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main.py
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main.py
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import json
from fastapi import FastAPI, Depends, HTTPException, status, Request, Response
from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
from fastapi.responses import JSONResponse, StreamingResponse
from pymongo import MongoClient
from pydantic import BaseModel, Field, HttpUrl, EmailStr
from typing import Optional, List, Dict, Any, Union
from pydantic_core import Url
import uvicorn
import datetime as dt
from datetime import datetime, timedelta
import requests
import base64
from starlette.middleware.base import BaseHTTPMiddleware
import os
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import rsa, padding
from dotenv import load_dotenv
from rdflib import Graph, Namespace
from rdflib.plugin import register, Parser, Serializer
import jwt
from passlib.context import CryptContext
load_dotenv()
def load_key(env_var_name, is_pem=True, is_private=True):
key_data = os.getenv(env_var_name)
if not is_pem:
return key_data
if not key_data:
raise ValueError(f"{env_var_name} environment variable is not set")
# Check if the key_data is a file path
if os.path.isfile(key_data):
with open(key_data, "rb") as key_file:
key_data = key_file.read()
else:
key_data = key_data.encode()
try:
if is_private:
return serialization.load_pem_private_key(key_data, password=None)
else:
return serialization.load_pem_public_key(key_data)
except ValueError:
# If it's not a PEM, it might be a plain secret key
return key_data.decode()
# Define ActivityStreams namespace
AS = Namespace("https://www.w3.org/ns/activitystreams#")
app = FastAPI()
SERVER_PRIVATE_KEY = load_key("SERVER_PRIVATE_KEY")
HS256_SECRET_KEY = load_key("HS256_SECRET_KEY", is_pem=False)
RS256_PUBLIC_KEY = load_key("RS256_PUBLIC_KEY", is_private=False)
RS256_PRIVATE_KEY = load_key("RS256_PRIVATE_KEY")
JWT_ALGORITHM = os.getenv("JWT_ALGORITHM", "HS256")
ACCESS_TOKEN_EXPIRE_MINUTES = 30
# Register JSON-LD plugin
register("json-ld", Parser, "rdflib_jsonld.parser", "JsonLDParser")
register("json-ld", Serializer, "rdflib_jsonld.serializer", "JsonLDSerializer")
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")
MONGO_URL = os.getenv("MONGO_URL")
if not MONGO_URL:
raise ValueError("MONGO_URL environment variable is not set")
client = MongoClient(MONGO_URL)
db = client["solanatribe"]
BASE_URL = os.getenv("BASE_URL")
if not BASE_URL:
raise ValueError("BASE_URL environment variable is not set")
class PublicKey(BaseModel):
id: str
owner: str
publicKeyPem: str
class Actor(BaseModel):
context: List[str] = Field(
default=[
"https://www.w3.org/ns/activitystreams",
"https://w3id.org/security/v1",
],
alias="@context",
)
type: str
id: HttpUrl
inbox: HttpUrl
outbox: HttpUrl
followers: HttpUrl
following: HttpUrl
liked: HttpUrl
streams: List[HttpUrl]
preferredUsername: str
name: Optional[str] = None
summary: Optional[str] = None
publicKey: PublicKey
icon: Optional[HttpUrl] = None
image: Optional[HttpUrl] = None
endpoints: Dict[str, HttpUrl]
def actor_to_dict(actor: Actor) -> dict:
actor_dict = actor.model_dump()
for key, value in actor_dict.items():
if isinstance(value, Url):
actor_dict[key] = str(value)
elif isinstance(value, dict):
for sub_key, sub_value in value.items():
if isinstance(sub_value, Url):
value[sub_key] = str(sub_value)
return actor_dict
class Source(BaseModel):
content: str
mediaType: str
class Activity(BaseModel):
context: List[str] = Field(
default=["https://www.w3.org/ns/activitystreams"], alias="@context"
)
type: str
id: Optional[HttpUrl] = None
actor: Union[HttpUrl, "Actor"]
object: Optional[Union[Dict[str, Any], HttpUrl, "Activity"]] = None
target: Optional[Union[Dict[str, Any], HttpUrl, "Activity"]] = None
result: Optional[Union[Dict[str, Any], HttpUrl, "Activity"]] = None
origin: Optional[Union[Dict[str, Any], HttpUrl, "Activity"]] = None
