Media proxy, caching and tuning docs

Fixes #67

3 files changed, 107 insertions, 0 deletions

diff --git a/mediaproxy/__init__.py b/mediaproxy/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/mediaproxy/__init__.py
diff --git a/mediaproxy/apps.py b/mediaproxy/apps.py
new file mode 100644
index 0000000..6b87719
--- /dev/null
+++ b/mediaproxy/apps.py
@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class MediaproxyConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "mediaproxy"
diff --git a/mediaproxy/views.py b/mediaproxy/views.py
new file mode 100644
index 0000000..e799e8b
--- /dev/null
+++ b/mediaproxy/views.py
@@ -0,0 +1,101 @@
+import httpx
+from django.conf import settings
+from django.core.cache import caches
+from django.http import Http404, HttpResponse
+from django.shortcuts import get_object_or_404
+from django.views.generic import View
+
+from activities.models import PostAttachment
+from users.models import Identity
+
+
+class BaseCacheView(View):
+    """
+    Base class for caching remote content.
+    """
+
+    cache_name = "media"
+    item_timeout: int | None = None
+
+    def get(self, request, **kwargs):
+        self.kwargs = kwargs
+        remote_url = self.get_remote_url()
+        cache = caches[self.cache_name]
+        cache_key = "proxy_" + remote_url
+        # See if it's already cached
+        cached_content = cache.get(cache_key)
+        if not cached_content:
+            # OK, fetch and cache it
+            try:
+                remote_response = httpx.get(
+                    remote_url,
+                    headers={"User-Agent": settings.TAKAHE_USER_AGENT},
+                    follow_redirects=True,
+                    timeout=settings.SETUP.REMOTE_TIMEOUT,
+                )
+            except (httpx.ConnectError, httpx.RequestError):
+                return HttpResponse(status=502)
+            if remote_response.status_code >= 400:
+                return HttpResponse(status=502)
+            # We got it - shove it into the cache
+            cached_content = {
+                "content": remote_response.content,
+                "mimetype": remote_response.headers.get(
+                    "Content-Type", "application/octet-stream"
+                ),
+            }
+            cache.set(cache_key, cached_content, timeout=self.item_timeout)
+        return HttpResponse(
+            cached_content["content"],
+            headers={
+                "Content-Type": cached_content["mimetype"],
+            },
+        )
+
+    def get_remote_url(self):
+        raise NotImplementedError()
+
+
+class IdentityIconCacheView(BaseCacheView):
+    """
+    Caches identity icons (avatars)
+    """
+
+    cache_name = "avatars"
+    item_timeout = 86400 * 7  # One week
+
+    def get_remote_url(self):
+        self.identity = get_object_or_404(Identity, pk=self.kwargs["identity_id"])
+        if self.identity.local or not self.identity.image_uri:
+            raise Http404()
+        return self.identity.icon_uri
+
+
+class IdentityImageCacheView(BaseCacheView):
+    """
+    Caches identity profile header images
+    """
+
+    item_timeout = 86400 * 7  # One week
+
+    def get_remote_url(self):
+        self.identity = get_object_or_404(Identity, pk=self.kwargs["identity_id"])
+        if self.identity.local or not self.identity.image_uri:
+            raise Http404()
+        return self.identity.image_uri
+
+
+class PostAttachmentCacheView(BaseCacheView):
+    """
+    Caches post media (images only, videos should always be offloaded to remote)
+    """
+
+    item_timeout = 86400 * 7  # One week
+
+    def get_remote_url(self):
+        self.post_attachment = get_object_or_404(
+            PostAttachment, pk=self.kwargs["attachment_id"]
+        )
+        if not self.post_attachment.is_image():
+            raise Http404()
+        return self.post_attachment.remote_url