src/auth/tokens.py : génération et validation des tokens (#73)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/auth/tokens.py

@@ -0,0 +1,61 @@
+import hashlib
+import secrets
+from datetime import datetime, timedelta, timezone
+
+from src.auth import db
+
+VERIFICATION_TTL_HOURS = 24
+RESET_TTL_HOURS = 1
+
+
+def hash_token(plain: str) -> str:
+    return hashlib.sha256(plain.encode("utf-8")).hexdigest()
+
+
+def _expires_at(hours: int) -> str:
+    return (datetime.now(timezone.utc) + timedelta(hours=hours)).isoformat()
+
+
+def create_verification_token(
+    user_id: int, expires_in_hours: int = VERIFICATION_TTL_HOURS
+) -> str:
+    plain = secrets.token_urlsafe(32)
+    db.create_email_verification_token(
+        hash_token(plain), user_id, _expires_at(expires_in_hours)
+    )
+    return plain
+
+
+def consume_verification_token(plain: str) -> int | None:
+    row = db.find_email_verification_token(hash_token(plain))
+    if row is None:
+        return None
+    user_id = row["user_id"]
+    db.delete_email_verification_tokens_for_user(user_id)
+    return user_id
+
+
+def create_password_reset_token(
+    user_id: int, expires_in_hours: int = RESET_TTL_HOURS
+) -> str:
+    db.delete_password_reset_tokens_for_user(user_id)
+    plain = secrets.token_urlsafe(32)
+    db.create_password_reset_token(
+        hash_token(plain), user_id, _expires_at(expires_in_hours)
+    )
+    return plain
+
+
+def consume_password_reset_token(plain: str) -> int | None:
+    row = db.find_password_reset_token(hash_token(plain))
+    if row is None:
+        return None
+    user_id = row["user_id"]
+    db.delete_password_reset_tokens_for_user(user_id)
+    return user_id
+
+
+def validate_password_reset_token(plain: str) -> int | None:
+    """Check token without consuming (used to render the reset form)."""
+    row = db.find_password_reset_token(hash_token(plain))
+    return row["user_id"] if row else None

tests/auth/test_tokens.py

@@ -0,0 +1,68 @@
+from src.auth import db
+from src.auth.tokens import (
+    consume_password_reset_token,
+    consume_verification_token,
+    create_password_reset_token,
+    create_verification_token,
+    hash_token,
+)
+
+
+def test_hash_token_is_stable():
+    t = "abc123"
+    assert hash_token(t) == hash_token(t)
+    assert hash_token(t) != hash_token("abc124")
+    assert len(hash_token(t)) == 64  # sha256 hex
+
+
+def test_create_verification_token_returns_plain_token(users_db_path):
+    db.init_schema()
+    uid = db.create_user("a@b.c", "h")
+    plain = create_verification_token(uid)
+    assert isinstance(plain, str)
+    assert len(plain) >= 32
+    # stocké en DB sous forme hashée
+    row = db.find_email_verification_token(hash_token(plain))
+    assert row is not None
+    assert row["user_id"] == uid
+
+
+def test_consume_verification_token_succeeds_once(users_db_path):
+    db.init_schema()
+    uid = db.create_user("a@b.c", "h")
+    plain = create_verification_token(uid)
+    user_id = consume_verification_token(plain)
+    assert user_id == uid
+    # usage unique : les tokens de cet user sont supprimés
+    assert consume_verification_token(plain) is None
+
+
+def test_consume_invalid_verification_token(users_db_path):
+    db.init_schema()
+    assert consume_verification_token("n-existe-pas") is None
+
+
+def test_verification_token_expires(users_db_path, monkeypatch):
+    db.init_schema()
+    uid = db.create_user("a@b.c", "h")
+    plain = create_verification_token(uid, expires_in_hours=-1)
+    assert consume_verification_token(plain) is None
+
+
+def test_create_password_reset_token_deletes_previous(users_db_path):
+    db.init_schema()
+    uid = db.create_user("a@b.c", "h")
+    old = create_password_reset_token(uid)
+    new = create_password_reset_token(uid)
+    # l'ancien a été supprimé
+    assert consume_password_reset_token(old) is None
+    # le nouveau fonctionne
+    assert consume_password_reset_token(new) == uid
+
+
+def test_consume_password_reset_token_is_single_use(users_db_path):
+    db.init_schema()
+    uid = db.create_user("a@b.c", "h")
+    plain = create_password_reset_token(uid)
+    assert consume_password_reset_token(plain) == uid
+    assert consume_password_reset_token(plain) is None