instrument: Optional[Union[Dict[str, Any], HttpUrl, "Activity"]] = None
to: Optional[List[Union[HttpUrl, "Actor"]]] = []
bto: Optional[List[Union[HttpUrl, "Actor"]]] = []
cc: Optional[List[Union[HttpUrl, "Actor"]]] = []
bcc: Optional[List[Union[HttpUrl, "Actor"]]] = []
audience: Optional[List[Union[HttpUrl, "Actor"]]] = []
published: Optional[datetime] = None
updated: Optional[datetime] = None
source: Optional[Source] = None
def activity_to_dict(activity: Activity) -> dict:
activity_dict = activity.model_dump(by_alias=True)
for key, value in activity_dict.items():
activity_dict[key] = process_value(value)
return activity_dict
def process_value(value):
if isinstance(value, BaseModel):
return value.model_dump()
elif isinstance(value, datetime):
return value.isoformat()
elif isinstance(value, list):
return [process_value(item) for item in value]
elif isinstance(value, dict):
return {k: process_value(v) for k, v in value.items()}
elif hasattr(value, "__str__"): # This will catch HttpUrl and similar types
return str(value)
return value
class Tombstone(BaseModel):
type: str = "Tombstone"
id: HttpUrl
formerType: Optional[str]
deleted: datetime
class OrderedCollection(BaseModel):
context: List[str] = Field(
default=["https://www.w3.org/ns/activitystreams"], alias="@context"
)
type: str = "OrderedCollection"
totalItems: int
first: HttpUrl
last: HttpUrl
class OrderedCollectionPage(BaseModel):
context: List[str] = Field(
default=["https://www.w3.org/ns/activitystreams"], alias="@context"
)
type: str = "OrderedCollectionPage"
id: HttpUrl
totalItems: int
orderedItems: List[Activity]
next: Optional[HttpUrl]
prev: Optional[HttpUrl]
class ContentNegotiationMiddleware(BaseHTTPMiddleware):
async def dispatch(self, request: Request, call_next):
accept = request.headers.get("Accept", "application/activity+json")
response = await call_next(request)
if "application/ld+json" in accept or "application/activity+json" in accept:
response.headers["Content-Type"] = (
'application/ld+json; profile="https://www.w3.org/ns/activitystreams"'
)
if isinstance(response, JSONResponse):
json_body = response.body
elif isinstance(response, StreamingResponse):
json_body = b"".join([chunk async for chunk in response.body_iterator])
else:
# For other response types, we might not be able to modify the content
return response
# Ensure json_body is a string
if isinstance(json_body, bytes):
json_body = json_body.decode("utf-8")
# Parse JSON
try:
json_data = json.loads(json_body)
except json.JSONDecodeError:
# If it's not valid JSON, return the original response
return response
# Convert to RDF graph
g = Graph()
g.parse(data=json.dumps(json_data), format="json-ld")
# Define ActivityStreams context
context = {
"@context": [
"https://www.w3.org/ns/activitystreams",
{"@language": "en"},
]
}
# Serialize back to JSON-LD, using ActivityStreams context
ld_body = g.serialize(format="json-ld", context=context, auto_compact=True)
return Response(
content=ld_body,
media_type='application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
)
return response
app.add_middleware(ContentNegotiationMiddleware)
def verify_password(plain_password, hashed_password):
return pwd_context.verify(plain_password, hashed_password)
def get_password_hash(password):
return pwd_context.hash(password)
def authenticate_user(username: str, password: str):
user = db.users.find_one({"username": username})
if not user:
return False
if not verify_password(password, user["hashed_password"]):
return False
return user
def create_access_token(
data: dict,
expires_delta: Optional[timedelta] = None,
algorithm: str = JWT_ALGORITHM,
):
to_encode = data.copy()
if expires_delta:
expire = datetime.now(dt.UTC) + expires_delta
else:
expire = datetime.now(dt.UTC) + timedelta(minutes=15)
to_encode.update({"exp": expire})
if algorithm == "HS256":
return jwt.encode(to_encode, str(HS256_SECRET_KEY), algorithm=algorithm)
elif algorithm == "RS256":
private_key = serialization.load_pem_private_key(
RS256_PRIVATE_KEY.encode(), password=None
)
return jwt.encode(to_encode, private_key, algorithm=algorithm)
else:
raise ValueError("Unsupported algorithm")
def get_current_user(token: str = Depends(oauth2_scheme)):
credentials_exception = HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Could not validate credentials",
headers={"WWW-Authenticate": "Bearer"},
)
try:
# Try HS256 first
try:
payload = jwt.decode(token, str(HS256_SECRET_KEY), algorithms=["HS256"])
except jwt.InvalidTokenError:
# If HS256 fails, try RS256
public_key = serialization.load_pem_public_key(RS256_PUBLIC_KEY.encode())
payload = jwt.decode(token, public_key, algorithms=["RS256"])
username: str = payload.get("sub")
if username is None:
raise credentials_exception
except jwt.PyJWTError:
raise credentials_exception
user = db.users.find_one({"username": username})
if user is None:
raise credentials_exception
return user
@app.post("/token")
async def login_for_access_token(
form_data: OAuth2PasswordRequestForm = Depends(), algorithm: str = JWT_ALGORITHM
):
user = authenticate_user(form_data.username, form_data.password)
if not user:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Incorrect username or password",
headers={"WWW-Authenticate": "Bearer"},
)
access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
access_token = create_access_token(
data={"sub": user["username"]},
expires_delta=access_token_expires,
algorithm=algorithm,
)
return {"access_token": access_token, "token_type": "bearer"}
@app.get("/objects/{object_id}/shares", response_model=OrderedCollection)
async def get_shares(object_id: str):
count = db.shares.count_documents({"object": object_id})
return OrderedCollection(
totalItems=count,
first=f"{BASE_URL}/objects/{object_id}/shares?page=1",
last=f"{BASE_URL}/objects/{object_id}/shares?page={(count-1)//20 + 1}",
)
@app.get("/objects/{object_id}/shares", response_model=OrderedCollectionPage)
async def get_shares_page(object_id: str, page: int = 1):
items = (
db.shares.find({"object": object_id})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
total = db.shares.count_documents({"object": object_id})
return OrderedCollectionPage(
id=f"{BASE_URL}/objects/{object_id}/shares?page={page}",
totalItems=total,
orderedItems=items,
next=f"{BASE_URL}/objects/{object_id}/shares?page={page+1}"
if page * 20 < total
else None,
prev=f"{BASE_URL}/objects/{object_id}/shares?page={page-1}"
if page > 1
else None,
)
@app.get("/.well-known/webfinger")
async def webfinger(resource: str):
username = resource.split("acct:")[1].split("@")[0]
actor = db.actors.find_one({"preferredUsername": username})
if not actor:
raise HTTPException(status_code=404, detail="User not found")
return {
"subject": f"acct:{username}@example.com",
"links": [
{
"rel": "self",
"type": "application/activity+json",
"href": f"{BASE_URL}/actors/{username}",
}
],
}
@app.get("/actors/{username}", response_model=Actor)
async def get_actor(username: str):
actor = db.actors.find_one({"preferredUsername": username})
if actor:
return Actor(**actor)
raise HTTPException(status_code=404, detail="Actor not found")
@app.get("/actors/{username}/inbox", response_model=OrderedCollection)
async def get_inbox(username: str, current_user: dict = Depends(get_current_user)):
if current_user["username"] != username:
raise HTTPException(status_code=403, detail="Forbidden")
count = db.inboxes.count_documents({"username": username})
return OrderedCollection(
totalItems=count,
first=f"{BASE_URL}/actors/{username}/inbox?page=1",
last=f"{BASE_URL}/actors/{username}/inbox?page={(count-1)//20 + 1}",
)
@app.get("/actors/{username}/inbox", response_model=OrderedCollectionPage)
async def get_inbox_page(
username: str, page: int = 1, current_user: dict = Depends(get_current_user)
):
if current_user["username"] != username:
raise HTTPException(status_code=403, detail="Forbidden")
items = (
db.inboxes.find({"username": username})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
