Refactor HTML rendering into one place

Also suppress using external <a> tags for now, until we can separate
them from hashtags properly.

.pre-commit-config.yaml

@@ -46,6 +46,7 @@ repos:
     rev: v0.991
     hooks:
       - id: mypy
+        exclude: "^tests/"
         additional_dependencies:
           [
             types-pyopenssl,

activities/models/emoji.py

@@ -1,10 +1,11 @@
 import re
 from functools import partial
-from typing import ClassVar, cast
+from typing import ClassVar
 
 import httpx
 import urlman
 from asgiref.sync import sync_to_async
+from cachetools import TTLCache, cached
 from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.db import models
@@ -50,17 +51,18 @@ class EmojiStates(StateGraph):
 
 class EmojiQuerySet(models.QuerySet):
     def usable(self, domain: Domain | None = None):
-        if domain is None or domain.local:
-            visible_q = models.Q(local=True)
-        else:
-            visible_q = models.Q(public=True)
-            if Config.system.emoji_unreviewed_are_public:
-                visible_q |= models.Q(public__isnull=True)
-
+        """
+        Returns all usable emoji, optionally filtering by domain too.
+        """
+        visible_q = models.Q(local=True) | models.Q(public=True)
+        if Config.system.emoji_unreviewed_are_public:
+            visible_q |= models.Q(public__isnull=True)
         qs = self.filter(visible_q)
+
         if domain:
             if not domain.local:
                 qs = qs.filter(domain=domain)
+
         return qs
 
 
@@ -136,6 +138,13 @@ class Emoji(StatorModel):
     def load_locals(cls) -> dict[str, "Emoji"]:
         return {x.shortcode: x for x in Emoji.objects.usable().filter(local=True)}
 
+    @classmethod
+    @cached(cache=TTLCache(maxsize=1000, ttl=60))
+    def for_domain(cls, domain: Domain | None) -> list["Emoji"]:
+        if not domain:
+            return list(cls.locals.values())
+        return list(cls.objects.usable(domain))
+
     @property
     def fullcode(self):
         return f":{self.shortcode}:"
@@ -164,41 +173,6 @@ class Emoji(StatorModel):
             )
         return self.fullcode
 
-    @classmethod
-    def imageify_emojis(
-        cls,
-        content: str,
-        *,
-        emojis: list["Emoji"] | EmojiQuerySet | None = None,
-        include_local: bool = True,
-    ):
-        """
-        Find :emoji: in content and convert to <img>. If include_local is True,
-        the local emoji will be used as a fallback for any shortcodes not defined
-        by emojis.
-        """
-        emoji_set = (
-            cast(list[Emoji], list(cls.locals.values())) if include_local else []
-        )
-
-        if emojis:
-            if isinstance(emojis, (EmojiQuerySet, list)):
-                emoji_set.extend(list(emojis))
-            else:
-                raise TypeError("Unsupported type for emojis")
-
-        possible_matches = {
-            emoji.shortcode: emoji.as_html() for emoji in emoji_set if emoji.is_usable
-        }
-
-        def replacer(match):
-            fullcode = match.group(1).lower()
-            if fullcode in possible_matches:
-                return possible_matches[fullcode]
-            return match.group()
-
-        return mark_safe(Emoji.emoji_regex.sub(replacer, content))
-
     @classmethod
     def emojis_from_content(cls, content: str, domain: Domain | None) -> list[str]:
         """

activities/models/hashtag.py

@@ -5,7 +5,6 @@ import urlman
 from asgiref.sync import sync_to_async
 from django.db import models
 from django.utils import timezone
-from django.utils.safestring import mark_safe
 
 from core.html import strip_html
 from core.models import Config
@@ -176,19 +175,6 @@ class Hashtag(StatorModel):
         hashtags = sorted({tag.lower() for tag in hashtag_hits})
         return list(hashtags)
 
