From 2f52d2c8464432d5f413488b234fe065824dab76 Mon Sep 17 00:00:00 2001
From: carsten <carsten@itkon.dk>
Date: Tue, 29 Sep 2026 12:15:36 +0200
Subject: [PATCH] =?UTF-8?q?Ret=20alembic-crash=20n=C3=A5r=20DATABASE=5FURL?=
 =?UTF-8?q?=20indeholder=20et=20bogstaveligt=20"%"?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

migrations/env.py brugte config.set_main_option() til at dele
databasens URL med alembic.ini — det kalder internt Pythons
configparser.set(), som fortolker "%" som sin egen
interpolations-syntaks og fejler på ethvert kodeord der indeholder
et procenttegn (fx fra en almindelig password-generator, eller
percent-encoded specialtegn i en URL).

Fundet under produktionsopsætning: brugerens Postgres-kodeord
indeholdt "%", hvilket crashede `alembic upgrade head` med
"ValueError: invalid interpolation syntax".

URL'en gemmes nu i config.attributes (en almindelig dict, ingen
configparser-fortolkning involveret) i stedet, og engine'en i
run_migrations_online bygges direkte med create_engine() i stedet
for engine_from_config() (som ellers ville læse URL'en tilbage via
configparser igen). Verificeret lokalt med både et normalt
DATABASE_URL og et med et bogstaveligt "%" i kodeordet.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 migrations/env.py | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/migrations/env.py b/migrations/env.py
index f788062..8b48389 100644
--- a/migrations/env.py
+++ b/migrations/env.py
@@ -2,7 +2,7 @@ import os
 import sys
 from logging.config import fileConfig
 
-from sqlalchemy import engine_from_config
+from sqlalchemy import create_engine
 from sqlalchemy import pool
 from sqlmodel import SQLModel
 
@@ -18,8 +18,11 @@ from app import models  # noqa: E402,F401  -- populates SQLModel.metadata via au
 config = context.config
 
 # Share one source of truth for the DB URL with the FastAPI app instead of
-# whatever placeholder sits in alembic.ini.
-config.set_main_option("sqlalchemy.url", get_settings().database_url)
+# whatever placeholder sits in alembic.ini. Stored in `config.attributes`
+# (a plain dict) rather than via set_main_option — that goes through
+# configparser's interpolation, which crashes on a literal "%" in the URL
+# (eg. from a percent-encoded special character in the password).
+config.attributes["sqlalchemy_url"] = get_settings().database_url
 
 # Interpret the config file for Python logging.
 # This line sets up loggers basically.
@@ -48,7 +51,7 @@ def run_migrations_offline() -> None:
     script output.
 
     """
-    url = config.get_main_option("sqlalchemy.url")
+    url = config.attributes["sqlalchemy_url"]
     context.configure(
         url=url,
         target_metadata=target_metadata,
@@ -67,11 +70,7 @@ def run_migrations_online() -> None:
     and associate a connection with the context.
 
     """
-    connectable = engine_from_config(
-        config.get_section(config.config_ini_section, {}),
-        prefix="sqlalchemy.",
-        poolclass=pool.NullPool,
-    )
+    connectable = create_engine(config.attributes["sqlalchemy_url"], poolclass=pool.NullPool)
 
     with connectable.connect() as connection:
         context.configure(