Get Actor fetching and parsing working

6 files changed, 248 insertions, 15 deletions

diff --git a/users/migrations/0001_initial.py b/users/migrations/0001_initial.py
index e258d1b..5f9eacb 100644
--- a/users/migrations/0001_initial.py
+++ b/users/migrations/0001_initial.py
@@ -1,4 +1,4 @@
-# Generated by Django 4.1.3 on 2022-11-05 19:15
+# Generated by Django 4.1.3 on 2022-11-05 23:50
 
 import functools
 
@@ -96,32 +96,50 @@ class Migration(migrations.Migration):
                 ),
                 ("handle", models.CharField(max_length=500, unique=True)),
                 ("name", models.CharField(blank=True, max_length=500, null=True)),
-                ("bio", models.TextField(blank=True, null=True)),
+                ("summary", models.TextField(blank=True, null=True)),
+                ("actor_uri", models.CharField(blank=True, max_length=500, null=True)),
                 (
-                    "profile_image",
+                    "profile_uri",
+                    models.CharField(blank=True, max_length=500, null=True),
+                ),
+                ("inbox_uri", models.CharField(blank=True, max_length=500, null=True)),
+                ("outbox_uri", models.CharField(blank=True, max_length=500, null=True)),
+                ("icon_uri", models.CharField(blank=True, max_length=500, null=True)),
+                ("image_uri", models.CharField(blank=True, max_length=500, null=True)),
+                (
+                    "icon",
                     models.ImageField(
+                        blank=True,
+                        null=True,
                         upload_to=functools.partial(
                             users.models.identity.upload_namer,
                             *("profile_images",),
                             **{},
-                        )
+                        ),
                     ),
                 ),
                 (
-                    "background_image",
+                    "image",
                     models.ImageField(
+                        blank=True,
+                        null=True,
                         upload_to=functools.partial(
                             users.models.identity.upload_namer,
                             *("background_images",),
                             **{},
-                        )
+                        ),
                     ),
                 ),
                 ("local", models.BooleanField()),
-                ("private_key", models.BinaryField(blank=True, null=True)),
-                ("public_key", models.BinaryField(blank=True, null=True)),
+                (
+                    "manually_approves_followers",
+                    models.BooleanField(blank=True, null=True),
+                ),
+                ("private_key", models.TextField(blank=True, null=True)),
+                ("public_key", models.TextField(blank=True, null=True)),
                 ("created", models.DateTimeField(auto_now_add=True)),
                 ("updated", models.DateTimeField(auto_now=True)),
+                ("fetched", models.DateTimeField(blank=True, null=True)),
                 ("deleted", models.DateTimeField(blank=True, null=True)),
                 (
                     "users",
@@ -131,4 +149,37 @@ class Migration(migrations.Migration):
                 ),
             ],
         ),
+        migrations.CreateModel(
+            name="Follow",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("note", models.TextField(blank=True, null=True)),
+                ("created", models.DateTimeField(auto_now_add=True)),
+                ("updated", models.DateTimeField(auto_now=True)),
+                (
+                    "source",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="outbound_follows",
+                        to="users.identity",
+                    ),
+                ),
+                (
+                    "target",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="inbound_follows",
+                        to="users.identity",
+                    ),
+                ),
+            ],
+        ),
     ]
diff --git a/users/models/__init__.py b/users/models/__init__.py
index 7032a81..ce69d1d 100644
--- a/users/models/__init__.py
+++ b/users/models/__init__.py
@@ -1,3 +1,4 @@
+from .follow import Follow  # noqa
 from .identity import Identity  # noqa
 from .user import User  # noqa
 from .user_event import UserEvent  # noqa
diff --git a/users/models/follow.py b/users/models/follow.py
new file mode 100644
index 0000000..e134f28
--- /dev/null
+++ b/users/models/follow.py
@@ -0,0 +1,23 @@
+from django.db import models
+
+
+class Follow(models.Model):
+    """
+    Tracks major events that happen to users
+    """
+
+    source = models.ForeignKey(
+        "users.Identity",
+        on_delete=models.CASCADE,
+        related_name="outbound_follows",
+    )
+    target = models.ForeignKey(
+        "users.Identity",
+        on_delete=models.CASCADE,
+        related_name="inbound_follows",
+    )
+
+    note = models.TextField(blank=True, null=True)
+
+    created = models.DateTimeField(auto_now_add=True)
+    updated = models.DateTimeField(auto_now=True)
diff --git a/users/models/identity.py b/users/models/identity.py
index 495b4a4..c20ef60 100644
--- a/users/models/identity.py
+++ b/users/models/identity.py
@@ -2,12 +2,17 @@ import base64
 import uuid
 from functools import partial
 
