')
-    except():
+    except Exception:
         messages.error(request, 'An error occurred during bookmark import.', 'bookmark_import')
         pass
 
     return HttpResponseRedirect(reverse('bookmarks:settings.index'))
 
 
+@login_required
+def bookmark_export(request):
+    try:
+        bookmarks = Bookmark.objects.all()
+        file_content = export_netscape_html(bookmarks)
+
+        response = HttpResponse(content_type='text/plain; charset=UTF-8')
+        response['Content-Disposition'] = 'attachment; filename="bookmarks.html"'
+        response.write(file_content)
+
+        return response
+    except Exception:
+        return render(request, 'settings/index.html', {
+            'export_error': 'An error occurred during bookmark export.'
+        })
+
+
 def _find_message_with_tag(messages, tag):
     for message in messages:
         if message.extra_tags == tag: