user creation flow with altcha verification

slopserver/common.py

@@ -0,0 +1 @@
+TEMP_HMAC_KEY = "0460de065912d0292df1e7422a5ed2dc362ed56d6bab64fe50b89957463061f3"

slopserver/db.py

@@ -51,3 +51,10 @@ def get_user(email, engine):
     with Session(engine) as session:
         user = session.scalar(query)
         return user
+
+def create_user(email, password_hash, engine):
+    user = User(email=email, password_hash=password_hash, email_verified=False)
+
+    with Session(engine) as session:
+        session.add(user)
+        session.commit()

slopserver/models.py

@@ -1,9 +1,13 @@
 from typing import Annotated
 from sqlmodel import Field, SQLModel, create_engine, Relationship
-from pydantic import AfterValidator, BaseModel
+from pydantic import AfterValidator, BaseModel, EmailStr, Json
+
+from altcha import Payload as AltchaPayload, verify_solution
 
 from urllib.parse import urlparse, ParseResult
 
+from slopserver.common import TEMP_HMAC_KEY
+
 NAMING_CONVENTION = {
     "ix": "ix_%(column_0_label)s",
     "uq": "uq_%(table_name)s_%(column_0_name)s",
@@ -36,7 +40,6 @@ class User(SQLModel, table=True):
     id: int | None = Field(default=None, primary_key=True)
     email: str = Field(index=True, unique=True)
     password_hash: str
-    salt: str
 
     email_verified: bool = Field(default=False)
 
@@ -56,7 +59,17 @@ def url_validator(urls: list[str]) -> list[ParseResult]:
             raise ValueError(f"couldn't parse '{url}' as a URL")
     return parsed_urls
 
+def altcha_validator(altcha_response: AltchaPayload):
+    verified = verify_solution(altcha_response, TEMP_HMAC_KEY)
+    if not verified[0]:
+        raise ValueError(f"altcha verification failed: {verified[1]}")
+    return None
 
 class SlopReport(BaseModel):
     """Accept reports of one or more slop page URLs"""
-    slop_urls: Annotated[list[str], AfterValidator(url_validator)]
+    slop_urls: Annotated[list[str], AfterValidator(url_validator)]
+
+class SignupForm(BaseModel):
+    email: EmailStr
+    password: str
+    altcha_response: Annotated[Json, AfterValidator(altcha_validator)]

slopserver/server.py

@@ -8,18 +8,23 @@
 - post report
 """
 from typing import Annotated
+from datetime import datetime, timedelta
+
 import uvicorn
 
-from fastapi import Depends, FastAPI, HTTPException
+from fastapi import Depends, FastAPI, Form, HTTPException
 from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
 
 from sqlalchemy import create_engine
 
 from pwdlib import PasswordHash
 
+from altcha import ChallengeOptions, create_challenge, verify_solution
+
 from slopserver.models import Domain, Path, User
-from slopserver.models import SlopReport
-from slopserver.db import select_slop, insert_slop, get_user
+from slopserver.models import SlopReport, SignupForm
+from slopserver.db import select_slop, insert_slop, get_user, create_user
+from slopserver.common import TEMP_HMAC_KEY
 
 app = FastAPI()
 
@@ -30,6 +35,7 @@ TEMP_SECRET = "5bcc778a96b090c3ac1d587bb694a060eaf7bdb5832365f91d5078faf1fff210"
 ALGO = "HS256"
 ACCESS_TOKEN_EXPIRE_MINUTES = 30
 
+
 password_hash = PasswordHash.recommended()
 
 
@@ -66,5 +72,26 @@ async def login(form_data: Annotated[OAuth2PasswordRequestForm, Depends()]):
     if not user:
         raise HTTPException(status_code=400, detail="Incorrect username or password")
 
+@app.post("/signup")
+async def signup_form(form_data: Annotated[SignupForm, Form()]):
+    # if we're here, form is validated including the altcha
+    # check for existing user with the given email
+    if get_user(form_data.email, TEMP_ENGINE):
+        # user already exists
+        raise HTTPException(status_code=409, detail="User already exists")
+
+    # create user
+    create_user(form_data.email, get_password_hash(form_data.password), TEMP_ENGINE)
+
+@app.get("/challenge")
+async def altcha_challenge():
+    options = ChallengeOptions(
+        expires=datetime.now() + timedelta(minutes=10),
+        max_number=100000,
+        hmac_key=TEMP_HMAC_KEY
+    )
+    challenge = create_challenge(options)
+    return challenge
+
 if __name__ == "__main__":
     uvicorn.run(app, host="0.0.0.0", port=8000)