+import httpx
 import urlman
-from cryptography.hazmat.primitives import serialization
-from cryptography.hazmat.primitives.asymmetric import rsa
+from asgiref.sync import sync_to_async
+from cryptography.hazmat.primitives import hashes, serialization
+from cryptography.hazmat.primitives.asymmetric import padding, rsa
 from django.conf import settings
 from django.db import models
 from django.utils import timezone
+from django.utils.http import http_date
+
+from core.ld import LDDocument
 
 
 def upload_namer(prefix, instance, filename):
@@ -27,20 +32,31 @@ class Identity(models.Model):
     # The handle includes the domain!
     handle = models.CharField(max_length=500, unique=True)
     name = models.CharField(max_length=500, blank=True, null=True)
-    bio = models.TextField(blank=True, null=True)
+    summary = models.TextField(blank=True, null=True)
+
+    actor_uri = models.CharField(max_length=500, blank=True, null=True)
+    profile_uri = models.CharField(max_length=500, blank=True, null=True)
+    inbox_uri = models.CharField(max_length=500, blank=True, null=True)
+    outbox_uri = models.CharField(max_length=500, blank=True, null=True)
+    icon_uri = models.CharField(max_length=500, blank=True, null=True)
+    image_uri = models.CharField(max_length=500, blank=True, null=True)
 
-    profile_image = models.ImageField(upload_to=partial(upload_namer, "profile_images"))
-    background_image = models.ImageField(
-        upload_to=partial(upload_namer, "background_images")
+    icon = models.ImageField(
+        upload_to=partial(upload_namer, "profile_images"), blank=True, null=True
+    )
+    image = models.ImageField(
+        upload_to=partial(upload_namer, "background_images"), blank=True, null=True
     )
 
     local = models.BooleanField()
     users = models.ManyToManyField("users.User", related_name="identities")
+    manually_approves_followers = models.BooleanField(blank=True, null=True)
     private_key = models.TextField(null=True, blank=True)
     public_key = models.TextField(null=True, blank=True)
 
     created = models.DateTimeField(auto_now_add=True)
     updated = models.DateTimeField(auto_now=True)
+    fetched = models.DateTimeField(null=True, blank=True)
     deleted = models.DateTimeField(null=True, blank=True)
 
     @property
@@ -69,6 +85,128 @@ class Identity(models.Model):
         )
         self.save()
 
