Update README instructions and set migration state in dev_cli db-gene…

…rate #425

README.md

@@ -329,30 +329,64 @@ a microservice that provides user authentication against an LDAP server and retu
 
 ### Migrations
 
-Migration scripts are located inside the `inventory_management_system/migrations/scripts`. See the
-`example_migration.py` for an example on how to implement one. Any new migrations added should be automatically picked
-up and shown via
+#### Adding a migration
+
+To add a migration first use
+
+```bash
+ims-migrate create <migration_name> <migration_description>
+```
+
+to create a new one inside the `inventory_management_system/migrations/scripts` directory. Then add the code necessary
+to perform the migration. See `_example_migration.py` for an example on how to implement one.
+
+#### Performing forward migrations
+
+Before performing a you can first check the current status of the database and any outstanding migrations using
 
 ```bash
-ims-migrate list
+ims-migrate status
 ```
 
-or
+or in Docker
 
 ```bash
 docker exec -it inventory_management_system_api_container ims-migrate list
 ```
 
-if running in Docker.
+Then to perform all outstanding migrations up to the latest one use
+
+```bash
+ims-migrate forward latest
+```
 
-To perform a migration you should use
+You may also specify a specific migration name to apply instead which will apply all migrations between the current
+applied one and the specified one. A prompt will be shown to ensure the migrations being applied are sensible.
+
+#### Performing backward migrations
+
+To revert the database by performing backwards migrations you can first use
 
 ```bash
-ims-migrate forward <migration_name>
+ims-migrate status
 ```
 
-To revert the same migration use
+to check the current status of the database and available migrations and then use
 
 ```bash
 ims-migrate backward <migration_name>
 ```
+
+to perform all backward migrations to get from the current database state back to the state prior to the chosen
+migration name (i.e. it also performs the backward migration for the given migration name).
+
+#### Forcing migration state
+
+If for some reason the migration state is different to what you expect it may be forced via
+
+```bash
+ims-migrate set <migration_name>
+```
+
+This is already set to `latest` automatically when using the `dev_cli` to regenerate mock data so that the dump retains
+the expected state.

inventory_management_system_api/migrations/script.py

@@ -5,6 +5,7 @@
 import logging
 import sys
 from abc import ABC, abstractmethod
+from typing import Optional
 
 from inventory_management_system_api.core.database import get_database
 from inventory_management_system_api.migrations.core import (
@@ -23,17 +24,30 @@
 database = get_database()
 
 
-def check_user_sure() -> bool:
+def check_user_sure(message: Optional[str] = None, skip: bool = False) -> bool:
     """
     Asks user if they are sure action should proceed and exits if not.
 
+    :param message: Message to accompany the check.
+    :param skip: Whether to skip printing out the message and performing the check.
     :return: Whether user is sure.
     """
 
+    if skip:
+        return True
+
+    print(message)
+    print()
     answer = input("Are you sure you wish to proceed? ")
     return answer in ("y", "yes")
 
 
+def add_skip_args(parser: argparse.ArgumentParser):
+    """Adds common arguments for skipping user prompts."""
+
+    parser.add_argument("--yes", "-y", help="Specify to skip all are you sure prompts", action="store_true")
+
+
 class SubCommand(ABC):
     """Base class for a sub command."""
 
@@ -198,6 +212,8 @@ def __init__(self):
     def setup(self, parser: argparse.ArgumentParser):
         parser.add_argument("name", help="Name of the last migration the database currently matches.")
 
+        add_skip_args(parser)
+
     def run(self, args: argparse.Namespace):
         available_migrations = find_available_migrations()
 
@@ -206,10 +222,10 @@ def run(self, args: argparse.Namespace):
         except ValueError:
             sys.exit(f"Migration '{args.name}' was not found in the available list of migrations")
 
-        print(f"This operation will forcibly set the latest migration to '{available_migrations[end_index]}'")
-        print()
-
-        if check_user_sure():
+        if check_user_sure(
+            message=f"This operation will forcibly set the latest migration to '{available_migrations[end_index]}'",
+            skip=args.yes,
+        ):
             set_previous_migration(available_migrations[end_index])
 
 

scripts/dev_cli.py

@@ -234,6 +234,10 @@ def run(self, args: argparse.Namespace):
                 generate_mock_data()
             except ImportError:
                 logging.error("Failed to find generate_mock_data.py")
+
+            logging.info("Ensuring previous migration is set to latest...")
+            run_command(["ims-migrate", "set", "latest", "-y"])
+
             if args.dump:
                 logging.info("Dumping output...")
                 # Dump output again