-    @classmethod
-    def linkify_hashtags(cls, content, domain=None) -> str:
-        def replacer(match):
-            hashtag = match.group(1)
-            if domain:
-                return f'<a class="hashtag" href="https://{domain.uri_domain}/tags/{hashtag.lower()}/">#{hashtag}</a>'
-            else:
-                return (
-                    f'<a class="hashtag" href="/tags/{hashtag.lower()}/">#{hashtag}</a>'
-                )
-
-        return mark_safe(Hashtag.hashtag_regex.sub(replacer, content))
-
     def to_mastodon_json(self):
         return {
             "name": self.hashtag,

activities/models/post.py

@@ -20,8 +20,7 @@ from activities.models.post_types import (
     PostTypeDataDecoder,
     PostTypeDataEncoder,
 )
-from activities.templatetags.emoji_tags import imageify_emojis
-from core.html import sanitize_post, strip_html
+from core.html import ContentRenderer, strip_html
 from core.ld import canonicalise, format_ld_date, get_list, parse_ld_date
 from stator.exceptions import TryAgainLater
 from stator.models import State, StateField, StateGraph, StatorModel
@@ -383,13 +382,7 @@ class Post(StatorModel):
         return mark_safe(self.mention_regex.sub(replacer, content))
 
     def _safe_content_note(self, *, local: bool = True):
-        content = Hashtag.linkify_hashtags(
-            self.linkify_mentions(sanitize_post(self.content), local=local),
-            domain=None if local else self.author.domain,
-        )
-        if local:
-            content = imageify_emojis(content, self.author.domain)
-        return content
+        return ContentRenderer(local=local).render_post(self.content, self)
 
     # def _safe_content_question(self, *, local: bool = True):
     #     context = {
@@ -432,12 +425,6 @@ class Post(StatorModel):
         """
         return self.safe_content(local=False)
 
-    def safe_content_plain(self):
-        """
-        Returns the content formatted as plain text
-        """
-        return self.linkify_mentions(sanitize_post(self.content))
-
     ### Async helpers ###
 
     async def afetch_full(self) -> "Post":
@@ -914,7 +901,7 @@ class Post(StatorModel):
             "poll": None,
             "card": None,
             "language": None,
-            "text": self.safe_content_plain(),
+            "text": self.safe_content_remote(),
             "edited_at": format_ld_date(self.edited) if self.edited else None,
         }
         if interactions:

activities/templatetags/activity_tags.py

@@ -3,8 +3,6 @@ import datetime
 from django import template
 from django.utils import timezone
 
-from activities.models import Hashtag
-
 register = template.Library()
 
 
@@ -33,14 +31,3 @@ def timedeltashort(value: datetime.datetime):
         years = max(days // 365.25, 1)
         text = f"{years:0n}y"
     return text
-
-
-@register.filter
-def linkify_hashtags(value: str):
-    """
-    Convert hashtags in content in to /tags/<hashtag>/ links.
-    """
-    if not value:
-        return ""
-
-    return Hashtag.linkify_hashtags(value)

activities/templatetags/emoji_tags.py

@@ -1,27 +0,0 @@
-from cachetools import TTLCache, cached
-from django import template
-
-from activities.models import Emoji
-from users.models import Domain
-
-register = template.Library()
-
-
-@cached(cache=TTLCache(maxsize=1000, ttl=60))
-def emoji_from_domain(domain: Domain | None) -> list[Emoji]:
-    if not domain:
-        return list(Emoji.locals.values())
-    return list(Emoji.objects.usable(domain))
-
-
-@register.filter
-def imageify_emojis(value: str, arg: Domain | None = None):
-    """
-    Convert hashtags in content in to /tags/<hashtag>/ links.
-    """
-    if not value:
-        return ""
-
-    emojis = emoji_from_domain(arg)
-
-    return Emoji.imageify_emojis(value, emojis=emojis)

activities/views/posts.py

@@ -40,6 +40,11 @@ class Individual(TemplateView):
         ancestors, descendants = PostService(self.post_obj).context(
             self.request.identity
         )
+        print(
+            self.post_obj.to_mastodon_json(),
+            self.post_obj.emojis.all(),
+            self.post_obj.emojis.usable(),
+        )
         return {
             "identity": self.identity,
             "post": self.post_obj,

api/views/emoji.py

@@ -5,4 +5,4 @@ from api.views.base import api_router
 
 @api_router.get("/v1/custom_emojis", response=list[CustomEmoji])
 def emojis(request):
-    return [e.to_mastodon_json() for e in Emoji.objects.usable()]
+    return [e.to_mastodon_json() for e in Emoji.objects.usable().filter(local=True)]

core/html.py

@@ -15,12 +15,12 @@ def allow_a(tag: str, name: str, value: str):
     return False
 