+    async def fetch_details(self):
+        if self.local:
+            raise ValueError("Cannot fetch local identities")
+        self.actor_uri = None
+        self.inbox_uri = None
+        self.profile_uri = None
+        # Go knock on webfinger and see what their address is
+        await self.fetch_webfinger()
+        # Fetch actor JSON
+        if self.actor_uri:
+            await self.fetch_actor()
+        self.fetched = timezone.now()
+        await sync_to_async(self.save)()
+
+    async def fetch_webfinger(self) -> bool:
+        async with httpx.AsyncClient() as client:
+            response = await client.get(
+                f"https://{self.domain}/.well-known/webfinger?resource=acct:{self.handle}",
+                headers={"Accept": "application/json"},
+            )
+        if response.status_code >= 400:
+            return False
+        data = response.json()
+        for link in data["links"]:
+            if (
+                link.get("type") == "application/activity+json"
+                and link.get("rel") == "self"
+            ):
+                self.actor_uri = link["href"]
+            elif (
+                link.get("type") == "text/html"
+                and link.get("rel") == "http://webfinger.net/rel/profile-page"
+            ):
+                self.profile_uri = link["href"]
+        return True
+
+    async def fetch_actor(self) -> bool:
+        async with httpx.AsyncClient() as client:
+            response = await client.get(
+                self.actor_uri,
+                headers={"Accept": "application/json"},
+            )
+            if response.status_code >= 400:
+                return False
+            data = response.json()
+            document = LDDocument(data)
+            for person in document.by_type(
+                "https://www.w3.org/ns/activitystreams#Person"
+            ):
+                self.name = person.get("https://www.w3.org/ns/activitystreams#name")
+                self.summary = person.get(
+                    "https://www.w3.org/ns/activitystreams#summary"
+                )
+                self.inbox_uri = person.get("http://www.w3.org/ns/ldp#inbox")
+                self.outbox_uri = person.get(
+                    "https://www.w3.org/ns/activitystreams#outbox"
+                )
+                self.manually_approves_followers = person.get(
+                    "https://www.w3.org/ns/activitystreams#manuallyApprovesFollowers'"
+                )
+                self.private_key = person.get(
+                    "https://w3id.org/security#publicKey"
+                ).get("https://w3id.org/security#publicKeyPem")
+                icon = person.get("https://www.w3.org/ns/activitystreams#icon")
+                if icon:
+                    self.icon_uri = icon.get(
+                        "https://www.w3.org/ns/activitystreams#url"
+                    )
+                image = person.get("https://www.w3.org/ns/activitystreams#image")
+                if image:
+                    self.image_uri = image.get(
+                        "https://www.w3.org/ns/activitystreams#url"
+                    )
+        return True
+
+    async def signed_request(self, host, method, path, document):
+        """
+        Delivers the document to the specified host, method, path and signed
+        as this user.
+        """
+        private_key = serialization.load_pem_private_key(
+            self.private_key,
+            password=None,
+        )
+        date_string = http_date(timezone.now().timestamp())
+        headers = {
+            "(request-target)": f"{method} {path}",
+            "Host": host,
+            "Date": date_string,
+        }
+        headers_string = " ".join(headers.keys())
+        signed_string = "\n".join(f"{name}: {value}" for name, value in headers.items())
+        signature = base64.b64encode(
+            private_key.sign(
+                signed_string,
+                padding.PSS(
+                    mgf=padding.MGF1(hashes.SHA256()),
+                    salt_length=padding.PSS.MAX_LENGTH,
+                ),
+                hashes.SHA256(),
+            )
+        )
+        del headers["(request-target)"]
+        headers[
+            "Signature"
+        ] = f'keyId="https://{settings.DEFAULT_DOMAIN}{self.urls.actor}",headers="{headers_string}",signature="{signature}"'
+        async with httpx.AsyncClient() as client:
+            return await client.request(
+                method,
+                "https://{host}{path}",
+                headers=headers,
+                data=document,
+            )
+
+    def validate_signature(self, request):
+        """
+        Attempts to validate the signature on an incoming request.
+        Returns False if the signature is invalid, None if it cannot be verified
+        as we do not have the key locally, or the name of the actor if it is valid.
+        """
+        pass
+
     def __str__(self):
         return self.name or self.handle
 
diff --git a/users/models/user.py b/users/models/user.py
index de51380..6435bf5 100644
--- a/users/models/user.py
+++ b/users/models/user.py
@@ -56,3 +56,9 @@ class User(AbstractBaseUser):
     @property
     def is_staff(self):
         return self.admin
+
+    def has_module_perms(self, module):
+        return self.admin
+
+    def has_perm(self, perm):
+        return self.admin
diff --git a/users/views/identity.py b/users/views/identity.py
index 63b7fb8..9f2a7f9 100644
--- a/users/views/identity.py
+++ b/users/views/identity.py
@@ -4,6 +4,7 @@ from django.contrib.auth.decorators import login_required
 from django.http import Http404, JsonResponse
 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
@@ -88,7 +89,7 @@ class Actor(View):
                 ],
                 "id": f"https://{settings.DEFAULT_DOMAIN}{identity.urls.actor}",
                 "type": "Person",
-                "preferredUsername": "alice",
+                "preferredUsername": identity.short_handle,
                 "inbox": f"https://{settings.DEFAULT_DOMAIN}{identity.urls.inbox}",
                 "publicKey": {
                     "id": f"https://{settings.DEFAULT_DOMAIN}{identity.urls.actor}#main-key",
@@ -99,6 +100,19 @@ class Actor(View):
         )
 
 
+@method_decorator(csrf_exempt, name="dispatch")
+class Inbox(View):
+    """
+    AP Inbox endpoint
+    """
+
+    def post(self, request, handle):
+        # Validate the signature
+        signature = request.META.get("HTTP_SIGNATURE")
+        print(signature)
+        print(request.body)
+
+
 class Webfinger(View):
     """
     Services webfinger requests