Merge pull request 'Migration module' (#8) from migrations-branch-fix into master

Reviewed-on: https://git.selfprivacy.org/SelfPrivacy/selfprivacy-rest-api/pulls/8

selfprivacy_api/app.py

@@ -16,6 +16,8 @@ from selfprivacy_api.resources.services import services as api_services
 
 from selfprivacy_api.restic_controller.tasks import huey, init_restic
 
+from selfprivacy_api.migrations import run_migrations
+
 swagger_blueprint = get_swaggerui_blueprint(
     "/api/docs", "/api/swagger.json", config={"app_name": "SelfPrivacy API"}
 )
@@ -59,7 +61,7 @@ def create_app(test_config=None):
     def spec():
         if app.config["ENABLE_SWAGGER"] == "1":
             swag = swagger(app)
-            swag["info"]["version"] = "1.1.0"
+            swag["info"]["version"] = "1.1.1"
             swag["info"]["title"] = "SelfPrivacy API"
             swag["info"]["description"] = "SelfPrivacy API"
             swag["securityDefinitions"] = {
@@ -83,6 +85,7 @@ def create_app(test_config=None):
 if __name__ == "__main__":
     monkey.patch_all()
     created_app = create_app()
+    run_migrations()
     huey.start()
     init_restic()
     created_app.run(port=5050, debug=False)

selfprivacy_api/migrations/__init__.py

@@ -0,0 +1,31 @@
+from selfprivacy_api.utils import ReadUserData
+from selfprivacy_api.migrations.fix_nixos_config_branch import FixNixosConfigBranch
+
+migrations = [FixNixosConfigBranch()]
+
+
+def run_migrations():
+    """
+    Go over all migrations. If they are not skipped in userdata file, run them
+    if the migration needed.
+    """
+    with ReadUserData() as data:
+        if "api" not in data:
+            skipped_migrations = []
+        elif "skippedMigrations" not in data["api"]:
+            skipped_migrations = []
+        else:
+            skipped_migrations = data["api"].get("skippedMigrations", [])
+
+    if "DISABLE_ALL" in skipped_migrations:
+        return
+
+    for migration in migrations:
+        if migration.get_migration_name() not in skipped_migrations:
+            try:
+                if migration.is_migration_needed():
+                    migration.migrate()
+            except Exception as e:
+                print(f"Error while migrating {migration.get_migration_name()}")
+                print(e)
+                print("Skipping this migration")

selfprivacy_api/migrations/fix_nixos_config_branch.py

@@ -0,0 +1,60 @@
+import os
+import subprocess
+
+from selfprivacy_api.migrations.migration import Migration
+
+
+class FixNixosConfigBranch(Migration):
+    def get_migration_name(self):
+        return "fix_nixos_config_branch"
+
+    def get_migration_description(self):
+        return """Mobile SelfPrivacy app introduced a bug in version 0.4.0.
+        New servers were initialized with a rolling-testing nixos config branch.
+        This was fixed in app version 0.4.2, but existing servers were not updated.
+        This migration fixes this by changing the nixos config branch to master.
+        """
+
+    def is_migration_needed(self):
+        """Check the current branch of /etc/nixos and return True if it is rolling-testing"""
+        current_working_directory = os.getcwd()
+        try:
+            os.chdir("/etc/nixos")
+            nixos_config_branch = subprocess.check_output(
+                ["git", "rev-parse", "--abbrev-ref", "HEAD"], start_new_session=True
+            )
+            os.chdir(current_working_directory)
+            if nixos_config_branch.decode("utf-8").strip() == "rolling-testing":
+                return True
+            else:
+                return False
+        except subprocess.CalledProcessError:
+            os.chdir(current_working_directory)
+            return False
+
+    def migrate(self):
+        """Affected server pulled the config with the --single-branch flag.
+        Git config remote.origin.fetch has to be changed, so all branches will be fetched.
+        Then, fetch all branches, pull and switch to master branch.
+        """
+        print("Fixing Nixos config branch")
+        current_working_directory = os.getcwd()
+        try:
+            os.chdir("/etc/nixos")
+
+            subprocess.check_output(
+                [
+                    "git",
+                    "config",
+                    "remote.origin.fetch",
+                    "+refs/heads/*:refs/remotes/origin/*",
+                ]
+            )
+            subprocess.check_output(["git", "fetch", "--all"])
+            subprocess.check_output(["git", "pull"])
+            subprocess.check_output(["git", "checkout", "master"])
+            os.chdir(current_working_directory)
+            print("Done")
+        except subprocess.CalledProcessError:
+            os.chdir(current_working_directory)
+            print("Error")

selfprivacy_api/migrations/migration.py

@@ -0,0 +1,28 @@
+from abc import ABC, abstractmethod
+
+"""
+Abstract Migration class
+This class is used to define the structure of a migration
+Migration has a function is_migration_needed() that returns True or False
+Migration has a function migrate() that does the migration
+Migration has a function get_migration_name() that returns the migration name
+Migration has a function get_migration_description() that returns the migration description
+"""
+
+
+class Migration(ABC):
+    @abstractmethod
+    def get_migration_name(self):
+        pass
+
+    @abstractmethod
+    def get_migration_description(self):
+        pass
+
+    @abstractmethod
+    def is_migration_needed(self):
+        pass
+
+    @abstractmethod
+    def migrate(self):
+        pass

selfprivacy_api/resources/common.py

@@ -24,4 +24,4 @@ class ApiVersion(Resource):
             401:
                 description: Unauthorized
         """
-        return {"version": "1.1.0"}
+        return {"version": "1.1.1"}