JavaScriptSolidServer · melvincarvalho · Apr 22, 2026 · Apr 22, 2026
@@ -239,6 +239,16 @@ export function getContentType(filePath) {
     '.m3u8': 'application/vnd.apple.mpegurl',
     '.pls': 'audio/x-scpls'
   };
+
+  // Solid convention dotfiles (.acl, .meta) are RDF resources. path.extname
+  // returns '' for leading-dot names, so the map lookup above misses them;
+  // fall back to a basename check and tag them as JSON-LD — the format JSS
+  // writes them in via serializeAcl() / createPodStructure(). Content
+  // negotiation then handles Turtle-native clients (umai, Soukai-based apps,
+  // older Solid tooling) via handleGet's conneg branch.
+  const base = path.basename(filePath);
+  if (base === '.acl' || base === '.meta') return 'application/ld+json';
+
   return types[ext] || 'application/octet-stream';
 }
 

@@ -194,6 +194,73 @@ describe('Content Negotiation (conneg enabled)', () => {
         'Accept-Post should include text/turtle');
     });
   });
+
+  // Regression coverage for #294 — Solid convention dotfiles (.acl, .meta)
+  // were excluded from conneg because getContentType() returned
+  // application/octet-stream for them. Turtle-native clients (umai etc.)
+  // fetching <container>/.meta got JSON-LD back and errored on parse.
+  describe('Solid convention dotfiles (#294)', () => {
+    const metaData = {
+      '@context': { 'ldp': 'http://www.w3.org/ns/ldp#' },
+      '@id': '',
+      '@type': 'ldp:BasicContainer'
+    };
+
+    before(async () => {
+      // Write a JSON-LD .meta file (the format JSS writes internally).
+      await request('/connegtest/public/.meta', {
+        method: 'PUT',
+        headers: { 'Content-Type': 'application/ld+json' },
+        body: JSON.stringify(metaData),
+        auth: 'connegtest'
+      });
+    });
+
+    it('serves .meta as JSON-LD by default', async () => {
+      const res = await request('/connegtest/public/.meta', { auth: 'connegtest' });
+      assertStatus(res, 200);
+      assertHeaderContains(res, 'Content-Type', 'application/ld+json');
+    });
+
+    it('serves .meta as Turtle when Accept: text/turtle (the umai case)', async () => {
+      const res = await request('/connegtest/public/.meta', {
+        headers: { 'Accept': 'text/turtle' },
+        auth: 'connegtest'
+      });
+      assertStatus(res, 200);
+      assertHeaderContains(res, 'Content-Type', 'text/turtle');
+      const turtle = await res.text();
+      // First byte after the `@prefix` block must parse as Turtle,
+      // not '{' (the bug signature umai hit).
+      assert.ok(!turtle.trimStart().startsWith('{'),
+        `response looks like JSON, not Turtle: ${turtle.slice(0, 60)}`);
+    });
+
+    it('accepts Turtle PUT to .meta and round-trips to JSON-LD', async () => {
+      const turtle = `
+        @prefix ldp: <http://www.w3.org/ns/ldp#>.
+        <> a ldp:BasicContainer.
+      `;
+      const putRes = await request('/connegtest/public/.meta', {
+        method: 'PUT',
+        headers: { 'Content-Type': 'text/turtle' },
+        body: turtle,
+        auth: 'connegtest'
+      });
+      assert.ok(putRes.status < 300, `PUT turtle should succeed, got ${putRes.status}`);
+
+      // Default GET now serves the converted-and-stored JSON-LD.
+      const getRes = await request('/connegtest/public/.meta', {
+        headers: { 'Accept': 'application/ld+json' },
+        auth: 'connegtest'
+      });
+      assertStatus(getRes, 200);
+      assertHeaderContains(getRes, 'Content-Type', 'application/ld+json');
+      const body = await getRes.json();
+      assert.ok(body['@context'] || body['@graph'] || body['@type'] || body['@id'],
+        'round-tripped JSON-LD should have at least one @-keyword');
+    });
+  });
 });
 
 describe('Content Negotiation (conneg disabled - default)', () => {

@@ -7,7 +7,7 @@
 
 import { describe, it } from 'node:test';
 import assert from 'node:assert';
-import { getPodName } from '../src/utils/url.js';
+import { getPodName, getContentType } from '../src/utils/url.js';
 
 describe('getPodName', () => {
   describe('subdomain mode', () => {
@@ -73,3 +73,37 @@ describe('getPodName', () => {
     });
   });
 });
+
+// Regression coverage for #294 — .acl and .meta must be recognised as RDF
+// resources so content negotiation kicks in for Turtle-native clients.
+describe('getContentType', () => {
+  describe('extension-based mapping (existing)', () => {
+    it('maps .jsonld → application/ld+json', () => {
+      assert.strictEqual(getContentType('/x/card.jsonld'), 'application/ld+json');
+    });
+    it('maps .ttl → text/turtle', () => {
+      assert.strictEqual(getContentType('/x/card.ttl'), 'text/turtle');
+    });
+    it('falls back to application/octet-stream for unknown extensions', () => {
+      assert.strictEqual(getContentType('/x/file.xyz'), 'application/octet-stream');
+    });
+  });
+
+  describe('Solid convention dotfiles (#294)', () => {
+    it('treats .acl as application/ld+json (the format JSS writes it in)', () => {
+      assert.strictEqual(getContentType('/alice/public/.acl'), 'application/ld+json');
+      assert.strictEqual(getContentType('.acl'), 'application/ld+json');
+    });
+
+    it('treats .meta as application/ld+json', () => {
+      assert.strictEqual(getContentType('/alice/public/.meta'), 'application/ld+json');
+      assert.strictEqual(getContentType('.meta'), 'application/ld+json');
+    });
+
+    it('does not mistake non-dotfile paths containing .acl for ACL files', () => {
+      // A regular file that happens to have "acl" in its name/path stays
+      // classified by extension, not by coincidence.
+      assert.strictEqual(getContentType('/alice/notes/my-acl-plan.md'), 'text/markdown');
+    });
+  });
+});