Remove specialized coronavirus views

Coronavirus topics have slowed down greatly now, with generally only
about 3 per day, and are almost all restricted to ~health.coronavirus,
so users can easily find (or avoid) them by just using that group.

tildes/tildes/request_methods.py

@@ -121,7 +121,7 @@ def current_listing_base_url(
         "bookmarks": ("per_page", "type"),
         "group": ("order", "period", "per_page", "tag", "unfiltered"),
         "group_search": ("order", "period", "per_page", "q"),
-        "home": ("order", "period", "per_page", "tag", "unfiltered", "view"),
+        "home": ("order", "period", "per_page", "tag", "unfiltered"),
         "ignored_topics": ("per_page",),
         "search": ("order", "period", "per_page", "q"),
         "user": ("order", "per_page", "type"),

tildes/tildes/templates/home.jinja2

@@ -13,27 +13,7 @@
   <meta property="og:description" content="Tildes is a non-profit community site with no advertising or investors. It respects its users and their privacy, and prioritizes high-quality content and discussions.">
 {% endblock %}
 
-{% block header_context_link %}
-  {% if not view %}
-    <div class="toast toast-minor" id="coronavirus-views">Specialized views: <a href="/?view=coronavirus-filtered">No coronavirus topics</a> / <a href="/?view=coronavirus-only">Only coronavirus topics</a></div>
-  {% endif %}
-{% endblock %}
-
-{% block filter_info %}
-  {% if view %}
-    <div class="topic-listing-filter">
-      {% if view == "coronavirus-only" %}
-        Showing only topics related to coronavirus.
-      {% elif view == "coronavirus-filtered" %}
-        Showing only topics <em>not</em> related to coronavirus.
-      {% endif %}
-
-      <a href="/">Back to normal view</a>
-    </div>
-  {% endif %}
-
-  {{ super() }}
-{% endblock %}
+{% block header_context_link %}{% endblock %}
 
 {% block content %}
   {% if request.user %}

tildes/tildes/templates/topic_listing.jinja2

@@ -49,10 +49,6 @@
       <input type="hidden" name="q" value="{{ search }}">
     {% endif %}
 
-    {% if view is defined %}
-      <input type="hidden" name="view" value="{{ view }}">
-    {% endif %}
-
     <div class="form-group">
       <label for="period">from</label>
       <select id="period" name="period" class="form-select" data-js-time-period-select>

tildes/tildes/views/topic.py

@@ -14,7 +14,7 @@ from pyramid.renderers import render_to_response
 from pyramid.request import Request
 from pyramid.response import Response
 from pyramid.view import view_config
-from sqlalchemy import cast, or_
+from sqlalchemy import cast
 from sqlalchemy.sql.expression import any_, desc, text
 from sqlalchemy_utils import Ltree
 from webargs.pyramidparser import use_kwargs
@@ -140,7 +140,6 @@ def post_group_topics(
 @view_config(route_name="home", renderer="home.jinja2")
 @view_config(route_name="group", renderer="topic_listing.jinja2")
 @use_kwargs(TopicListingSchema())
-@use_kwargs({"view": String(missing=None)})
 def get_group_topics(  # noqa
     request: Request,
     after: Optional[str],
@@ -150,7 +149,6 @@ def get_group_topics(  # noqa
     rank_start: Optional[int],
     tag: Optional[Ltree],
     unfiltered: bool,
-    view: Optional[str],
     **kwargs: Any
 ) -> dict:
     """Get a listing of topics in the group."""
@@ -159,31 +157,11 @@ def get_group_topics(  # noqa
 
     is_home_page = request.matched_route.name == "home"
 
-    # only allow the special coronavirus views on the home page
-    if not is_home_page:
-        view = None
-
-    if view:
-        coronavirus_group = (
-            request.query(Group)
-            .filter(Group.path == Ltree("health.coronavirus"))
-            .one_or_none()
-        )
-    else:
-        coronavirus_group = None
-
     if is_home_page:
         # on the home page, include topics from the user's subscribed groups
         # (or all groups, if logged-out)
         if request.user:
             groups = [sub.group for sub in request.user.subscriptions]
-
-            if (
-                view == "coronavirus-only"
-                and coronavirus_group
-                and coronavirus_group not in groups
-            ):
-                groups.append(coronavirus_group)
         else:
             groups = [
                 group for group in request.query(Group).all() if group.path != "test"
@@ -219,20 +197,6 @@ def get_group_topics(  # noqa
         .apply_sort_option(order)
     )
 
-    if view and coronavirus_group:
-        if view == "coronavirus-only":
-            query = query.filter(  # noqa
-                or_(
-                    Topic.group_id == coronavirus_group.group_id,
-                    Topic.tags.contains(["coronaviruses.covid19"]),  # type: ignore
-                )
-            )
-        elif view == "coronavirus-filtered":
-            query = query.filter(
-                Topic.group_id != coronavirus_group.group_id,
-                ~Topic.tags.contains(["coronaviruses.covid19"]),  # type: ignore
-            )
-
     # restrict the time period, if not set to "all time"
     if period:
         query = query.inside_time_period(period)
@@ -331,7 +295,6 @@ def get_group_topics(  # noqa
         "most_recent_scheduled_topics": most_recent_scheduled_topics,
         "financial_data": financial_data,
         "current_time": utc_now(),
-        "view": view,
     }