Add support for generating a simple Web App Manifest file, which helps mobile browsers display the site smartly

Pipfile

@@ -27,6 +27,7 @@ bleach = "*"
 django-debug-toolbar = "*"
 xrd = "*"
 django-push = "*"
+pyyaml = "*"
 
 
 [dev-packages]

Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "bf80c6036fc124e9afa1aa029b73d614b477dba02cf948696dd8eb1fa50dc745"
+            "sha256": "dc4aa7d01f78e031ce0e169c70b3056b8a436bfc3195126b6a801943ee39e2fb"
         },
         "host-environment-markers": {
             "implementation_name": "cpython",
@@ -344,6 +344,25 @@
             ],
             "version": "==2017.2"
         },
+        "pyyaml": {
+            "hashes": [
+                "sha256:3262c96a1ca437e7e4763e2843746588a965426550f3797a79fca9c6199c431f",
+                "sha256:16b20e970597e051997d90dc2cddc713a2876c47e3d92d59ee198700c5427736",
+                "sha256:e863072cdf4c72eebf179342c94e6989c67185842d9997960b3e69290b2fa269",
+                "sha256:bc6bced57f826ca7cb5125a10b23fd0f2fff3b7c4701d64c439a300ce665fff8",
+                "sha256:c01b880ec30b5a6e6aa67b09a2fe3fb30473008c85cd6a67359a1b15ed6d83a4",
+                "sha256:827dc04b8fa7d07c44de11fabbc888e627fa8293b695e0f99cb544fdfa1bf0d1",
+                "sha256:592766c6303207a20efc445587778322d7f73b161bd994f227adaa341ba212ab",
+                "sha256:5f84523c076ad14ff5e6c037fe1c89a7f73a3e04cf0377cb4d017014976433f3",
+                "sha256:0c507b7f74b3d2dd4d1322ec8a94794927305ab4cebbe89cc47fe5e81541e6e8",
+                "sha256:b4c423ab23291d3945ac61346feeb9a0dc4184999ede5e7c43e1ffb975130ae6",
+                "sha256:ca233c64c6e40eaa6c66ef97058cdc80e8d0157a443655baa1b2966e812807ca",
+                "sha256:4474f8ea030b5127225b8894d626bb66c01cda098d47a2b0d3429b6700af9fd8",
+                "sha256:326420cbb492172dec84b0f65c80942de6cedb5233c413dd824483989c000608",
+                "sha256:5ac82e411044fb129bae5cfbeb3ba626acb2af31a8d17d175004b70862a741a7"
+            ],
+            "version": "==3.12"
+        },
         "qrcode": {
             "hashes": [
                 "sha256:60222a612b83231ed99e6cb36e55311227c395d0d0f62e41bb51ebbb84a9a22b",

lemoncurry/templates/lemoncurry/layout.html

@@ -9,6 +9,7 @@
 
 		<link rel="hub" href="{% get_push_hub %}" />
 		<link rel="self" href="{{ uri }}" />
+		<link rel="manifest" href="{% url 'wellknowns:manifest' %}" />
 
 		<meta property="og:url" content="{{ uri }}" />
 		<meta property="og:title" content="{% firstof title site_name %}" />

lemoncurry/theme.py

@@ -0,0 +1,11 @@
+from django.conf import settings
+from os.path import join
+from yaml import safe_load
+
+path = join(
+    settings.BASE_DIR,
+    'lemoncurry', 'static',
+    'base16-materialtheme-scheme', 'material-darker.yaml',
+)
+with open(path, 'r') as f:
+    theme = safe_load(f)

wellknowns/urls.py

@@ -7,5 +7,6 @@ urlpatterns = [
     url(r'^keybase.txt$', views.keybase, name='keybase'),
     url(r'^host-meta$', views.host_meta_xml, name='host-meta'),
     url(r'^host-meta.json$', views.host_meta_json, name='host-meta.json'),
+    url(r'^manifest.json$', views.manifest, name='manifest'),
     url(r'^webfinger$', views.webfinger, name='webfinger'),
 ]

wellknowns/views/__init__.py

@@ -1,3 +1,4 @@
 from .static import keybase
 from .host_meta import host_meta_xml, host_meta_json
+from .manifest import manifest
 from .webfinger import webfinger

wellknowns/views/manifest.py

@@ -0,0 +1,28 @@
+from django.conf import settings
+from django.http import JsonResponse
+from favicon.models import FaviconImg
+from lemoncurry import utils
+from lemoncurry.theme import theme
+from urllib.parse import urljoin
+
+
+def manifest(request):
+    origin = utils.origin(request)
+    app = {
+        'name': settings.LEMONCURRY_SITE_NAME,
+        'background_color': '#' + theme['base00'],
+        'theme_color': '#' + theme['base02'],
+    }
+
+    rels = ('shortcut icon', 'apple-touch-icon')
+    icons = FaviconImg.objects.filter(
+        faviconFK__isFavicon=True,
+        rel__in=rels,
+    ).order_by('size')
+    app['icons'] = [{
+        'type': 'image/png',
+        'size': '{0}x{0}'.format(icon.size),
+        'src': urljoin(origin, icon.faviconImage.url),
+    } for icon in icons]
+
+    return JsonResponse(app, content_type='application/manifest+json')