 
-def sanitize_post(post_html: str) -> str:
+def sanitize_html(post_html: str) -> str:
     """
     Only allows a, br, p and span tags, and class attributes.
     """
     cleaner = bleach.Cleaner(
-        tags=["br", "p", "a"],
+        tags=["br", "p"],
         attributes={  # type:ignore
             "a": allow_a,
             "p": ["class"],
@@ -50,3 +50,117 @@ def html_to_plaintext(post_html: str) -> str:
     # Remove all other HTML and return
     cleaner = bleach.Cleaner(tags=[], strip=True, filters=[])
     return cleaner.clean(post_html).strip()
+
+
+class ContentRenderer:
+    """
+    Renders HTML for posts, identity fields, and more.
+
+    The `local` parameter affects whether links are absolute (False) or relative (True)
+    """
+
+    def __init__(self, local: bool):
+        self.local = local
+
+    def render_post(self, html: str, post) -> str:
+        """
+        Given post HTML, normalises it and renders it for presentation.
+        """
+        if not html:
+            return ""
+        html = sanitize_html(html)
+        html = self.linkify_mentions(html, post=post)
+        html = self.linkify_hashtags(html, identity=post.author)
+        if self.local:
+            html = self.imageify_emojis(html, identity=post.author)
+        return mark_safe(html)
+
+    def render_identity(self, html: str, identity, strip: bool = False) -> str:
+        """
+        Given identity field HTML, normalises it and renders it for presentation.
+        """
+        if not html:
+            return ""
+        if strip:
+            html = strip_html(html)
+        else:
+            html = sanitize_html(html)
+        html = self.linkify_hashtags(html, identity=identity)
+        if self.local:
+            html = self.imageify_emojis(html, identity=identity)
+        return mark_safe(html)
+
+    def linkify_mentions(self, html: str, post) -> str:
+        """
+        Links mentions _in the context of the post_ - as in, using the mentions
+        property as the only source (as we might be doing this without other
+        DB access allowed)
+        """
+        from activities.models import Post
+
+        possible_matches = {}
+        for mention in post.mentions.all():
+            if self.local:
+                url = str(mention.urls.view)
+            else:
+                url = mention.absolute_profile_uri()
+            possible_matches[mention.username] = url
+            possible_matches[f"{mention.username}@{mention.domain_id}"] = url
+
+        collapse_name: dict[str, str] = {}
+
+        def replacer(match):
+            precursor = match.group(1)
+            handle = match.group(2).lower()
+            if "@" in handle:
+                short_handle = handle.split("@", 1)[0]
+            else:
+                short_handle = handle
+            if handle in possible_matches:
+                if short_handle not in collapse_name:
+                    collapse_name[short_handle] = handle
+                elif collapse_name.get(short_handle) != handle:
+                    short_handle = handle
+                return f'{precursor}<a href="{possible_matches[handle]}">@{short_handle}</a>'
+            else:
+                return match.group()
+
+        return Post.mention_regex.sub(replacer, html)
+
+    def linkify_hashtags(self, html, identity) -> str:
+        from activities.models import Hashtag
+
+        def replacer(match):
+            hashtag = match.group(1)
+            if self.local:
+                return (
+                    f'<a class="hashtag" href="/tags/{hashtag.lower()}/">#{hashtag}</a>'
+                )
+            else:
+                return f'<a class="hashtag" href="https://{identity.domain.uri_domain}/tags/{hashtag.lower()}/">#{hashtag}</a>'
+
+        return Hashtag.hashtag_regex.sub(replacer, html)
+
+    def imageify_emojis(self, html: str, identity, include_local: bool = True):
+        """
+        Find :emoji: in content and convert to <img>. If include_local is True,
+        the local emoji will be used as a fallback for any shortcodes not defined
+        by emojis.
+        """
+        from activities.models import Emoji
+
+        emoji_set = Emoji.for_domain(identity.domain)
+        if include_local:
+            emoji_set.extend(Emoji.for_domain(None))
+
+        possible_matches = {
+            emoji.shortcode: emoji.as_html() for emoji in emoji_set if emoji.is_usable
+        }
+
+        def replacer(match):
+            fullcode = match.group(1).lower()
+            if fullcode in possible_matches:
+                return possible_matches[fullcode]
+            return match.group()
+
+        return Emoji.emoji_regex.sub(replacer, html)

