refactor(rest_db): allow more local customization

* devs may or may not want to reset their local DB
* devs may want to change which DB file is targeted
* devs may want to change which fixture file is loaded

update docs to reflect these changes

Author: thekaveman

.env.sample

@@ -1,6 +1,12 @@
 DJANGO_SUPERUSER_USERNAME=benefits-admin
 DJANGO_SUPERUSER_EMAIL=[email protected]
 DJANGO_SUPERUSER_PASSWORD=superuser12345!
+
+DJANGO_DB_RESET=true
+DJANGO_DB_DIR=.
+DJANGO_DB_FILE=django.db
+DJANGO_DB_FIXTURES="benefits/core/migrations/local_fixtures.json"
+
 testsecret=Hello from the local environment!
 auth_provider_client_id=benefits-oauth-client-id
 courtesy_card_verifier_api_auth_key=server-auth-token

benefits/settings.py

@@ -166,7 +166,7 @@ def RUNTIME_ENVIRONMENT():
 DATABASES = {
     "default": {
         "ENGINE": "django.db.backends.sqlite3",
-        "NAME": os.path.join(DATABASE_DIR, "django.db"),
+        "NAME": os.path.join(DATABASE_DIR, os.environ.get("DJANGO_DB_FILE", "django.db")),
     }
 }
 

bin/reset_db.sh

@@ -1,25 +1,35 @@
 #!/usr/bin/env bash
-set -eux
-
-# remove database file
-
-# construct the path to the database file from environment or default
-DB_DIR="${DJANGO_DB_DIR:-.}"
-DB_FILE="${DB_DIR}/django.db"
-
-# -f forces the delete (and avoids an error when the file doesn't exist)
-rm -f "${DB_FILE}"
-
-# run database migrations and other initialization
-
-bin/init.sh
-
-# create a superuser account for backend admin access
-# set username, email, and password using environment variables
-# DJANGO_SUPERUSER_USERNAME, DJANGO_SUPERUSER_EMAIL, and DJANGO_SUPERUSER_PASSWORD
-
-python manage.py createsuperuser --no-input
-
-# load sample data fixtures
-
-python manage.py loaddata benefits/core/migrations/local_fixtures.json
+set -ex
+
+# whether to reset database file, defaults to true
+DB_RESET="${DJANGO_DB_RESET:-true}"
+# optional fixtures to import
+FIXTURES="${DJANGO_DB_FIXTURES}"
+
+if [[ $DB_RESET = true ]]; then
+    # construct the path to the database file from environment or default
+    DB_DIR="${DJANGO_DB_DIR:-.}"
+    DB_FILE="${DJANGO_DB_FILE:-django.db}"
+    DB_PATH="${DB_DIR}/${DB_FILE}"
+
+    rm -f "${DB_PATH}"
+
+    # run database migrations and other initialization
+    bin/init.sh
+
+    # create a superuser account for backend admin access
+    # set username, email, and password using environment variables
+    # DJANGO_SUPERUSER_USERNAME, DJANGO_SUPERUSER_EMAIL, and DJANGO_SUPERUSER_PASSWORD
+    python manage.py createsuperuser --no-input
+else
+    echo "DB_RESET is false, skipping"
+fi
+
+valid_fixtures=$( echo $FIXTURES | grep -e fixtures\.json$ )
+
+if [[ -n "$valid_fixtures" ]]; then
+    # load data fixtures
+    python manage.py loaddata "$FIXTURES"
+else
+    echo "No JSON fixtures to load"
+fi

docs/configuration/data.md

@@ -1,23 +1,24 @@
 # Configuration data
 
-!!! example "Data migration file"
+!!! example "Sample data fixtures"
 
-    [`benefits/core/migrations/0002_data.py`][data-migration]
+    [`benefits/core/migrations/local_fixtures.json`][sample-fixtures]
 
 !!! tldr "Django docs"
 
     [How to provide initial data for models][django-load-initial-data]
 
 ## Introduction
 
-Django [data migrations](https://docs.djangoproject.com/en/4.0/topics/migrations/#data-migrations) are used to load the database with instances of the app's model classes, defined in [`benefits/core/models.py`][core-models].
+The app's model classes are defined in [`benefits/core/models.py`][core-models].
 
 Migrations are run as the application starts up. See the [`bin/init.sh`][init] script.
 
 The sample values provided in the repository are sufficient to run the app locally and interact with e.g. the sample Transit
-Agencies.
+Agencies. [Django fixtures][django-fixtures] are used to load the database with sample data when running locally.
 
-During the [deployment](../deployment/README.md) process, environment-specific values are set in environment variables and are read by the data migration file to build that environment's configuration database. See the [data migration file][data-migration] for the environment variable names.
+During the [deployment](../deployment/README.md) process, some environment-specific values are set in environment variables and
+read dynamically at runtime. Most configuration values are managed directly in the Django Admin interface at the `/admin` endpoint.
 
