Post URIs and host-meta

12 files changed, 234 insertions, 162 deletions

diff --git a/activities/migrations/0003_alter_post_object_uri.py b/activities/migrations/0003_alter_post_object_uri.py
new file mode 100644
index 0000000..4f98bc9
--- /dev/null
+++ b/activities/migrations/0003_alter_post_object_uri.py
@@ -0,0 +1,18 @@
+# Generated by Django 4.1.3 on 2022-11-13 03:09
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("activities", "0002_fan_out"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="post",
+            name="object_uri",
+            field=models.CharField(blank=True, max_length=500, null=True, unique=True),
+        ),
+    ]
diff --git a/activities/models/fan_out.py b/activities/models/fan_out.py
index 96e8df7..958fbe2 100644
--- a/activities/models/fan_out.py
+++ b/activities/models/fan_out.py
@@ -32,7 +32,7 @@ class FanOutStates(StateGraph):
             await HttpSignature.signed_request(
                 uri=fan_out.identity.inbox_uri,
                 body=canonicalise(post.to_create_ap()),
-                private_key=post.author.public_key,
+                private_key=post.author.private_key,
                 key_id=post.author.public_key_id,
             )
         return cls.sent
diff --git a/activities/models/post.py b/activities/models/post.py
index 4c40033..ec5e629 100644
--- a/activities/models/post.py
+++ b/activities/models/post.py
@@ -7,7 +7,7 @@ from django.utils import timezone
 from activities.models.fan_out import FanOut
 from activities.models.timeline_event import TimelineEvent
 from core.html import sanitize_post
-from core.ld import format_date
+from core.ld import format_ld_date, parse_ld_date
 from stator.models import State, StateField, StateGraph, StatorModel
 from users.models.follow import Follow
 from users.models.identity import Identity
@@ -53,7 +53,7 @@ class Post(StatorModel):
     local = models.BooleanField()
 
     # The canonical object ID
-    object_uri = models.CharField(max_length=500, blank=True, null=True)
+    object_uri = models.CharField(max_length=500, blank=True, null=True, unique=True)
 
     # Who should be able to see this Post
     visibility = models.IntegerField(
@@ -145,18 +145,22 @@ class Post(StatorModel):
         """
         # Send a copy to all people who follow this user
         post = await self.afetch_full()
-        async for follow in post.author.inbound_follows.all():
+        async for follow in post.author.inbound_follows.select_related(
+            "source", "target"
+        ):
+            if follow.source.local or follow.target.local:
+                await FanOut.objects.acreate(
+                    identity_id=follow.source_id,
+                    type=FanOut.Types.post,
+                    subject_post=post,
+                )
+        # And one for themselves if they're local
+        if post.author.local:
             await FanOut.objects.acreate(
-                identity_id=follow.source_id,
+                identity_id=post.author_id,
                 type=FanOut.Types.post,
                 subject_post=post,
             )
-        # And one for themselves
-        await FanOut.objects.acreate(
-            identity_id=post.author_id,
-            type=FanOut.Types.post,
-            subject_post=post,
-        )
 
     def to_ap(self) -> Dict:
         """
@@ -165,7 +169,7 @@ class Post(StatorModel):
         value = {
             "type": "Note",
             "id": self.object_uri,
-            "published": format_date(self.created),
+            "published": format_ld_date(self.created),
             "attributedTo": self.author.actor_uri,
             "content": self.safe_content,
             "to": "as:Public",
@@ -190,7 +194,7 @@ class Post(StatorModel):
     ### ActivityPub (inbound) ###
 
     @classmethod
-    def by_ap(cls, data, create=False) -> "Post":
+    def by_ap(cls, data, create=False, update=False) -> "Post":
         """
         Retrieves a Post instance by its ActivityPub JSON object.
 
@@ -198,25 +202,33 @@ class Post(StatorModel):
         Raises KeyError if it's not found and create is False.
         """
         # Do we have one with the right ID?
+        created = False
         try:
-            return cls.objects.get(object_uri=data["id"])
+            post = cls.objects.get(object_uri=data["id"])
         except cls.DoesNotExist:
             if create:
                 # Resolve the author
                 author = Identity.by_actor_uri(data["attributedTo"], create=create)
-                return cls.objects.create(
+                post = cls.objects.create(
+                    object_uri=data["id"],
                     author=author,
                     content=sanitize_post(data["content"]),
-                    summary=data.get("summary", None),
-                    sensitive=data.get("as:sensitive", False),
-                    url=data.get("url", None),
                     local=False,
-                    # TODO: to
-                    # TODO: mentions
-                    # TODO: visibility
                 )
+                created = True
             else:
                 raise KeyError(f"No post with ID {data['id']}", data)
+        if update or created:
+            post.content = sanitize_post(data["content"])
+            post.summary = data.get("summary", None)
+            post.sensitive = data.get("as:sensitive", False)
+            post.url = data.get("url", None)
+            post.authored = parse_ld_date(data.get("published", None))
+            # TODO: to
+            # TODO: mentions
+            # TODO: visibility
+            post.save()
+        return post
 
     @classmethod
     def handle_create_ap(cls, data):
@@ -227,7 +239,7 @@ class Post(StatorModel):
         if data["actor"] != data["object"]["attributedTo"]:
             raise ValueError("Create actor does not match its Post object", data)
         # Create it
-        post = cls.by_ap(data["object"], create=True)
+        post = cls.by_ap(data["object"], create=True, update=True)
         # Make timeline events as appropriate
         for follow in Follow.objects.filter(target=post.author, source__local=True):
             TimelineEvent.add_post(follow.source, post)
diff --git a/core/ld.py b/core/ld.py
index 7863480..346708c 100644
--- a/core/ld.py
+++ b/core/ld.py
@@ -1,6 +1,6 @@
 import datetime
 import urllib.parse as urllib_parse
-from typing import Dict, List, Union
+from typing import Dict, List, Optional, Union
 
 from pyld import jsonld
 from pyld.jsonld import JsonLdError
@@ -414,5 +414,13 @@ def canonicalise(json_data: Dict, include_security: bool = False) -> Dict:
     return jsonld.compact(jsonld.expand(json_data), context)
 
 
-def format_date(value: datetime.datetime) -> str:
+def format_ld_date(value: datetime.datetime) -> str:
     return value.strftime(DATETIME_FORMAT)
+
+
+def parse_ld_date(value: Optional[str]) -> Optional[datetime.datetime]:
+    if value is None:
+        return None
+    return datetime.datetime.strptime(value, DATETIME_FORMAT).replace(
+        tzinfo=datetime.timezone.utc
+    )
diff --git a/core/signatures.py b/core/signatures.py
index 74b5324..0959333 100644
--- a/core/signatures.py
+++ b/core/signatures.py
@@ -11,7 +11,7 @@ from django.utils.http import http_date, parse_http_date
 from OpenSSL import crypto
 from pyld import jsonld
 
-from core.ld import format_date
+from core.ld import format_ld_date
 
 
 class VerificationError(BaseException):
@@ -261,7 +261,7 @@ class LDSignature:
         options: Dict[str, str] = {
             "@context": "https://w3id.org/identity/v1",
             "creator": key_id,
-            "created": format_date(timezone.now()),
+            "created": format_ld_date(timezone.now()),
         }
         # Get the normalised hash of each document
         final_hash = cls.normalized_hash(options) + cls.normalized_hash(document)
diff --git a/takahe/urls.py b/takahe/urls.py
index 764c8e9..672f7ce 100644
--- a/takahe/urls.py
+++ b/takahe/urls.py
@@ -3,7 +3,7 @@ from django.urls import path
 
 from core import views as core
 from stator import views as stator
-from users.views import auth, identity
+from users.views import activitypub, auth, identity
 
 urlpatterns = [
     path("", core.homepage),
@@ -12,15 +12,16 @@ urlpatterns = [
     path("auth/logout/", auth.Logout.as_view()),
     # Identity views
     path("@<handle>/", identity.ViewIdentity.as_view()),
-    path("@<handle>/actor/", identity.Actor.as_view()),
-    path("@<handle>/actor/inbox/", identity.Inbox.as_view()),
+    path("@<handle>/actor/", activitypub.Actor.as_view()),
+    path("@<handle>/actor/inbox/", activitypub.Inbox.as_view()),
     path("@<handle>/action/", identity.ActionIdentity.as_view()),
     # Identity selection
     path("@<handle>/activate/", identity.ActivateIdentity.as_view()),
     path("identity/select/", identity.SelectIdentity.as_view()),
     path("identity/create/", identity.CreateIdentity.as_view()),
     # Well-known endpoints
-    path(".well-known/webfinger", identity.Webfinger.as_view()),
+    path(".well-known/webfinger", activitypub.Webfinger.as_view()),
+    path(".well-known/host-meta", activitypub.HostMeta.as_view()),
     # Task runner
     path(".stator/runner/", stator.RequestRunner.as_view()),
     # Django admin
diff --git a/templates/activities/_post.html b/templates/activities/_post.html
index 2ac57f3..eef09db 100644
--- a/templates/activities/_post.html
+++ b/templates/activities/_post.html
@@ -13,7 +13,13 @@
         </a>
     </h3>
     <time>
-        <a href="{{ post.urls.view }}">{{ post.created | timesince }} ago</a>
+        <a href="{{ post.urls.view }}">
+            {% if post.authored %}
+                {{ post.authored | timesince }} ago
+            {% else %}
+                {{ post.created | timesince }} ago
+            {% endif %}
+        </a>
     </time>
     <div class="content">
         {{ post.safe_content }}
diff --git a/users/admin.py b/users/admin.py
index 61a2bc8..e52e41c 100644
--- a/users/admin.py
+++ b/users/admin.py
@@ -38,7 +38,7 @@ class FollowAdmin(admin.ModelAdmin):
 
 @admin.register(InboxMessage)
 class InboxMessageAdmin(admin.ModelAdmin):
-    list_display = ["id", "state", "state_attempted", "message_type"]
+    list_display = ["id", "state", "state_attempted", "message_type", "message_actor"]
     actions = ["reset_state"]
 
     @admin.action(description="Reset State")
diff --git a/users/models/follow.py b/users/models/follow.py
index 238081e..0236d19 100644
--- a/users/models/follow.py
+++ b/users/models/follow.py
@@ -37,7 +37,7 @@ class FollowStates(StateGraph):
         await HttpSignature.signed_request(
             uri=follow.target.inbox_uri,
             body=canonicalise(follow.to_ap()),
-            private_key=follow.source.public_key,
+            private_key=follow.source.private_key,
             key_id=follow.source.public_key_id,
         )
         return cls.local_requested
@@ -57,7 +57,7 @@ class FollowStates(StateGraph):
         await HttpSignature.signed_request(
             uri=follow.source.inbox_uri,
             body=canonicalise(follow.to_accept_ap()),
-            private_key=follow.target.public_key,
+            private_key=follow.target.private_key,
             key_id=follow.target.public_key_id,
         )
         return cls.accepted
@@ -71,7 +71,7 @@ class FollowStates(StateGraph):
         await HttpSignature.signed_request(
             uri=follow.target.inbox_uri,
             body=canonicalise(follow.to_undo_ap()),
-            private_key=follow.source.public_key,
+            private_key=follow.source.private_key,
             key_id=follow.source.public_key_id,
         )
         return cls.undone_remotely
diff --git a/users/models/inbox_message.py b/users/models/inbox_message.py
index ea55b17..43424c9 100644
--- a/users/models/inbox_message.py
+++ b/users/models/inbox_message.py
@@ -66,3 +66,7 @@ class InboxMessage(StatorModel):
     @property
     def message_object_type(self):
         return self.message["object"]["type"].lower()
+
+    @property
+    def message_actor(self):
+        return self.message.get("actor")
diff --git a/users/views/activitypub.py b/users/views/activitypub.py
new file mode 100644
index 0000000..54f04bc
--- /dev/null
+++ b/users/views/activitypub.py
@@ -0,0 +1,148 @@
+import json
+
+from asgiref.sync import async_to_sync
+from django.http import Http404, HttpResponse, HttpResponseBadRequest, JsonResponse
+from django.utils.decorators import method_decorator
+from django.views.decorators.csrf import csrf_exempt
+from django.views.generic import View
+
+from core.ld import canonicalise
+from core.signatures import (
+    HttpSignature,
+    LDSignature,
+    VerificationError,
+    VerificationFormatError,
+)
+from users.models import Identity, InboxMessage
+from users.shortcuts import by_handle_or_404
+
+
+class HttpResponseUnauthorized(HttpResponse):
+    status_code = 401
+
+
+class HostMeta(View):
+    """
+    Returns a canned host-meta response
+    """
+
+    def get(self, request):
+        return HttpResponse(
+            """<?xml version="1.0" encoding="UTF-8"?>
+            <XRD xmlns="http://docs.oasis-open.org/ns/xri/xrd-1.0">
+            <Link rel="lrdd" template="https://%s/.well-known/webfinger?resource={uri}"/>
+            </XRD>"""
+            % request.META["HTTP_HOST"],
+            content_type="application/xml",
+        )
+
+
+class Webfinger(View):
+    """
+    Services webfinger requests
+    """
+
+    def get(self, request):
+        resource = request.GET.get("resource")
+        if not resource.startswith("acct:"):
+            raise Http404("Not an account resource")
+        handle = resource[5:].replace("testfedi", "feditest")
+        identity = by_handle_or_404(request, handle)
+        return JsonResponse(
+            {
+                "subject": f"acct:{identity.handle}",
+                "aliases": [
+                    identity.urls.view_short.full(),
+                ],
+                "links": [
+                    {
+                        "rel": "http://webfinger.net/rel/profile-page",
+                        "type": "text/html",
+                        "href": identity.urls.view_short.full(),
+                    },
+                    {
+                        "rel": "self",
+                        "type": "application/activity+json",
+                        "href": identity.actor_uri,
+                    },
+                ],
+            }
+        )
+
+
+class Actor(View):
+    """
+    Returns the AP Actor object
+    """
+
+    def get(self, request, handle):
+        identity = by_handle_or_404(self.request, handle)
+        response = {
+            "@context": [
+                "https://www.w3.org/ns/activitystreams",
+                "https://w3id.org/security/v1",
+            ],
+            "id": identity.actor_uri,
+            "type": "Person",
+            "inbox": identity.actor_uri + "inbox/",
+            "preferredUsername": identity.username,
+            "publicKey": {
+                "id": identity.public_key_id,
+                "owner": identity.actor_uri,
+                "publicKeyPem": identity.public_key,
+            },
+            "published": identity.created.strftime("%Y-%m-%dT%H:%M:%SZ"),
+            "url": identity.urls.view_short.full(),
+        }
+        if identity.name:
+            response["name"] = identity.name
+        if identity.summary:
+            response["summary"] = identity.summary
+        return JsonResponse(canonicalise(response, include_security=True))
+
+
+@method_decorator(csrf_exempt, name="dispatch")
+class Inbox(View):
+    """
+    AP Inbox endpoint
+    """
+
+    def post(self, request, handle):
+        # Load the LD
+        document = canonicalise(json.loads(request.body), include_security=True)
+        # Find the Identity by the actor on the incoming item
+        # This ensures that the signature used for the headers matches the actor
+        # described in the payload.
+        identity = Identity.by_actor_uri(document["actor"], create=True)
+        if not identity.public_key:
+            # See if we can fetch it right now
+            async_to_sync(identity.fetch_actor)()
+        if not identity.public_key:
+            print("Cannot get actor")
+            return HttpResponseBadRequest("Cannot retrieve actor")
+        # If there's a "signature" payload, verify against that
+        if "signature" in document:
+            try:
+                LDSignature.verify_signature(document, identity.public_key)
+            except VerificationFormatError as e:
+                print("Bad LD signature format:", e.args[0])
+                return HttpResponseBadRequest(e.args[0])
+            except VerificationError:
+                print("Bad LD signature")
+                return HttpResponseUnauthorized("Bad signature")
+        # Otherwise, verify against the header (assuming it's the same actor)
+        else:
+            try:
+                HttpSignature.verify_request(
+                    request,
+                    identity.public_key,
+                )
+            except VerificationFormatError as e:
+                print("Bad HTTP signature format:", e.args[0])
+                return HttpResponseBadRequest(e.args[0])
+            except VerificationError:
+                print("Bad HTTP signature")
+                return HttpResponseUnauthorized("Bad signature")
+        # Hand off the item to be processed by the queue
+        InboxMessage.objects.create(message=document)
+        return HttpResponse(status=202)
diff --git a/users/views/identity.py b/users/views/identity.py
index d4e1155..5d11d63 100644
--- a/users/views/identity.py
+++ b/users/views/identity.py
@@ -1,33 +1,19 @@
-import json
 import string
 