total = db.inboxes.count_documents({"username": username})
return OrderedCollectionPage(
id=f"{BASE_URL}/actors/{username}/inbox?page={page}",
totalItems=total,
orderedItems=items,
next=f"{BASE_URL}/actors/{username}/inbox?page={page+1}"
if page * 20 < total
else None,
prev=f"{BASE_URL}/actors/{username}/inbox?page={page-1}" if page > 1 else None,
)
@app.post("/actors/{username}/inbox")
async def post_inbox(username: str, activity: Activity, request: Request):
verify_http_signature(request)
# De-duplicate activities
existing_activity = db.inboxes.find_one({"username": username, "id": activity.id})
if not existing_activity:
db.inboxes.insert_one(
{"activity": activity_to_dict(activity), "username": username}
)
process_activity(activity)
return Response(status_code=202)
@app.get(
"/actors/{username}/outbox",
response_model=Union[OrderedCollection, OrderedCollectionPage],
)
async def get_outbox(username: str, page: int = None):
total = db.outboxes.count_documents({"username": username})
if page is None:
# Return OrderedCollection when no page is specified
return OrderedCollection(
totalItems=total,
first=f"{BASE_URL}/actors/{username}/outbox?page=1",
last=f"{BASE_URL}/actors/{username}/outbox?page={(total-1)//20 + 1}",
)
else:
# Return OrderedCollectionPage when a page is specified
items = (
db.outboxes.find({"username": username})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
return OrderedCollectionPage(
id=f"{BASE_URL}/actors/{username}/outbox?page={page}",
totalItems=total,
orderedItems=items,
next=f"{BASE_URL}/actors/{username}/outbox?page={page+1}"
if page * 20 < total
else None,
prev=f"{BASE_URL}/actors/{username}/outbox?page={page-1}"
if page > 1
else None,
)
@app.post("/actors/{username}/outbox")
async def post_outbox(
username: str, activity: Activity, current_user: dict = Depends(get_current_user)
):
if current_user["username"] != username:
raise HTTPException(status_code=403, detail="Forbidden")
activity.id = activity.id or f"{BASE_URL}/activities/{username}/{id(activity)}"
activity.published = datetime.now(dt.UTC)
db.outboxes.insert_one(activity_to_dict(activity))
# Get followers
followers = db.followers.find_one({"username": username})
if followers:
forward_to_followers(activity)
return JSONResponse(status_code=201, content={"id": activity.id})
@app.get(
"/actors/{username}/followers",
response_model=Union[OrderedCollection, OrderedCollectionPage],
)
async def get_followers(username: str, page: int = None):
total = db.followers.count_documents({"username": username})
if page is None:
# Return OrderedCollection when no page is specified
return OrderedCollection(
totalItems=total,
first=f"{BASE_URL}/actors/{username}/followers?page=1",
last=f"{BASE_URL}/actors/{username}/followers?page={(total-1)//20 + 1}",
)
else:
# Return OrderedCollectionPage when a page is specified
items = (
db.followers.find({"username": username})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
return OrderedCollectionPage(
id=f"{BASE_URL}/actors/{username}/followers?page={page}",
totalItems=total,
orderedItems=items,
next=f"{BASE_URL}/actors/{username}/followers?page={page+1}"
if page * 20 < total
else None,
prev=f"{BASE_URL}/actors/{username}/followers?page={page-1}"
if page > 1
else None,
)
@app.get(
"/actors/{username}/following",
response_model=Union[OrderedCollection, OrderedCollectionPage],
)
async def get_following(username: str, page: int = None):
total = db.following.count_documents({"username": username})
if page is None:
# Return OrderedCollection when no page is specified
return OrderedCollection(
totalItems=total,
first=f"{BASE_URL}/actors/{username}/following?page=1",
last=f"{BASE_URL}/actors/{username}/following?page={(total-1)//20 + 1}",
)
else:
# Return OrderedCollectionPage when a page is specified
items = (
db.following.find({"username": username})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
return OrderedCollectionPage(
id=f"{BASE_URL}/actors/{username}/following?page={page}",
