feat: Full rework of account management

Complete rewrite of the account management and related systems.
Makes the architecture more modular,
allowing for easier extensions and configurations.

test/unit/identity/interaction/ViewInteractionHandler.test.ts

@@ -0,0 +1,56 @@
+import { RepresentationMetadata } from '../../../../src/http/representation/RepresentationMetadata';
+import type { JsonInteractionHandlerInput,
+  JsonInteractionHandler } from '../../../../src/identity/interaction/JsonInteractionHandler';
+import type { JsonView } from '../../../../src/identity/interaction/JsonView';
+import { ViewInteractionHandler } from '../../../../src/identity/interaction/ViewInteractionHandler';
+import { MethodNotAllowedHttpError } from '../../../../src/util/errors/MethodNotAllowedHttpError';
+
+describe('A BaseInteractionHandler', (): void => {
+  let input: JsonInteractionHandlerInput;
+  let source: jest.Mocked<JsonInteractionHandler & JsonView>;
+  let handler: ViewInteractionHandler;
+
+  beforeEach(async(): Promise<void> => {
+    input = {
+      method: 'GET',
+      target: { path: 'target' },
+      json: { input: 'data' },
+      metadata: new RepresentationMetadata(),
+    };
+
+    source = {
+      getView: jest.fn().mockResolvedValue('view'),
+      canHandle: jest.fn(),
+      handle: jest.fn().mockResolvedValue('response'),
+      handleSafe: jest.fn(),
+    };
+
+    handler = new ViewInteractionHandler(source);
+  });
+
+  it('can only handle GET and POST requests.', async(): Promise<void> => {
+    input.method = 'DELETE';
+
+    await expect(handler.canHandle(input)).rejects.toThrow(MethodNotAllowedHttpError);
+
+    input.method = 'GET';
+    await expect(handler.canHandle(input)).resolves.toBeUndefined();
+
+    input.method = 'POST';
+    await expect(handler.canHandle(input)).resolves.toBeUndefined();
+  });
+
+  it('returns the view on GET requests.', async(): Promise<void> => {
+    input.method = 'GET';
+    await expect(handler.handle(input)).resolves.toBe('view');
+    expect(source.getView).toHaveBeenCalledTimes(1);
+    expect(source.getView).toHaveBeenLastCalledWith(input);
+  });
+
+  it('calls the handlePost function on POST requests.', async(): Promise<void> => {
+    input.method = 'POST';
+    await expect(handler.handle(input)).resolves.toBe('response');
+    expect(source.handle).toHaveBeenCalledTimes(1);
+    expect(source.handle).toHaveBeenLastCalledWith(input);
+  });
+});