 ## Sample data
 
@@ -37,32 +38,24 @@ Some configuration data is not available with the samples in the repository:
 - Payment processor configuration for the enrollment phase
 - Amplitude configuration for capturing analytics events
 
-### Sample transit agency: `ABC`
+## Rebuilding the configuration database locally
 
-- Presents the user a choice between two different eligibility pathways
-- One eligibility verifier requires authentication
-- One eligibility verifier does not require authentication
+A local Django database will be initialized upon first startup of the devcontainer.
 
-### Sample transit agency: `DefTL`
-
-- Single eligibility pathway, no choice presented to the user
-- Eligibility verifier does not require authentication
-
-## Building the configuration database
-
-When the data migration changes, the configuration database needs to be rebuilt.
-
-The file is called `django.db` and the following commands will rebuild it.
-
-Run these commands from within the repository root, inside the devcontainer:
+To rebuild the local Django database, run the [`bin/reset_db.sh`][reset-db] script from within the repository root,
+inside the devcontainer:
 
 ```bash
-bin/init.sh
+bin/reset_db.sh
 ```
 
+See the [Django Environment Variables](environment-variables.md#django) section for details about how to configure the local
+database rebuild.
+
 [core-models]: https://github.com/cal-itp/benefits/blob/dev/benefits/core/models.py
-[django-load-initial-data]: https://docs.djangoproject.com/en/4.0/howto/initial-data/
+[django-fixtures]: https://docs.djangoproject.com/en/5.0/topics/db/fixtures/
+[django-load-initial-data]: https://docs.djangoproject.com/en/5.0/howto/initial-data/
 [eligibility-server]: https://docs.calitp.org/eligibility-server
-[data-migration]: https://github.com/cal-itp/benefits/tree/dev/benefits/core/migrations/0002_data.py
-[helper-migration]: https://github.com/cal-itp/benefits/tree/dev/benefits/core/migrations/0003_data_migration_order.py
 [init]: https://github.com/cal-itp/benefits/blob/dev/bin/init.sh
+[reset-db]: https://github.com/cal-itp/benefits/blob/dev/bin/reset_db.sh
+[sample-fixtures]: https://github.com/cal-itp/benefits/tree/dev/benefits/core/migrations/local_fixtures.json

docs/configuration/environment-variables.md

@@ -2,7 +2,8 @@
 
 The first steps of the Getting Started guide mention [creating an `.env` file][getting-started_create-env].
 
-The sections below outline in more detail the application environment variables that you may want to override, and their purpose. In App Service, this is more generally called the ["configuration"][app-service-config].
+The sections below outline in more detail the application environment variables that you may want to override, and their purpose.
+In Azure App Services, this is more generally called the ["configuration"][app-service-config].
 
 See other topic pages in this section for more specific environment variable configurations.
 
@@ -71,6 +72,39 @@ writable by the Django process._
 
 By default, the base project directory (i.e. the root of the repository).
 
+### `DJANGO_DB_FILE`
+
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
+The name of the Django database file to use locally (during both normal app startup and for resetting the database).
+
+By default, `django.db`.
+
+### `DJANGO_DB_FIXTURES`
+
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
+A path, relative to the repository root, of Django data fixtures to load when resetting the database.
+
+The file must end in `fixtures.json` for the script to process it correctly.
+
+By default, `benefits/core/migrations/local_fixtures.json`.
+
+### `DJANGO_DB_RESET`
+
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
+Boolean:
+
+- `True` (default): deletes the existing database file and runs fresh Django migrations.
+- `False`: Django uses the existing database file.
+
 ### `DJANGO_DEBUG`
 
 !!! warning "Deployment configuration"
@@ -79,7 +113,7 @@ By default, the base project directory (i.e. the root of the repository).
 
 !!! tldr "Django docs"
 
-    [Settings: `DEBUG`](https://docs.djangoproject.com/en/4.0/ref/settings/#debug)
+    [Settings: `DEBUG`](https://docs.djangoproject.com/en/5.0/ref/settings/#debug)
 
 Boolean:
 
@@ -128,14 +162,26 @@ Django's primary secret, keep this safe!
 
 ### `DJANGO_SUPERUSER_EMAIL`
 
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
 The email address of the Django Admin superuser created when resetting the database.
 
 ### `DJANGO_SUPERUSER_PASSWORD`
 
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
 The password of the Django Admin superuser created when resetting the database.
 
 ### `DJANGO_SUPERUSER_USERNAME`
 
+!!! info "Local configuration"
+
+    This setting only affects the app running on localhost
+
 The username of the Django Admin superuser created when resetting the database.
 
 ### `DJANGO_TRUSTED_ORIGINS`