totalItems=total,
orderedItems=items,
next=f"{BASE_URL}/actors/{username}/following?page={page+1}"
if page * 20 < total
else None,
prev=f"{BASE_URL}/actors/{username}/following?page={page-1}"
if page > 1
else None,
)
async def deliver_activity(activity: Activity):
recipients = set(
activity.to + activity.cc + activity.bto + activity.bcc + activity.audience
)
for recipient in recipients:
if isinstance(recipient, str):
inbox = recipient
else:
inbox = recipient.inbox
try:
headers = create_signature("POST", inbox, activity.model_dump())
response = requests.post(
str(inbox), json=activity.model_dump(), headers=headers
)
response.raise_for_status()
except requests.HTTPError as e:
print(f"Failed to deliver activity to {inbox}: {e}")
def process_activity(activity: Activity):
if activity.type == "Create":
handle_create(activity)
elif activity.type == "Update":
handle_update(activity)
elif activity.type == "Delete":
handle_delete(activity)
elif activity.type == "Follow":
handle_follow(activity)
elif activity.type == "Accept":
handle_accept(activity)
elif activity.type == "Reject":
handle_reject(activity)
elif activity.type == "Add":
handle_add(activity)
elif activity.type == "Remove":
handle_remove(activity)
elif activity.type == "Like":
handle_like(activity)
elif activity.type == "Announce":
handle_announce(activity)
elif activity.type == "Undo":
handle_undo(activity)
elif activity.type == "Block":
handle_block(activity)
def handle_add(activity: Activity):
if isinstance(activity.object, dict) and isinstance(activity.target, str):
object_id = activity.object.get("id")
target_collection = activity.target
# Check if the target collection exists and is owned by the actor
collection = db.collections.find_one(
{"id": target_collection, "owner": activity.actor}
)
if collection:
# Add the object to the collection
db.collections.update_one(
{"id": target_collection}, {"$addToSet": {"items": object_id}}
)
# If the collection is an OrderedCollection, we might want to maintain order
if collection.get("type") == "OrderedCollection":
db.collections.update_one(
{"id": target_collection}, {"$push": {"orderedItems": object_id}}
)
def handle_remove(activity: Activity):
if isinstance(activity.object, dict) and isinstance(activity.target, str):
object_id = activity.object.get("id")
target_collection = activity.target
# Check if the target collection exists and is owned by the actor
collection = db.collections.find_one(
{"id": target_collection, "owner": activity.actor}
)
if collection:
# Remove the object from the collection
db.collections.update_one(
{"id": target_collection}, {"$pull": {"items": object_id}}
)
# If the collection is an OrderedCollection, remove from orderedItems as well
if collection.get("type") == "OrderedCollection":
db.collections.update_one(
{"id": target_collection}, {"$pull": {"orderedItems": object_id}}
)
def handle_follow(follow_activity: Activity):
follower = follow_activity.actor
followed = follow_activity.object
db.followers.update_one(
{"username": followed}, {"$addToSet": {"items": follower}}, upsert=True
)
accept_activity = Activity(
type="Accept", actor=followed, object=follow_activity.dict(), to=[follower]
)
deliver_activity(accept_activity)
def handle_unfollow(unfollow_activity: Activity):
follower = unfollow_activity.actor
followed = unfollow_activity.object
db.followers.update_one({"username": followed}, {"$pull": {"items": follower}})
def handle_object_activity(activity: Activity):
if activity.type == "Create":
handle_create(activity)
elif activity.type == "Update":
handle_update(activity)
elif activity.type == "Delete":
handle_delete(activity)
elif activity.type == "Like":
handle_like(activity)
elif activity.type == "Announce":
handle_announce(activity)
def handle_create(activity: Activity):
object_data = activity.object
if isinstance(object_data, dict):
object_id = object_data.get("id") or f"{BASE_URL}/objects/{id(object_data)}"
object_data["id"] = object_id
