Validate URLs before adding

feeds/views.py

@@ -6,18 +6,24 @@ FeedsView - /feeds
 
 from __future__ import annotations
 
+import logging
 import typing
+from urllib import parse
 
 from django.contrib import messages
+from django.core.exceptions import ValidationError
 from django.db import connection
-from django.shortcuts import redirect
+from django.shortcuts import redirect, render
 from django.views.generic.base import TemplateView
 from django.views.generic.list import ListView
 
-from feeds.models import Feed
+from feeds.models import Blocklist, Feed
+from feeds.validator import is_ip, is_local, validate_scheme
 
 if typing.TYPE_CHECKING:
-    from django.http import HttpRequest, HttpResponseRedirect
+    from django.http import HttpRequest, HttpResponse
+
+logger: logging.Logger = logging.getLogger(__name__)
 
 
 def get_database_size() -> int:
@@ -52,6 +58,9 @@ class IndexView(TemplateView):
         context: dict = super().get_context_data(**kwargs)
         context["feed_count"] = Feed.objects.count()
         context["database_size"] = get_database_size()
+
+        logger.info(f"Found {context['feed_count']} feeds in the database")  # noqa: G004
+        logger.info(f"Database size is {context['database_size']} MB")  # noqa: G004
         return context
 
 
@@ -72,33 +81,90 @@ class FeedsView(ListView):
         return context
 
 
-def add_feeds(request: HttpRequest) -> HttpResponseRedirect:
+def add_feeds(request: HttpRequest) -> HttpResponse:
     """Add feeds to the database.
 
     Args:
         request: The request object.
 
     Returns:
-        A redirect to the index page.
+        A redirect to the index page if there are errors, otherwise a redirect to the feeds page.
     """
     if request.method == "POST":
-        urls = request.POST.get("urls")
+        urls: str | None = request.POST.get("urls")
         if not urls:
             messages.error(request, "No URLs provided")
-            return redirect("feeds:index", permanent=False)
+            return render(request, "index.html")
 
         if urls == "Test":
-            messages.error(request, "Hello, world!")
-            return redirect("feeds:index", permanent=False)
+            messages.error(request, "Test test hello")
+            return render(request, "index.html")
 
         for url in urls.splitlines():
-            print(f"Adding {url} to the database...")  # noqa: T201
+            check_feeds(feed_urls=[url], request=request)
 
-        return redirect("feeds:feeds", permanent=False)
+        return render(request, "index.html")
 
     msg: str = f"You must use a POST request. You used a {request.method} request. You can find out how to use this endpoint here: <a href=''>http://127.0.0.1:8000/</a>. If you think this is a mistake, please contact the administrator."  # noqa: E501
     messages.error(request, msg)
-    return redirect("feeds:index", permanent=False)
+    return render(request, "index.html")
+
+
+def check_feeds(feed_urls: list[str], request: HttpRequest) -> HttpResponse:
+    """Check feeds before adding them to the database.
+
+    Args:
+        feed_urls: The feed URLs to check.
+        request: The request object.
+
+    Returns:
+        A redirect to the index page if there are errors, otherwise a redirect to the feeds page.
+    """
+    for url in feed_urls:
+        url_html: str = f"<a href='{url}'>{url}</a>"
+        if Feed.objects.filter(url=url).exists():
+            msg: str = f"{url_html} is already in the database."
+            messages.error(request, msg)
+            continue
+
+        # Only allow HTTP and HTTPS URLs
+        if not validate_scheme(feed_url=url):
+            msg = f"{url_html} is not a HTTP or HTTPS URL."
+            messages.error(request, msg)
+            continue
+
+        # Don't allow IP addresses
+        if is_ip(feed_url=url):
+            msg = f"{url_html} is an IP address. IP addresses are not allowed."
+            messages.error(request, msg)
+            continue
+
+        # Check if in blocklist
+        domain: str = parse.urlparse(url).netloc
+        if Blocklist.objects.filter(url=domain).exists():
+            msg = f"{url_html} is in the blocklist."
+            messages.error(request, msg)
+            continue
+
+        # Check if local URL
+        if is_local(feed_url=url):
+            msg = f"{url_html} is a local URL."
+            messages.error(request, msg)
+            continue
+
+        # Create feed
+        try:
+            Feed.objects.create(url=url)
+            msg = f"{url_html} was added to the database."
+            messages.success(request, msg)
+        except ValidationError:
+            msg = f"{url_html} is not a valid URL."
+            messages.error(request, msg)
+
+    # Return to feeds page if no errors
+    # TODO(TheLovinator): Return to search page with our new feeds  # noqa: TD003
+    logger.info(f"Added {len(feed_urls)} feeds to the database")  # noqa: G004
+    return redirect("feeds:feeds")
 
 
 class APIView(TemplateView):