refactor: Restructure source code folder

This way the location of certain classes should make more sense

src/authorization/permissions/MethodModesExtractor.ts

@@ -0,0 +1,37 @@
+import type { Operation } from '../../http/Operation';
+import { NotImplementedHttpError } from '../../util/errors/NotImplementedHttpError';
+import { ModesExtractor } from './ModesExtractor';
+import { AccessMode } from './Permissions';
+
+const READ_METHODS = new Set([ 'GET', 'HEAD' ]);
+const WRITE_METHODS = new Set([ 'PUT', 'DELETE' ]);
+const APPEND_METHODS = new Set([ 'POST' ]);
+const SUPPORTED_METHODS = new Set([ ...READ_METHODS, ...WRITE_METHODS, ...APPEND_METHODS ]);
+
+/**
+ * Generates permissions for the base set of methods that always require the same permissions.
+ * Specifically: GET, HEAD, POST, PUT and DELETE.
+ */
+export class MethodModesExtractor extends ModesExtractor {
+  public async canHandle({ method }: Operation): Promise<void> {
+    if (!SUPPORTED_METHODS.has(method)) {
+      throw new NotImplementedHttpError(`Cannot determine permissions of ${method}`);
+    }
+  }
+
+  public async handle({ method }: Operation): Promise<Set<AccessMode>> {
+    const result = new Set<AccessMode>();
+    if (READ_METHODS.has(method)) {
+      result.add(AccessMode.read);
+    }
+    if (WRITE_METHODS.has(method)) {
+      result.add(AccessMode.write);
+      result.add(AccessMode.append);
+      result.add(AccessMode.create);
+      result.add(AccessMode.delete);
+    } else if (APPEND_METHODS.has(method)) {
+      result.add(AccessMode.append);
+    }
+    return result;
+  }
+}