add cached media type detection

package.json

@@ -1,6 +1,6 @@
 {
   "name": "solid-logic",
-  "version": "6.0.1-4",
+  "version": "6.0.1-5",
   "description": "Core business logic of SolidOS",
   "main": "dist/index.cjs.js",
   "module": "dist/index.esm.js",

src/resource/resourceLogic.ts

@@ -1,4 +1,4 @@
-import { NamedNode, sym } from 'rdflib'
+import { NamedNode, sym, Util } from 'rdflib'
 import { ACL_LINK } from '../acl/aclLogic'
 import { ns } from '../util/ns'
 import { assertSuccessfulHttpResponse, isMissingError } from './resourceHttp'
@@ -55,6 +55,42 @@ export function createResourceLogic(store, aclLogic: AclLogic, containerLogic, t
     return pathEnd.startsWith('.') || pathEnd.endsWith('.acl') || pathEnd.endsWith('.meta') || pathEnd.endsWith('~')
   }
 
+  function isMediaType(resourceNode: NamedNode, mediaType: string) {
+    const typeURIs = store.findTypeURIs(resourceNode as any)
+    const normalizedMediaType = mediaType.toLowerCase()
+    const mediaTypePrefix = Util.mediaTypeClass(`${normalizedMediaType}/*`).uri.split('*')[0]
+
+    if (Object.keys(typeURIs).some(typeURI => typeURI.startsWith(mediaTypePrefix))) {
+      return true
+    }
+
+    const mediaTypeClasses: Record<string, string> = {
+      audio: 'http://purl.org/dc/dcmitype/Sound',
+      image: 'http://purl.org/dc/dcmitype/Image',
+      video: 'http://purl.org/dc/dcmitype/MovingImage'
+    }
+    if (mediaTypeClasses[normalizedMediaType] in typeURIs) {
+      return true
+    }
+
+    const contentTypes = store.fetcher.getHeader(resourceNode, 'content-type') || []
+    return contentTypes.some((contentType: string) =>
+      contentType.split(';', 1)[0].trim().toLowerCase().startsWith(`${normalizedMediaType}/`)
+    )
+  }
+
+  function isImage(resourceNode: NamedNode) {
+    return isMediaType(resourceNode, 'image')
+  }
+
+  function isAudio(resourceNode: NamedNode) {
+    return isMediaType(resourceNode, 'audio')
+  }
+
+  function isVideo(resourceNode: NamedNode) {
+    return isMediaType(resourceNode, 'video')
+  }
+
   function isWebId(resource: string | NamedNode) {
     const uri = typeof resource === 'string' ? resource : resource.value
 
@@ -259,6 +295,10 @@ export function createResourceLogic(store, aclLogic: AclLogic, containerLogic, t
     containerHasIndexDocument,
     isStorageRoot,
     isHiddenFile,
+    isMediaType,
+    isImage,
+    isAudio,
+    isVideo,
     isWebId
   }
 }

src/types.ts

@@ -173,6 +173,10 @@ export interface ResourceLogic {
     containerHasIndexDocument: (container: NamedNode) => boolean,
     isStorageRoot: (resource: NamedNode) => boolean,
     isHiddenFile: (resource: NamedNode) => boolean,
+    isMediaType: (resource: NamedNode, mediaType: string) => boolean,
+    isImage: (resource: NamedNode) => boolean,
+    isAudio: (resource: NamedNode) => boolean,
+    isVideo: (resource: NamedNode) => boolean,
     isWebId: (resource: string | NamedNode) => boolean
 }
 

test/resource/resourceLogic.test.ts

@@ -17,6 +17,7 @@ function buildResourceLogic(overrides: {
     fetcher: {
       webOperation: vi.fn(overrides.webOperation ?? (async () => { throw new Error('unexpected webOperation') })),
       _fetch: vi.fn(async (..._args: any[]) => ({ ok: true })),
+      getHeader: vi.fn().mockReturnValue([]),
       load: vi.fn(),
       unload: vi.fn()
     },
@@ -28,6 +29,7 @@ function buildResourceLogic(overrides: {
     any: vi.fn().mockReturnValue(undefined),
     holds: vi.fn().mockReturnValue(false),
     each: vi.fn().mockReturnValue([]),
+    findTypeURIs: vi.fn().mockReturnValue({}),
     removeMatches: vi.fn(),
     removeDocument: vi.fn(),
     sym
@@ -144,6 +146,35 @@ describe('createResourceLogic', () => {
     expect(resourceLogic.isHiddenFile(sym('https://example.com/workspace/file.ttl'))).toBe(false)
   })
 
+  it('recognizes media from RDF types and cached content-type headers without fetching', () => {
+    const { resourceLogic, store } = buildResourceLogic()
+    const image = sym('https://example.com/workspace/image.png')
+    const audio = sym('https://example.com/workspace/audio.mp3')
+    const video = sym('https://example.com/workspace/video.mp4')
+
+    store.fetcher.getHeader.mockImplementation((resource: any) => {
+      if (resource.uri === image.uri) return ['image/png; charset=binary']
+      if (resource.uri === audio.uri) return ['audio/mpeg']
+      return []
+    })
+
+    expect(resourceLogic.isImage(image)).toBe(true)
+    expect(resourceLogic.isAudio(audio)).toBe(true)
+    expect(resourceLogic.isVideo(video)).toBe(false)
+    expect(store.fetcher.webOperation).not.toHaveBeenCalled()
+  })
+
+  it('recognizes RDF media types when no content-type header is cached', () => {
+    const { resourceLogic, store } = buildResourceLogic()
+    const image = sym('https://example.com/workspace/image')
+    store.findTypeURIs.mockReturnValue({
+      'http://purl.org/dc/dcmitype/Image': true
+    })
+
+    expect(resourceLogic.isImage(image)).toBe(true)
+    expect(store.fetcher.webOperation).not.toHaveBeenCalled()
+  })
+
   it('builds index resources consistently for containers with or without a trailing slash', () => {
     const { resourceLogic } = buildResourceLogic()