-from asgiref.sync import async_to_sync
 from django import forms
 from django.conf import settings
 from django.contrib.auth.decorators import login_required
-from django.http import Http404, HttpResponse, HttpResponseBadRequest, JsonResponse
+from django.http import Http404
 from django.shortcuts import redirect
 from django.utils.decorators import method_decorator
-from django.views.decorators.csrf import csrf_exempt
 from django.views.generic import FormView, TemplateView, View
 
 from core.forms import FormHelper
-from core.ld import canonicalise
-from core.signatures import (
-    HttpSignature,
-    LDSignature,
-    VerificationError,
-    VerificationFormatError,
-)
 from users.decorators import identity_required
-from users.models import Domain, Follow, Identity, IdentityStates, InboxMessage
+from users.models import Domain, Follow, Identity, IdentityStates
 from users.shortcuts import by_handle_or_404
 
 
-class HttpResponseUnauthorized(HttpResponse):
-    status_code = 401
-
-
 class ViewIdentity(TemplateView):
 
     template_name = "identity/view.html"
@@ -151,114 +137,3 @@ class CreateIdentity(FormView):
         new_identity.users.add(self.request.user)
         new_identity.generate_keypair()
         return redirect(new_identity.urls.view)
-
-
-class Actor(View):
-    """
-    Returns the AP Actor object
-    """
-
-    def get(self, request, handle):
-        identity = by_handle_or_404(self.request, handle)
-        response = {
-            "@context": [
-                "https://www.w3.org/ns/activitystreams",
-                "https://w3id.org/security/v1",
-            ],
-            "id": identity.actor_uri,
-            "type": "Person",
-            "inbox": identity.actor_uri + "inbox/",
-            "preferredUsername": identity.username,
-            "publicKey": {
-                "id": identity.public_key_id,
-                "owner": identity.actor_uri,
-                "publicKeyPem": identity.public_key,
-            },
-            "published": identity.created.strftime("%Y-%m-%dT%H:%M:%SZ"),
-            "url": identity.urls.view_short.full(),
-        }
-        if identity.name:
-            response["name"] = identity.name
-        if identity.summary:
-            response["summary"] = identity.summary
-        return JsonResponse(canonicalise(response, include_security=True))
-
-
-@method_decorator(csrf_exempt, name="dispatch")
-class Inbox(View):
-    """
-    AP Inbox endpoint
-    """
-
-    def post(self, request, handle):
-        # Load the LD
-        document = canonicalise(json.loads(request.body), include_security=True)
-        # Find the Identity by the actor on the incoming item
-        # This ensures that the signature used for the headers matches the actor
-        # described in the payload.
-        identity = Identity.by_actor_uri(document["actor"], create=True)
-        if not identity.public_key:
-            # See if we can fetch it right now
-            async_to_sync(identity.fetch_actor)()
-        if not identity.public_key:
-            print("Cannot get actor")
-            return HttpResponseBadRequest("Cannot retrieve actor")
-        # If there's a "signature" payload, verify against that
-        if "signature" in document:
-            try:
-                LDSignature.verify_signature(document, identity.public_key)
-            except VerificationFormatError as e:
-                print("Bad LD signature format:", e.args[0])
-                return HttpResponseBadRequest(e.args[0])
-            except VerificationError:
-                print("Bad LD signature")
-                return HttpResponseUnauthorized("Bad signature")
-        # Otherwise, verify against the header (assuming it's the same actor)
-        else:
-            try:
-                HttpSignature.verify_request(
-                    request,
-                    identity.public_key,
-                )
-            except VerificationFormatError as e:
-                print("Bad HTTP signature format:", e.args[0])
-                return HttpResponseBadRequest(e.args[0])
-            except VerificationError:
-                print("Bad HTTP signature")
-                return HttpResponseUnauthorized("Bad signature")
-        # Hand off the item to be processed by the queue
-        InboxMessage.objects.create(message=document)
-        return HttpResponse(status=202)
-
-
-class Webfinger(View):
-    """
-    Services webfinger requests
-    """
-
-    def get(self, request):
-        resource = request.GET.get("resource")
-        if not resource.startswith("acct:"):
-            raise Http404("Not an account resource")
-        handle = resource[5:].replace("testfedi", "feditest")
-        identity = by_handle_or_404(request, handle)
-        return JsonResponse(
-            {
-                "subject": f"acct:{identity.handle}",
-                "aliases": [
-                    identity.urls.view_short.full(),
-                ],
-                "links": [
-                    {
-                        "rel": "http://webfinger.net/rel/profile-page",
-                        "type": "text/html",
-                        "href": identity.urls.view_short.full(),
-                    },
-                    {
-                        "rel": "self",
-                        "type": "application/activity+json",
-                        "href": identity.actor_uri,
-                    },
-                ],
-            }
-        )