feat: Add required ACP headers

test/integration/AcpServer.test.ts

@@ -118,4 +118,21 @@ describe.each(stores)('An LDP handler with ACP using %s', (name, { storeConfig,
     response = await fetch(baseUrl);
     expect(response.status).toBe(200);
   });
+
+  it('returns the required Link headers.', async(): Promise<void> => {
+    const baseAcr = joinUrl(baseUrl, '.acr');
+    const response = await fetch(baseAcr, { method: 'OPTIONS' });
+    const linkHeaders = response.headers.get('link');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/solid/acp#AccessControlResource>; rel="type"');
+
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/auth/acl#Read>; rel="http://www.w3.org/ns/solid/acp#grant"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/auth/acl#Append>; rel="http://www.w3.org/ns/solid/acp#grant"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/auth/acl#Write>; rel="http://www.w3.org/ns/solid/acp#grant"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/auth/acl#Control>; rel="http://www.w3.org/ns/solid/acp#grant"');
+
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/solid/acp#target>; rel="http://www.w3.org/ns/solid/acp#attribute"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/solid/acp#agent>; rel="http://www.w3.org/ns/solid/acp#attribute"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/solid/acp#client>; rel="http://www.w3.org/ns/solid/acp#attribute"');
+    expect(linkHeaders).toContain('<http://www.w3.org/ns/solid/acp#issuer>; rel="http://www.w3.org/ns/solid/acp#attribute"');
+  });
 });

test/integration/config/ldp-with-acp.json

@@ -4,20 +4,24 @@
     "css:config/app/main/default.json",
     "css:config/app/init/default.json",
     "css:config/app/setup/disabled.json",
+
     "css:config/http/handler/simple.json",
     "css:config/http/middleware/no-websockets.json",
     "css:config/http/server-factory/no-websockets.json",
     "css:config/http/static/default.json",
     "css:config/identity/access/public.json",
+
     "css:config/identity/handler/default.json",
     "css:config/identity/ownership/token.json",
     "css:config/identity/pod/static.json",
+
     "css:config/ldp/authentication/debug-auth-header.json",
     "css:config/ldp/authorization/acp.json",
     "css:config/ldp/handler/default.json",
     "css:config/ldp/metadata-parser/default.json",
     "css:config/ldp/metadata-writer/default.json",
     "css:config/ldp/modes/default.json",
+
     "css:config/storage/key-value/memory.json",
     "css:config/storage/middleware/default.json",
     "css:config/util/auxiliary/acr.json",
@@ -30,7 +34,7 @@
   ],
   "@graph": [
     {
-      "comment": "An HTTP server with only the LDP handler as HttpHandler and an unsecure authenticator.",
+      "comment": "An HTTP server with only the LDP handler as HttpHandler and an unsecure authenticator using ACP.",
       "@id": "urn:solid-server:test:Instances",
       "@type": "RecordObject",
       "record": [

test/unit/server/middleware/AcpHeaderHandler.test.ts

@@ -0,0 +1,47 @@
+import { ACP } from '@solid/access-control-policy/dist/constant/acp';
+import { createResponse } from 'node-mocks-http';
+import type { AuxiliaryIdentifierStrategy } from '../../../../src/http/auxiliary/AuxiliaryIdentifierStrategy';
+import type { TargetExtractor } from '../../../../src/http/input/identifier/TargetExtractor';
+import type { HttpRequest } from '../../../../src/server/HttpRequest';
+import type { HttpResponse } from '../../../../src/server/HttpResponse';
+import { AcpHeaderHandler } from '../../../../src/server/middleware/AcpHeaderHandler';
+import { ACL } from '../../../../src/util/Vocabularies';
+import { SimpleSuffixStrategy } from '../../../util/SimpleSuffixStrategy';
+
+describe('an AcpHeaderHandler', (): void => {
+  const request: HttpRequest = {} as any;
+  let response: HttpResponse;
+  const modes = [ ACL.Read, ACL.Write ];
+  const attributes = [ ACP.agent, ACP.client ];
+  let targetExtractor: jest.Mocked<TargetExtractor>;
+  let strategy: AuxiliaryIdentifierStrategy;
+  let handler: AcpHeaderHandler;
+
+  beforeEach(async(): Promise<void> => {
+    response = createResponse() as HttpResponse;
+    targetExtractor = {
+      handleSafe: jest.fn().mockResolvedValue({ path: 'http://example.org/foo/bar' }),
+    } as any;
+
+    strategy = new SimpleSuffixStrategy('.acr');
+
+    handler = new AcpHeaderHandler(targetExtractor, strategy, modes, attributes);
+  });
+
+  it('adds no headers if the target is not an ACR.', async(): Promise<void> => {
+    await expect(handler.handle({ request, response })).resolves.toBeUndefined();
+    expect(response.getHeaders()).toEqual({});
+  });
+
+  it('adds all the required headers.', async(): Promise<void> => {
+    targetExtractor.handleSafe.mockResolvedValueOnce({ path: 'http://example.org/foo/bar.acr' });
+    await expect(handler.handle({ request, response })).resolves.toBeUndefined();
+    expect(response.getHeaders()).toEqual({ link: [
+      '<http://www.w3.org/ns/solid/acp#AccessControlResource>; rel="type"',
+      '<http://www.w3.org/ns/auth/acl#Read>; rel="http://www.w3.org/ns/solid/acp#grant"',
+      '<http://www.w3.org/ns/auth/acl#Write>; rel="http://www.w3.org/ns/solid/acp#grant"',
+      '<http://www.w3.org/ns/solid/acp#agent>; rel="http://www.w3.org/ns/solid/acp#attribute"',
+      '<http://www.w3.org/ns/solid/acp#client>; rel="http://www.w3.org/ns/solid/acp#attribute"',
+    ]});
+  });
+});