setup.cfg

@@ -15,6 +15,7 @@ filterwarnings =
 
 [mypy]
 warn_unused_ignores = True
+exclude = tests
 
 [mypy-django.*]
 ignore_missing_imports = True

templates/identity/view.html

@@ -1,5 +1,4 @@
 {% extends "base.html" %}
-{% load emoji_tags %}
 
 {% block title %}{{ identity }}{% endblock %}
 

tests/activities/models/test_hashtag.py

@@ -1,4 +1,5 @@
 from activities.models import Hashtag
+from core.html import ContentRenderer
 
 
 def test_hashtag_from_content():
@@ -19,7 +20,7 @@ def test_hashtag_from_content():
 
 
 def test_linkify_hashtag():
-    linkify = Hashtag.linkify_hashtags
+    linkify = lambda html: ContentRenderer(local=True).linkify_hashtags(html, None)
 
     assert linkify("# hashtag") == "# hashtag"
     assert (

tests/activities/models/test_post.py

@@ -9,6 +9,16 @@ def test_fetch_post(httpx_mock: HTTPXMock, config_system):
     """
     Tests that a post we don't have locally can be fetched by by_object_uri
     """
+    httpx_mock.add_response(
+        url="https://example.com/test-actor",
+        json={
+            "@context": [
+                "https://www.w3.org/ns/activitystreams",
+            ],
+            "id": "https://example.com/test-actor",
+            "type": "Person",
+        },
+    )
     httpx_mock.add_response(
         url="https://example.com/test-post",
         json={

tests/activities/models/test_post_types.py

@@ -6,19 +6,19 @@ from core.ld import canonicalise
 
 
 @pytest.mark.django_db
-def test_question_post(config_system, identity, remote_identity):
+def test_question_post(config_system, identity, remote_identity, httpx_mock):
     data = {
         "cc": [],
-        "id": "https://fosstodon.org/users/manfre/statuses/109519951621804608/activity",
+        "id": "https://remote.test/test-actor/statuses/109519951621804608/activity",
         "to": identity.absolute_profile_uri(),
         "type": "Create",
-        "actor": "https://fosstodon.org/users/manfre",
+        "actor": "https://remote.test/test-actor/",
         "object": {
             "cc": [],
-            "id": "https://fosstodon.org/users/manfre/statuses/109519951621804608",
+            "id": "https://remote.test/test-actor/statuses/109519951621804608",
             "to": identity.absolute_profile_uri(),
             "tag": [],
-            "url": "https://fosstodon.org/@manfre/109519951621804608",
+            "url": "https://remote.test/test-actor/109519951621804608",
             "type": "Question",
             "oneOf": [
                 {
@@ -35,13 +35,13 @@ def test_question_post(config_system, identity, remote_identity):
             "content": '<p>This is a poll :python: </p><p><span class="h-card"><a href="https://ehakat.manfre.net/@mike/" class="u-url mention">@<span>mike</span></a></span></p>',
             "endTime": "2022-12-18T22:03:59Z",
             "replies": {
-                "id": "https://fosstodon.org/users/manfre/statuses/109519951621804608/replies",
+                "id": "https://remote.test/test-actor/statuses/109519951621804608/replies",
                 "type": "Collection",
                 "first": {
-                    "next": "https://fosstodon.org/users/manfre/statuses/109519951621804608/replies?only_other_accounts=true&page=true",
+                    "next": "https://remote.test/test-actor/109519951621804608/replies?only_other_accounts=true&page=true",
                     "type": "CollectionPage",
                     "items": [],
-                    "partOf": "https://fosstodon.org/users/manfre/statuses/109519951621804608/replies",
+                    "partOf": "https://remote.test/test-actor/109519951621804608/replies",
                 },
             },
             "published": "2022-12-15T22:03:59Z",
@@ -50,15 +50,9 @@ def test_question_post(config_system, identity, remote_identity):
                 "en": '<p>This is a poll :python: </p><p><span class="h-card"><a href="https://ehakat.manfre.net/@mike/" class="u-url mention">@<span>mike</span></a></span></p>'
             },
             "as:sensitive": False,
-            "attributedTo": "https://fosstodon.org/users/manfre",
-            "http://ostatus.org#atomUri": "https://fosstodon.org/users/manfre/statuses/109519951621804608",
-            "http://ostatus.org#conversation": "tag:fosstodon.org,2022-12-15:objectId=69494364:objectType=Conversation",
-            "http://joinmastodon.org/ns#votersCount": 0,
+            "attributedTo": "https://remote.test/test-actor/",
+            "toot:votersCount": 0,
         },
-        "@context": [
-            "https://www.w3.org/ns/activitystreams",
-            "https://w3id.org/security/v1",
-        ],
         "published": "2022-12-15T22:03:59Z",
     }
 

