From 88aae4022664843366508020d934fe9a8d70e51d Mon Sep 17 00:00:00 2001
From: Simon Willison <swillison@gmail.com>
Date: Sun, 14 Mar 2021 09:30:49 -0700
Subject: [PATCH] Run tests against read-only 'dashboard' connection, refs #18

---
 conftest.py                     | 10 ++++++++++
 django_sql_dashboard/views.py   |  5 ++++-
 pytest_use_postgresql.py        |  1 +
 test_project/config/settings.py |  4 +++-
 4 files changed, 18 insertions(+), 2 deletions(-)
 create mode 100644 conftest.py

diff --git a/conftest.py b/conftest.py
new file mode 100644
index 0000000..99f73d3
--- /dev/null
+++ b/conftest.py
@@ -0,0 +1,10 @@
+import pytest
+
+
+@pytest.fixture(scope="session")
+def django_db_modify_db_settings():
+    from django.conf import settings
+
+    settings.DATABASES["dashboard"]["OPTIONS"] = {
+        "options": "-c default_transaction_read_only=on -c statement_timeout=100"
+    }
diff --git a/django_sql_dashboard/views.py b/django_sql_dashboard/views.py
index 6dfdf6d..61870cd 100644
--- a/django_sql_dashboard/views.py
+++ b/django_sql_dashboard/views.py
@@ -2,8 +2,9 @@
 import time
 
 from django.contrib.auth.decorators import permission_required
-from django.db import connection, transaction
+from django.db import connections, transaction
 from django.shortcuts import get_object_or_404, render
+from django.conf import settings
 
 from .models import Dashboard
 
@@ -18,6 +19,8 @@ def _dashboard_index(
     request, sql_queries, title=None, description=None, saved_dashboard=False
 ):
     query_results = []
+    alias = getattr(settings, "DASHBOARD_DB_ALIAS", "dashboard")
+    connection = connections[alias]
     with connection.cursor() as tables_cursor:
         tables_cursor.execute(
             """
diff --git a/pytest_use_postgresql.py b/pytest_use_postgresql.py
index d7fbfef..b04196f 100644
--- a/pytest_use_postgresql.py
+++ b/pytest_use_postgresql.py
@@ -12,6 +12,7 @@
 def pytest_load_initial_conftests(early_config, parser, args):
     os.environ["DJANGO_SETTINGS_MODULE"] = early_config.getini("DJANGO_SETTINGS_MODULE")
     settings.DATABASES["default"] = parse(_POSTGRESQL.url())
+    settings.DATABASES["dashboard"] = parse(_POSTGRESQL.url())
 
 
 def pytest_unconfigure(config):
diff --git a/test_project/config/settings.py b/test_project/config/settings.py
index c5f1e55..7f48c34 100644
--- a/test_project/config/settings.py
+++ b/test_project/config/settings.py
@@ -55,7 +55,9 @@
 WSGI_APPLICATION = "config.wsgi.application"
 
 
-DATABASES = {"default": dj_database_url.config()}
+DATABASES = {
+    "default": dj_database_url.config(),
+}
 
 # Password validation
 # https://docs.djangoproject.com/en/3.1/ref/settings/#auth-password-validators