1 files changed, 96 insertions, 0 deletions
diff --git a/jb/api/magic_token.py b/jb/api/magic_token.py
new file mode 100644
index 0000000..b60d5e9
--- /dev/null
+++ b/jb/api/magic_token.py
@@ -0,0 +1,96 @@
+import hashlib
+import secrets
+
+from fastapi import HTTPException, status
+from generalresearch.redis_helper import RedisConfig
+
+from jb.decorators import get_redis_config
+from jb.models.auth import AmtAccountLink
+
+MAGIC_TOKEN_PREFIX = "auth:magic:"
+AMT_ACCOUNT_LINK_TOKEN_PREFIX = "auth:amt-account-link:"
+MAGIC_TOKEN_TTL: int = 10 * 60  # 10 minutes, in seconds
+
+
+def redis_token_key(token: str, prefix: str = MAGIC_TOKEN_PREFIX) -> str:
+    # Redis never contains a usable credential, even if its keys are exposed.
+    digest = hashlib.sha256(token.encode("utf-8")).hexdigest()
+    return f"{prefix}{digest}"
+
+
+def create_magic_token(user_email: str, redis_config: RedisConfig | None = None) -> str:
+    """Create a short-lived, single-use token for a user.
+    The raw token can then be sent by email.
+    """
+    if not user_email or not user_email.strip():
+        raise ValueError("user_email must not be empty")
+
+    token = secrets.token_urlsafe(32)
+
+    if redis_config is None:
+        redis_config = get_redis_config()
+
+    redis_client = redis_config.create_redis_client()
+
+    redis_client.set(
+        redis_token_key(token),
+        user_email,
+        ex=MAGIC_TOKEN_TTL,
+    )
+    return token
+
+
+def consume_magic_token(token: str, redis_config: RedisConfig | None = None) -> str:
+    if redis_config is None:
+        redis_config = get_redis_config()
+
+    redis_client = redis_config.create_redis_client()
+
+    user_email = redis_client.getdel(redis_token_key(token))
+    if user_email is None:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired magic token",
+        )
+    return str(user_email)
+
+
+def create_amt_account_link_token(
+    email: str, amt_worker_id: str, redis_config: RedisConfig | None = None
+) -> str:
+    """Bind an email and AMT worker ID to an opaque, short-lived token."""
+    if redis_config is None:
+        redis_config = get_redis_config()
+
+    redis_client = redis_config.create_redis_client()
+
+    data = AmtAccountLink(
+        email=email,
+        amt_worker_id=amt_worker_id,
+    )
+    token = secrets.token_urlsafe(32)
+    redis_client.set(
+        redis_token_key(token, AMT_ACCOUNT_LINK_TOKEN_PREFIX),
+        data.model_dump_json(),
+        ex=MAGIC_TOKEN_TTL,
+    )
+    return token
+
+
+def consume_amt_account_link_token(
+    token: str, redis_config: RedisConfig | None = None
+) -> AmtAccountLink:
+    """Atomically consume and validate an AMT account-link token."""
+    if redis_config is None:
+        redis_config = get_redis_config()
+    redis_client = redis_config.create_redis_client()
+
+    raw_data = redis_client.getdel(
+        redis_token_key(token, AMT_ACCOUNT_LINK_TOKEN_PREFIX)
+    )
+    if raw_data is None:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired account-link token",
+        )
+    return AmtAccountLink.model_validate_json(raw_data)