feat: add migration command for mongo to mysql

README.rst

@@ -66,6 +66,81 @@ Optionally, you may checkout the `edly-io/forum_v2 <https://github.com/edly-io/e
     git checkout forum_v2
     tutor mounts add .
 
+Forum v2 Waffle Flag
+********************
+
+Description
+-----------
+The ``forum_v2.enable_mysql_backend`` waffle flag is used to toggle the use of the MySQL backend instead of the MongoDB backend.
+
+Details
+-------
+- **Toggle Name**: ``forum_v2.enable_mysql_backend``
+- **Implementation**: CourseWaffleFlag
+- **Default**: False
+- **Description**: Waffle flag to use the MySQL backend instead of Mongo backend.
+- **Use Cases**: temporary, open_edx
+- **Creation Date**: 2025-12-05
+- **Target Removal Date**: 2025-12-05
+
+Usage
+-----
+This waffle flag is automatically enabled for a course when the ``migrate_courses_to_mysql`` command is run for that course. It can also be manually added through the Django admin interface.
+
+Migration from MongoDB to MySQL backend:
+****************************************
+
+    python manage.py forum_migrate_course_from_mongodb_to_mysql
+
+Description
+-----------
+This command migrates data from MongoDB to MySQL for the specified courses.
+
+Usage
+-----
+To migrate data for a specific course(s), run the command with the course ID(s) as argument:
+
+   python manage.py forum_migrate_course_from_mongodb_to_mysql <course_id_1> <course_id_2>
+
+To migrate data for all courses, run the command with the ``all`` argument:
+
+   python manage.py forum_migrate_course_from_mongodb_to_mysql all
+
+What the command does
+---------------------
+The command performs the following steps:
+
+1. **Migrates user data**: Migrates user data from MongoDB to MySQL.
+2. **Migrates content data**: Migrates content data from MongoDB to MySQL.
+3. **Migrates read state data**: Migrates read state data from MongoDB to MySQL.
+4. **Enables waffle flag**: Enables the ``forum_v2.enable_mysql_backend`` waffle flag for the specified course.
+
+
+``python manage.py forum_delete_course_from_mongodb``
+
+Description
+-----------
+This command deletes course data from MongoDB for the specified courses.
+
+Usage
+-----
+To delete data for a specific course(s), run the command with the course ID(s) as an argument:
+
+   python manage.py forum_delete_course_from_mongodb <course_id_1> <course_id_2>
+
+To delete data for all courses, run the command with the ``all`` argument:
+
+   python manage.py forum_delete_course_from_mongodb all
+
+Options
+-------
+* ``--dry-run``: Perform a dry run without actually deleting data.
+
+Example
+-------
+
+   python manage.py forum_delete_course_from_mongodb <course_id> --dry-run
+
 .. Deploying
 .. *********
 

forum/backend.py

@@ -6,17 +6,26 @@
 from forum.backends.mysql.api import MySQLBackend
 
 
+def is_mysql_backend_enabled(course_id: str | None) -> bool:
+    """
+    Return True if mysql backend is enabled for the course.
+    """
+    try:
+        from forum.toggles import ENABLE_MYSQL_BACKEND  # pylint: disable=C0415
+    except ImportError:
+        return True
+
+    return ENABLE_MYSQL_BACKEND.is_enabled(course_id)
+
+
 def get_backend(
-    course_id: Optional[str] = "",
+    course_id: Optional[str] = None,
 ) -> Callable[[], MongoBackend | MySQLBackend]:
     """Return a factory function that lazily loads the backend API based on course_id."""
 
     def _get_backend() -> MongoBackend | MySQLBackend:
-        if not course_id:
-            # Lazy loading MongoBackend
-            return MongoBackend()
-        # TODO: add condition for course waffle flag.
-        # Lazy loading MySQLBackend
-        return MySQLBackend()
+        if is_mysql_backend_enabled(course_id):
+            return MySQLBackend()
+        return MongoBackend()
 
     return _get_backend

forum/management/commands/forum_delete_course_from_mongodb.py

@@ -0,0 +1,52 @@
+"""Deletion command for a course data in mongodb."""
+
+from typing import Any
+
+from django.core.management.base import BaseCommand, CommandParser
+
+from forum.migration_helpers import delete_course_data, get_all_course_ids
+from forum.mongo import get_database
+
+
+class Command(BaseCommand):
+    """Deletion command for a course data in mongodb."""
+
+    help = "Delete data from MongoDB for specific courses or all courses"
+
+    def add_arguments(self, parser: CommandParser) -> None:
+        parser.add_argument(
+            "courses", nargs="+", type=str, help="List of course IDs or `all`"
+        )
+        parser.add_argument(
+            "--dry-run",
+            action="store_true",
+            help="Perform a dry run without actually deleting data",
+        )
+
+    def handle(self, *args: str, **options: dict[str, Any]) -> None:
+        """Handle method for command."""
+        db = get_database()
+
+        courses: list[str] = list(options["courses"])
+        dry_run: bool = bool(options["dry_run"])
+
+        if dry_run:
+            self.stdout.write(
+                self.style.WARNING("Performing dry run. No data will be deleted.")
+            )
+
+        if "all" in courses:
+            courses = get_all_course_ids(db)
+
+        for course_id in courses:
+            self.stdout.write(f"Deleting data for course: {course_id}")
+            delete_course_data(db, course_id, dry_run, self.stdout)
+
+        if dry_run:
+            self.stdout.write(
+                self.style.SUCCESS("Dry run completed. No data was deleted.")
+            )
+        else:
+            self.stdout.write(
+                self.style.SUCCESS("Data deletion completed successfully")
+            )

forum/management/commands/forum_migrate_course_from_mongodb_to_mysql.py

@@ -0,0 +1,47 @@
+"""Migration command for courses from mongodb to mysql."""
+
+from typing import Any
+
+from django.core.management.base import BaseCommand
+from django.core.management.base import CommandParser
+
+from forum.migration_helpers import (
+    enable_mysql_backend_for_course,
+    get_all_course_ids,
+    migrate_content,
+    migrate_read_states,
+    migrate_users,
+)
+from forum.mongo import get_database
+
+
+class Command(BaseCommand):
+    """Migration command for courses from mongodb to mysql."""
+
+    help = "Migrate data from MongoDB to MySQL"
+
+    def add_arguments(self, parser: CommandParser) -> None:
+        """Add arguments to the command."""
+        parser.add_argument(
+            "courses", nargs="+", type=str, help="List of course IDs or `all`"
+        )
+
+    def handle(self, *args: str, **options: dict[str, Any]) -> None:
+        """Handle the command."""
+        db = get_database()
+
+        courses = list(options["courses"])
+        if "all" in courses:
+            courses = get_all_course_ids(db)
+
+        for course_id in courses:
+            self.stdout.write(f"Migrating data for course: {course_id}")
+            migrate_users(db, course_id)
+            migrate_content(db, course_id)
+            migrate_read_states(db, course_id)
+            enable_mysql_backend_for_course(course_id)
+            self.stdout.write(
+                f"Enabled mysql backend waffle flag for course {course_id}."
+            )
+
+        self.stdout.write(self.style.SUCCESS("Data migration completed successfully"))