feat: add simple operation handlers

src/ldp/operations/SimpleDeleteOperationHandler.ts

@@ -0,0 +1,25 @@
+import { Operation } from './Operation';
+import { OperationHandler } from './OperationHandler';
+import { ResourceStore } from '../../storage/ResourceStore';
+import { ResponseDescription } from './ResponseDescription';
+import { UnsupportedHttpError } from '../../util/errors/UnsupportedHttpError';
+
+export class SimpleDeleteOperationHandler extends OperationHandler {
+  private readonly store: ResourceStore;
+
+  public constructor(store: ResourceStore) {
+    super();
+    this.store = store;
+  }
+
+  public async canHandle(input: Operation): Promise<void> {
+    if (input.method !== 'DELETE') {
+      throw new UnsupportedHttpError('This handler only supports DELETE operations.');
+    }
+  }
+
+  public async handle(input: Operation): Promise<ResponseDescription> {
+    await this.store.deleteResource(input.target);
+    return { identifier: input.target };
+  }
+}

src/ldp/operations/SimpleGetOperationHandler.ts

@@ -0,0 +1,25 @@
+import { Operation } from './Operation';
+import { OperationHandler } from './OperationHandler';
+import { ResourceStore } from '../../storage/ResourceStore';
+import { ResponseDescription } from './ResponseDescription';
+import { UnsupportedHttpError } from '../../util/errors/UnsupportedHttpError';
+
+export class SimpleGetOperationHandler extends OperationHandler {
+  private readonly store: ResourceStore;
+
+  public constructor(store: ResourceStore) {
+    super();
+    this.store = store;
+  }
+
+  public async canHandle(input: Operation): Promise<void> {
+    if (input.method !== 'GET') {
+      throw new UnsupportedHttpError('This handler only supports GET operations.');
+    }
+  }
+
+  public async handle(input: Operation): Promise<ResponseDescription> {
+    const body = await this.store.getRepresentation(input.target, input.preferences);
+    return { identifier: input.target, body };
+  }
+}

src/ldp/operations/SimplePostOperationHandler.ts

@@ -0,0 +1,28 @@
+import { Operation } from './Operation';
+import { OperationHandler } from './OperationHandler';
+import { ResourceStore } from '../../storage/ResourceStore';
+import { ResponseDescription } from './ResponseDescription';
+import { UnsupportedHttpError } from '../../util/errors/UnsupportedHttpError';
+
+export class SimplePostOperationHandler extends OperationHandler {
+  private readonly store: ResourceStore;
+
+  public constructor(store: ResourceStore) {
+    super();
+    this.store = store;
+  }
+
+  public async canHandle(input: Operation): Promise<void> {
+    if (input.method !== 'POST') {
+      throw new UnsupportedHttpError('This handler only supports POST operations.');
+    }
+    if (!input.body) {
+      throw new UnsupportedHttpError('POST operations require a body.');
+    }
+  }
+
+  public async handle(input: Operation): Promise<ResponseDescription> {
+    const identifier = await this.store.addResource(input.target, input.body);
+    return { identifier };
+  }
+}

test/unit/ldp/operations/SimpleDeleteOperationHandler.test.ts

@@ -0,0 +1,24 @@
+import { Operation } from '../../../../src/ldp/operations/Operation';
+import { ResourceStore } from '../../../../src/storage/ResourceStore';
+import { SimpleDeleteOperationHandler } from '../../../../src/ldp/operations/SimpleDeleteOperationHandler';
+import { UnsupportedHttpError } from '../../../../src/util/errors/UnsupportedHttpError';
+
+describe('A SimpleDeleteOperationHandler', (): void => {
+  const store = {} as unknown as ResourceStore;
+  const handler = new SimpleDeleteOperationHandler(store);
+  beforeEach(async(): Promise<void> => {
+    // eslint-disable-next-line @typescript-eslint/no-empty-function
+    store.deleteResource = jest.fn(async(): Promise<void> => {});
+  });
+
+  it('only supports GET operations.', async(): Promise<void> => {
+    await expect(handler.canHandle({ method: 'DELETE' } as Operation)).resolves.toBeUndefined();
+    await expect(handler.canHandle({ method: 'GET' } as Operation)).rejects.toThrow(UnsupportedHttpError);
+  });
+
+  it('deletes the resource from the store and returns its identifier.', async(): Promise<void> => {
+    await expect(handler.handle({ target: { path: 'url' }} as Operation)).resolves.toEqual({ identifier: { path: 'url' }});
+    expect(store.deleteResource).toHaveBeenCalledTimes(1);
+    expect(store.deleteResource).toHaveBeenLastCalledWith({ path: 'url' });
+  });
+});

test/unit/ldp/operations/SimpleGetOperationHandler.test.ts

@@ -0,0 +1,23 @@
+import { Operation } from '../../../../src/ldp/operations/Operation';
+import { Representation } from '../../../../src/ldp/representation/Representation';
+import { ResourceStore } from '../../../../src/storage/ResourceStore';
+import { SimpleGetOperationHandler } from '../../../../src/ldp/operations/SimpleGetOperationHandler';
+import { UnsupportedHttpError } from '../../../../src/util/errors/UnsupportedHttpError';
+
+describe('A SimpleGetOperationHandler', (): void => {
+  const store = {
+    getRepresentation: async(): Promise<Representation> => ({ dataType: 'quad' } as Representation),
+  } as unknown as ResourceStore;
+  const handler = new SimpleGetOperationHandler(store);
+
+  it('only supports GET operations.', async(): Promise<void> => {
+    await expect(handler.canHandle({ method: 'GET' } as Operation)).resolves.toBeUndefined();
+    await expect(handler.canHandle({ method: 'POST' } as Operation)).rejects.toThrow(UnsupportedHttpError);
+  });
+
+  it('returns the representation from the store with the input identifier.', async(): Promise<void> => {
+    await expect(handler.handle({ target: { path: 'url' }} as Operation)).resolves.toEqual(
+      { identifier: { path: 'url' }, body: { dataType: 'quad' }},
+    );
+  });
+});

test/unit/ldp/operations/SimplePostOperationHandler.test.ts

@@ -0,0 +1,22 @@
+import { Operation } from '../../../../src/ldp/operations/Operation';
+import { ResourceIdentifier } from '../../../../src/ldp/representation/ResourceIdentifier';
+import { ResourceStore } from '../../../../src/storage/ResourceStore';
+import { SimplePostOperationHandler } from '../../../../src/ldp/operations/SimplePostOperationHandler';
+import { UnsupportedHttpError } from '../../../../src/util/errors/UnsupportedHttpError';
+
+describe('A SimplePostOperationHandler', (): void => {
+  const store = {
+    addResource: async(): Promise<ResourceIdentifier> => ({ path: 'newPath' } as ResourceIdentifier),
+  } as unknown as ResourceStore;
+  const handler = new SimplePostOperationHandler(store);
+
+  it('only supports POST operations with a body.', async(): Promise<void> => {
+    await expect(handler.canHandle({ method: 'POST', body: { dataType: 'test' }} as Operation)).resolves.toBeUndefined();
+    await expect(handler.canHandle({ method: 'GET', body: { dataType: 'test' }} as Operation)).rejects.toThrow(UnsupportedHttpError);
+    await expect(handler.canHandle({ method: 'POST' } as Operation)).rejects.toThrow(UnsupportedHttpError);
+  });
+
+  it('adds the given representation to the store and returns the new identifier.', async(): Promise<void> => {
+    await expect(handler.handle({ method: 'POST', body: { dataType: 'test' }} as Operation)).resolves.toEqual({ identifier: { path: 'newPath' }});
+  });
+});