Implement the person endpoint.

GET /@<username>

It returns the activitystream representation of a user (Person).

activitypub/activities/__init__.py

@@ -0,0 +1,2 @@
+from .objects import *
+

activitypub/activities/errors.py

@@ -0,0 +1,8 @@
+class ASDecodeError(Exception):
+    pass
+
+class ASTypeError(Exception):
+    pass
+
+class ASValidateException(Exception):
+    pass

activitypub/activities/objects.py

@@ -0,0 +1,108 @@
+import json
+from activitypub.activities import errors
+
+class Object(object):
+    attributes = ["type", "id", "name", "to"]
+    type = "Object"
+
+    @classmethod
+    def from_json(cls, json):
+        return Object(**json)
+
+    def __init__(self, obj=None, **kwargs):
+        if obj:
+            self.__init__(**obj.to_activitystream())
+        for key in self.attributes:
+            if key == "type":
+                continue
+            
+            value = kwargs.get(key)
+            if value is None:
+                continue
+            
+            if isinstance(value, dict) and value.get("type"):
+                value = as_activitystream(value)
+            self.__setattr__(key, value)
+
+    def __str__(self):
+        content = json.dumps(self, default=encode_activitystream)
+        return "<{type}: {content}>".format(type=self.type,content=content)
+
+    def to_json(self, context=False):
+        values = {}
+        for attribute in self.attributes:
+            value = getattr(self, attribute, None)
+            if value is None:
+                continue
+            if isinstance(value, Object):
+                value = value.to_json()
+            # if getattr(value, "__iter__", None):
+            #     value = [item.to_json() for item in value]
+            values[attribute] = value
+        to = values.get("to")
+        if isinstance(to, str):
+            values["to"] = [to]
+        elif getattr(to, "__iter__", None):
+            values["to"] = []
+            for item in to:
+                if isinstance(item, str):
+                    values["to"].append(item)
+                if isinstance(item, Object):
+                    values["to"].append(item.id)
+
+        if context:
+            values["@context"] = "https://www.w3.org/ns/activitystreams"
+        return values
+
+    def to_activitystream(self):
+        return self
+
+class Actor(Object):
+
+    attributes = Object.attributes + [
+        "target",
+
+        "preferredUsername",
+        "following",
+        "followers",
+        "outbox",
+        "inbox",
+    ]
+    type = "Actor"
+
+    def send(self, activity):
+        res = requests.post(self.inbox, json=activity.to_json(context=True))
+        if res.status_code != 200:
+            raise Exception
+
+class Person(Actor):
+
+    type = "Person"
+
+#########
+# Utils #
+#########
+
+ALLOWED_TYPES = {
+    "Object": Object,
+    "Actor": Actor,
+    "Person": Person,
+}
+
+def as_activitystream(obj):
+    type = obj.get("type")
+
+    if not type:
+        msg = "Invalid ActivityStream object, the type is missing"
+        raise errors.ASDecodeError(msg)
+    
+    if type in ALLOWED_TYPES:
+        return ALLOWED_TYPES[type](**obj)
+                       
+    raise errors.ASDecodeError("Invalid Type {0}".format(type))
+
+def encode_activitystream(obj):
+    if isinstance(obj, Object):
+        return obj.to_json()
+    raise errors.ASTypeError("Unknown ActivityStream Type")
+                      

activitypub/apps.py

@@ -0,0 +1,4 @@
+from django.apps import AppConfig
+
+class ActivityPubConfig(AppConfig):
+    name = 'activitypub'

activitypub/migrations/0001_initial.py

@@ -0,0 +1,23 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.3 on 2017-07-16 15:53
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Person',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=100)),
+            ],
+        ),
+    ]

activitypub/migrations/0002_person_username.py

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.3 on 2017-07-16 16:16
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+def usernames(apps, schema_editor):
+    Person = apps.get_model('activitypub', 'Person')
+
+    for person in Person.objects.all():
+        person.username = person.name
+        person.save()
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('activitypub', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='person',
+            name='username',
+            field=models.CharField(max_length=100, null=True),
+        ),
+        migrations.RunPython(usernames, reverse_code=migrations.RunPython.noop)
+    ]

activitypub/models.py

@@ -0,0 +1,63 @@
+from django.db.models import Model, ForeignKey, CharField, TextField, BooleanField
+from django.db.models import ManyToManyField
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+
+from django.conf import settings
+from django.urls import reverse
+
+def uri(name, *args):
+    domain = settings.ACTIVITYPUB_DOMAIN
+    path   = reverse(name, args=args)
+    return "http://{domain}{path}".format(domain=domain, path=path)
+
+class URIs(object):
+
+    def __init__(self, **kwargs):
+        for attr, value in kwargs.items():
+            setattr(self, attr, value)
+
+class Person(Model):
+    ap_id     = TextField(null=True)
+    remote    = BooleanField(default=False)
+    
+    username  = CharField(max_length=100)
+    name      = CharField(max_length=100)
+    following = ManyToManyField('self', symmetrical=False, related_name='followers')
+
+    @property
+    def uris(self):
+        if self.remote:
+            return URIs(id=self.ap_id)
+        
+        return URIs(
+            id=uri("person", self.username),
+            following=uri("following", self.username),
+            followers=uri("followers", self.username),
+            outbox=uri("outbox", self.username),
+            inbox=uri("inbox", self.username),
+        )
+
+    def to_activitystream(self):
+        json = {
+            "id": self.uris.id,
+            "name": self.name,
+            "preferredUsername": self.username,
+        }
+
+        if not self.remote:
+            json.update({
+                "following": self.uris.following,
+                "followers": self.uris.followers,
+                "outbox": self.uris.outbox,
+                "inbox": self.uris.inbox,
+            })
+        return json
+
+@receiver(post_save, sender=Person)
+@receiver(post_save, sender=Note)
+def save_ap_id(sender, instance, created, **kwargs):
+    if created and not instance.remote:
+        instance.ap_id = instance.uris.id
+        instance.save()
+    