db.objects.insert_one(object_data)
forward_to_followers(activity)
def handle_update(activity: Activity):
object_data = activity.object
if isinstance(object_data, dict):
object_id = object_data.get("id")
if object_id:
existing_object = db.objects.find_one({"id": object_id})
if existing_object:
# Perform partial update
for key, value in object_data.items():
if value is None:
existing_object.pop(key, None)
else:
existing_object[key] = value
db.objects.replace_one({"id": object_id}, existing_object)
forward_to_followers(activity)
def handle_block(activity: Activity):
blocked_actor = activity.object
if isinstance(blocked_actor, str):
db.blocked.update_one(
{"username": activity.actor},
{"$addToSet": {"items": blocked_actor}},
upsert=True,
)
def handle_delete(activity: Activity):
object_id = activity.object
if isinstance(object_id, str):
existing_object = db.objects.find_one({"id": object_id})
if existing_object:
tombstone = Tombstone(
id=object_id,
formerType=existing_object.get("type"),
deleted=datetime.now(dt.UTC),
)
db.objects.replace_one({"id": object_id}, tombstone.model_dump())
forward_to_followers(activity)
def handle_like(activity: Activity):
liked_object = activity.object
if isinstance(liked_object, str):
db.liked.update_one(
{"username": activity.actor},
{"$addToSet": {"items": liked_object}},
upsert=True,
)
forward_to_followers(activity)
def handle_announce(activity: Activity):
announced_object = activity.object
if isinstance(announced_object, str):
db.announced.update_one(
{"username": activity.actor},
{"$addToSet": {"items": announced_object}},
upsert=True,
)
forward_to_followers(activity)
def handle_undo(activity: Activity):
if isinstance(activity.object, dict):
undone_activity_type = activity.object.get("type")
if undone_activity_type == "Follow":
handle_unfollow(activity)
elif undone_activity_type == "Like":
undo_like(activity)
elif undone_activity_type == "Announce":
undo_announce(activity)
def undo_like(activity: Activity):
liked_object = activity.object.get("object")
if isinstance(liked_object, str):
db.liked.update_one(
{"username": activity.actor}, {"$pull": {"items": liked_object}}
)
def undo_announce(activity: Activity):
announced_object = activity.object.get("object")
if isinstance(announced_object, str):
db.announced.update_one(
{"username": activity.actor}, {"$pull": {"items": announced_object}}
)
def handle_accept(activity: Activity):
if isinstance(activity.object, dict) and activity.object.get("type") == "Follow":
follower = activity.object.get("actor")
followed = activity.actor
db.following.update_one(
{"username": follower}, {"$addToSet": {"items": followed}}, upsert=True
)
def handle_reject(activity: Activity):
if isinstance(activity.object, dict) and activity.object.get("type") == "Follow":
follower = activity.object.get("actor")
followed = activity.actor
db.following.update_one({"username": follower}, {"$pull": {"items": followed}})
def forward_to_followers(activity: Activity):
actor_username = (
str(activity.actor).split("/")[-1]
if isinstance(activity.actor, Url)
else activity.actor.get("preferredUsername")
)
followers = db.followers.find_one({"username": actor_username})
if followers:
for follower in followers.get("items", []):
deliver_activity(activity, [follower])
async def verify_http_signature(request: Request):
signature_header = request.headers.get("Signature")
if not signature_header:
raise HTTPException(status_code=401, detail="Missing Signature header")
# Parse the Signature header to get the key_id
sig_parts = dict(part.split("=", 1) for part in signature_header.split(","))
key_id = sig_parts.get("keyId")
if not key_id:
raise HTTPException(status_code=401, detail="Invalid Signature header")
# Fetch the public key
actor_url = key_id.split("#")[0]
response = requests.get(actor_url, headers={"Accept": "application/activity+json"})
actor_data = response.json()
public_key_pem = actor_data.get("publicKey", {}).get("publicKeyPem")
if not public_key_pem:
