2 files changed, 67 insertions, 22 deletions

diff --git a/gn3/auth/authorisation/users/collections.py b/gn3/auth/authorisation/users/collections.py
index 9ddc138..2e2672c 100644
--- a/gn3/auth/authorisation/users/collections.py
+++ b/gn3/auth/authorisation/users/collections.py
@@ -1,30 +1,77 @@
 """Handle user collections."""
+import uuid
 import json
 
 from redis import Redis
+from email_validator import validate_email, EmailNotValidError
 
 from .models import User
 
+def __valid_email__(email:str) -> bool:
+    """Check for email validity."""
+    try:
+        validate_email(email, check_deliverability=True)
+    except EmailNotValidError as _enve:
+        return False
+    return True
+
+def __toggle_boolean_field__(
+        rconn: Redis, email: str, field: str):
+    """Toggle the valuen of a boolean field"""
+    mig_dict = json.loads(rconn.hget("migratable-accounts", email) or "{}")
+    if bool(mig_dict):
+        rconn.hset("migratable-accounts", email,
+                   {**mig_dict, field: not mig_dict.get(field, True)})
+
+def __build_email_uuid_bridge__(rconn: Redis):
+    """
+    Build a connection between new accounts and old user accounts.
+
+    The only thing that is common between the two is the email address,
+    therefore, we use that to link the two items.
+    """
+    old_accounts = {
+        account["email_address"]: {
+            "user_id": account["user_id"],
+            "collections-migrated": False,
+            "resources_migrated": False
+        } for account in (
+            acct for acct in
+            (json.loads(usr) for usr in rconn.hgetall("users").values())
+            if (bool(acct.get("email_address", False)) and
+                __valid_email__(acct["email_address"])))
+    }
+    if bool(old_accounts):
+        rconn.hset("migratable-accounts", mapping={
+            key: json.dumps(value) for key,value in old_accounts.items()
+        })
+    return old_accounts
+
+def __retrieve_old_accounts__(rconn: Redis) -> dict:
+    accounts = rconn.hgetall("migratable-accounts")
+    if accounts:
+        return {
+            key: json.loads(value) for key, value in accounts.items()
+        }
+    return __build_email_uuid_bridge__(rconn)
+
+def __retrieve_old_user_collections__(rconn: Redis, old_user_id: uuid.UUID) -> tuple:
+    """Retrieve any old collections relating to the user."""
+    return tuple(json.loads(rconn.hget("collections", old_user_id) or "[]"))
+
 def user_collections(rconn: Redis, user: User) -> tuple:
     """Retrieve current user collections."""
-    return tuple(json.loads(
+    collections = tuple(json.loads(
         rconn.hget("collections", str(user.user_id)) or
         "[]"))
-
-def old_user_collections(rconn: Redis, user: User) -> tuple:
-    """
-    Retrieve any old user collections and migrate them to new account.
-    """
-    collections = user_collections(rconn, user)
-    old_user_accounts = [
-        acct for acct in
-        (json.loads(usr) for usr in rconn.hgetall("users").values())
-        if acct.get("email_address", "") == user.email]
-    for account in old_user_accounts:
-        collections = collections + tuple(json.loads(
-            rconn.hget("collections", account["user_id"]) or "[]"))
-        rconn.hdel("collections", account["user_id"])
-
-    rconn.hset(
-        "collections", key=str(user.user_id), value=json.dumps(collections))
+    old_accounts = __retrieve_old_accounts__(rconn)
+    if (user.email in old_accounts and
+        not old_accounts[user.email]["collections-migrated"]):
+        old_user_id = old_accounts[user.email]["user_id"]
+        collections = tuple(set(collections + __retrieve_old_user_collections__(
+            rconn, uuid.UUID(old_user_id))))
+        rconn.hdel("collections", old_user_id)
+        __toggle_boolean_field__(rconn, user.email, "collections-migrated")
+        rconn.hset(
+            "collections", key=user.user_id, value=json.dumps(collections))
     return collections
diff --git a/gn3/auth/authorisation/users/views.py b/gn3/auth/authorisation/users/views.py
index 0a82de3..2b4230e 100644
--- a/gn3/auth/authorisation/users/views.py
+++ b/gn3/auth/authorisation/users/views.py
@@ -13,7 +13,7 @@ from gn3.auth.dictify import dictify
 from gn3.auth.db_utils import with_db_connection
 
 from .models import list_users
-from .collections import user_collections, old_user_collections
+from .collections import user_collections
 
 from ..groups.models import user_group as _user_group
 from ..resources.models import user_resources as _user_resources
@@ -180,6 +180,4 @@ def list_user_collections() -> Response:
     with (require_oauth.acquire("profile user") as the_token,
           Redis.from_url(current_app.config["REDIS_URI"],
                          decode_responses=True) as redisconn):
-        return jsonify(
-            user_collections(redisconn, the_token.user) or
-            old_user_collections(redisconn, the_token.user))
+        return jsonify(user_collections(redisconn, the_token.user))