activitypub/settings.py

@@ -0,0 +1,124 @@
+"""
+Django settings for activitypub project.
+
+Generated by 'django-admin startproject' using Django 1.11.3.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/1.11/topics/settings/
+
+For the full list of settings and their values, see
+https://docs.djangoproject.com/en/1.11/ref/settings/
+"""
+
+import os
+
+# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
+BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+
+# Quick-start development settings - unsuitable for production
+# See https://docs.djangoproject.com/en/1.11/howto/deployment/checklist/
+
+# SECURITY WARNING: keep the secret key used in production secret!
+SECRET_KEY = '&@ie+jfg=w1_4jwq_!hkfa%r-%_j0%0sc(*fhhwqedx3(o+98p'
+
+# SECURITY WARNING: don't run with debug turned on in production!
+DEBUG = True
+
+ALLOWED_HOSTS = ["alice.local", "bob.local"]
+USE_X_FORWARDED_HOST = True
+ACTIVITYPUB_DOMAIN = "alice.local"
+
+
+# Application definition
+
+INSTALLED_APPS = [
+    'activitypub.apps.ActivityPubConfig',
+    'django.contrib.admin',
+    'django.contrib.auth',
+    'django.contrib.contenttypes',
+    'django.contrib.sessions',
+    'django.contrib.messages',
+    'django.contrib.staticfiles',
+]
+
+MIDDLEWARE = [
+    'django.middleware.security.SecurityMiddleware',
+    'django.contrib.sessions.middleware.SessionMiddleware',
+    'django.middleware.common.CommonMiddleware',
+    'django.middleware.csrf.CsrfViewMiddleware',
+    'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'django.contrib.messages.middleware.MessageMiddleware',
+    'django.middleware.clickjacking.XFrameOptionsMiddleware',
+]
+
+ROOT_URLCONF = 'activitypub.urls'
+
+TEMPLATES = [
+    {
+        'BACKEND': 'django.template.backends.django.DjangoTemplates',
+        'DIRS': [],
+        'APP_DIRS': True,
+        'OPTIONS': {
+            'context_processors': [
+                'django.template.context_processors.debug',
+                'django.template.context_processors.request',
+                'django.contrib.auth.context_processors.auth',
+                'django.contrib.messages.context_processors.messages',
+            ],
+        },
+    },
+]
+
+WSGI_APPLICATION = 'activitypub.wsgi.application'
+
+
+# Database
+# https://docs.djangoproject.com/en/1.11/ref/settings/#databases
+
+DATABASES = {
+    'default': {
+        'ENGINE': 'django.db.backends.sqlite3',
+        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
+    }
+}
+
+
+# Password validation
+# https://docs.djangoproject.com/en/1.11/ref/settings/#auth-password-validators
+
+AUTH_PASSWORD_VALIDATORS = [
+    {
+        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
+    },
+    {
+        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
+    },
+]
+
+
+# Internationalization
+# https://docs.djangoproject.com/en/1.11/topics/i18n/
+
+LANGUAGE_CODE = 'en-us'
+
+TIME_ZONE = 'UTC'
+
+USE_I18N = True
+
+USE_L10N = True
+
+USE_TZ = True
+
+
+
+# Static files (CSS, JavaScript, Images)
+# https://docs.djangoproject.com/en/1.11/howto/static-files/
+
+STATIC_URL = '/static/'

activitypub/urls.py

@@ -0,0 +1,10 @@
+from django.conf.urls import url
+from django.contrib import admin
+
+from activitypub.views import person, note, new_note, notes, inbox, outbox
+from activitypub.views import followers, noop
+
+urlpatterns = [
+    url(r'^@([^/]+)$', person, name="person"),
+    url(r'^admin/', admin.site.urls),
+]

activitypub/views.py

@@ -0,0 +1,17 @@
+from urllib.parse import urlparse
+import json
+import requests
+
+from django.http import JsonResponse, HttpResponseRedirect, HttpResponseNotAllowed
+from django.urls import reverse
+from django.shortcuts import get_object_or_404, render
+from django.views.decorators.csrf import csrf_exempt
+
+from activitypub.models import Person, Note
+from activitypub import activities
+from activitypub.activities import as_activitystream
+
+def person(request, username):
+    person = get_object_or_404(Person, username=username)
+    return JsonResponse(activities.Person(person).to_json(context=True))
+

activitypub/wsgi.py

@@ -0,0 +1,16 @@
+"""
+WSGI config for activitypub project.
+
+It exposes the WSGI callable as a module-level variable named ``application``.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/1.11/howto/deployment/wsgi/
+"""
+
+import os
+
+from django.core.wsgi import get_wsgi_application
+
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "activitypub.settings")
+
+application = get_wsgi_application()

manage.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+import os
+import sys
+
+if __name__ == "__main__":
+    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "activitypub.settings")
+    try:
+        from django.core.management import execute_from_command_line
+    except ImportError:
+        # The above import may fail for some other reason. Ensure that the
+        # issue is really that Django is missing to avoid masking other
+        # exceptions on Python 2.
+        try:
+            import django
+        except ImportError:
+            raise ImportError(
+                "Couldn't import Django. Are you sure it's installed and "
+                "available on your PYTHONPATH environment variable? Did you "
+                "forget to activate a virtual environment?"
+            )
+        raise
+    execute_from_command_line(sys.argv)