raise HTTPException(status_code=401, detail="Unable to fetch public key")
public_key = serialization.load_pem_public_key(public_key_pem.encode())
# Verify the signature
if verify_signature(
public_key,
sig_parts["signature"],
request.method,
request.url.path,
request.headers,
):
return
else:
raise HTTPException(
status_code=401, detail=f"Invalid signature: {signature_header}"
)
def create_signature(private_key, method, path, headers):
signing_string = f"(request-target): {method.lower()} {path}\n"
signing_string += "\n".join(f"{k.lower()}: {v}" for k, v in headers.items())
signature = private_key.sign(
signing_string.encode(), padding.PKCS1v15(), hashes.SHA256()
)
return base64.b64encode(signature).decode()
def verify_signature(public_key, signature, method, path, headers):
signing_string = f"(request-target): {method.lower()} {path}\n"
signing_string += "\n".join(f"{k.lower()}: {v}" for k, v in headers.items())
try:
public_key.verify(
base64.b64decode(signature),
signing_string.encode(),
padding.PKCS1v15(),
hashes.SHA256(),
)
return True
except Exception:
return False
@app.post("/users", status_code=201)
async def create_user(username: str, email: EmailStr, password: str):
if db.users.find_one({"username": username}):
raise HTTPException(status_code=400, detail="Username already exists")
hashed_password = get_password_hash(password)
private_key, public_key = generate_key_pair()
public_key_pem = public_key.public_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PublicFormat.SubjectPublicKeyInfo,
).decode()
actor = Actor(
type="Person",
id=f"{BASE_URL}/actors/{username}",
inbox=f"{BASE_URL}/actors/{username}/inbox",
outbox=f"{BASE_URL}/actors/{username}/outbox",
followers=f"{BASE_URL}/actors/{username}/followers",
following=f"{BASE_URL}/actors/{username}/following",
liked=f"{BASE_URL}/actors/{username}/liked",
streams=[],
preferredUsername=username,
name=username,
summary=f"This is {username}'s account",
publicKey=PublicKey(
id=f"{BASE_URL}/actors/{username}#main-key",
owner=f"{BASE_URL}/actors/{username}",
publicKeyPem=public_key_pem,
),
endpoints={"sharedInbox": f"{BASE_URL}/shared_inbox"},
)
db.actors.insert_one(actor_to_dict(actor))
db.users.insert_one(
{
"username": username,
"email": email,
"hashed_password": hashed_password,
}
)
db.private_keys.insert_one(
{
"username": username,
"private_key": private_key.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.PKCS8,
encryption_algorithm=serialization.NoEncryption(),
).decode(),
}
)
return {"message": "User created successfully"}
def generate_key_pair():
private_key = rsa.generate_private_key(public_exponent=65537, key_size=2048)
public_key = private_key.public_key()
return private_key, public_key
@app.post("/shared_inbox")
async def shared_inbox(activity: Activity, request: Request):
verify_http_signature(request)
# Process the activity for all local users
local_users = db.actors.find().to_list(None)
for user in local_users:
username = user["preferredUsername"]
# De-duplicate activities
existing_activity = db.inboxes.find_one(
{"username": username, "id": activity.id}
)
if not existing_activity:
db.inboxes.insert_one(
{"activity": activity_to_dict(activity), "username": username}
)
process_activity(activity)
return Response(status_code=202)
@app.get(
"/actors/{username}/liked",
response_model=Union[OrderedCollection, OrderedCollectionPage],
)
async def get_liked(username: str, page: int = None):
total = db.liked.count_documents({"username": username})
if page is None:
# Return OrderedCollection when no page is specified
return OrderedCollection(
totalItems=total,
first=f"{BASE_URL}/actors/{username}/liked?page=1",
last=f"{BASE_URL}/actors/{username}/liked?page={(total-1)//20 + 1}",
)
else:
# Return OrderedCollectionPage when a page is specified
items = (
db.liked.find({"username": username})
.skip((page - 1) * 20)
.limit(20)
.to_list(20)
)
return OrderedCollectionPage(
id=f"{BASE_URL}/actors/{username}/liked?page={page}",