tests/activities/services/test_post.py

@@ -6,7 +6,7 @@ from users.models import Identity
 
 
 @pytest.mark.django_db
-def test_post_context(identity: Identity):
+def test_post_context(identity: Identity, config_system):
     """
     Tests that post context fetching works correctly
     """

tests/activities/templatetags/test_activity_tags.py

@@ -2,7 +2,7 @@ from datetime import timedelta
 
 from django.utils import timezone
 
-from activities.templatetags.activity_tags import linkify_hashtags, timedeltashort
+from activities.templatetags.activity_tags import timedeltashort
 
 
 def test_timedeltashort():
@@ -22,17 +22,3 @@ def test_timedeltashort():
     assert timedeltashort(value - timedelta(days=364)) == "364d"
     assert timedeltashort(value - timedelta(days=365)) == "1y"
     assert timedeltashort(value - timedelta(days=366)) == "1y"
-
-
-def test_linkify_hashtags():
-    """
-    Tests that linkify_hashtags works correctly
-    """
-
-    assert linkify_hashtags(None) == ""
-    assert linkify_hashtags("") == ""
-
-    assert (
-        linkify_hashtags("#Takahe")
-        == '<a class="hashtag" href="/tags/takahe/">#Takahe</a>'
-    )

tests/core/test_html.py

@@ -1,4 +1,4 @@
-from core.html import html_to_plaintext, sanitize_post
+from core.html import html_to_plaintext, sanitize_html
 
 
 def test_html_to_plaintext():
@@ -17,5 +17,5 @@ def test_html_to_plaintext():
 
 def test_sanitize_post():
 
-    assert sanitize_post("<p>Hello!</p>") == "<p>Hello!</p>"
-    assert sanitize_post("<p>It&#39;s great</p>") == "<p>It&#39;s great</p>"
+    assert sanitize_html("<p>Hello!</p>") == "<p>Hello!</p>"
+    assert sanitize_html("<p>It&#39;s great</p>") == "<p>It&#39;s great</p>"

users/models/identity.py

@@ -11,7 +11,7 @@ from django.utils import timezone
 from django.utils.functional import lazy
 
 from core.exceptions import ActorMismatchError
-from core.html import sanitize_post, strip_html
+from core.html import ContentRenderer, strip_html
 from core.ld import (
     canonicalise,
     format_ld_date,
@@ -192,20 +192,18 @@ class Identity(StatorModel):
 
     @property
     def safe_summary(self):
-        from activities.templatetags.emoji_tags import imageify_emojis
-
-        return imageify_emojis(sanitize_post(self.summary), self.domain)
+        return ContentRenderer(local=True).render_identity(self.summary, self)
 
     @property
     def safe_metadata(self):
-        from activities.templatetags.emoji_tags import imageify_emojis
+        renderer = ContentRenderer(local=True)
 
         if not self.metadata:
             return []
         return [
             {
-                "name": imageify_emojis(strip_html(data["name"]), self.domain),
-                "value": imageify_emojis(strip_html(data["value"]), self.domain),
+                "name": renderer.render_identity(data["name"], self, strip=True),
+                "value": renderer.render_identity(data["value"], self, strip=True),
             }
             for data in self.metadata
         ]
@@ -279,9 +277,9 @@ class Identity(StatorModel):
         """
         Return the name_or_handle with any HTML substitutions made
         """
-        from activities.templatetags.emoji_tags import imageify_emojis
-
-        return imageify_emojis(self.name_or_handle, self.domain)
+        return ContentRenderer(local=True).render_identity(
+            self.name_or_handle, self, strip=True
+        )
 
     @property
     def handle(self):