move fetch logic and use from solid-logic

src/components/source-editor-card/SourceEditorCard.ts

@@ -10,7 +10,7 @@ import styles from './SourceEditorCard.styles.css'
 import { getStatusSection } from '../../StatusSection'
 import { compactable } from '../../compactableFormats'
 import { sourceContext, SourceContext } from '../../primitives/context'
-import { getResponseMetadata } from '../../resourceLoader'
+import { fetchMetadata } from '../source-provider/resourceLoading'
 
 @customElement('source-pane-source-editor-card')
 export default class SourceEditorCard extends WebComponent {
@@ -191,10 +191,11 @@ export default class SourceEditorCard extends WebComponent {
       this._originalContent = data
       /// @@ show edited: make save button disabled until edited again.
       try {
-        const response = await fetcher.webOperation('HEAD', saveSubject.uri) // , defaultFetchHeaders())
-        if (!happy(response, 'HEAD')) return
-        const metadata = getResponseMetadata(store, saveSubject as any, response)
-        sourceContext.updateMetadata(metadata)
+        const metadata = await fetchMetadata(store, saveSubject)
+        sourceContext.updateMetadata({
+          contentType: metadata.contentType,
+          eTag: metadata.eTag
+        })
         this._resetEditorState()
       } catch (err) {
         throw err

src/components/source-provider/SourceProvider.ts

@@ -9,9 +9,9 @@ import { WebComponent } from 'solid-ui'
 import { sourceContext, SourceContext } from '../../primitives/context'
 import { SourcePaneState, EditorMetadata } from '../../types'
 import type SourceEditorCard from '../source-editor-card/SourceEditorCard'
-import { fetchContentAndMetadata } from '../../resourceLoader'
 import { fileExplorerContext, type FileExplorerContext } from 'solid-ui'
 import styles from './SourceProvider.styles.css'
+import { fetchContentAndMetadata } from './resourceLoading'
 void import('../source-editor-card/SourceEditorCard').then(() => undefined)
 
 function createDefaultSourcePaneState(): SourcePaneState {
@@ -111,9 +111,16 @@ export default class SourceProvider extends WebComponent {
         throw new Error('The element is missing the required `subject` property.')
       }
 
-      const { content, metadata } = await fetchContentAndMetadata(this.context.session.store as any, this.subject)
+      const store = (this.fileExplorerContextValue.store ?? this.context?.session.store) as DataBrowserContext['session']['store']
+      const { content, metadata } = await fetchContentAndMetadata(store, this.subject)
+      if (!metadata.contentType) {
+        throw new Error('Error: No content-type available!')
+      }
       this.originalContent = content
-      this.updateEditorMetadata(metadata)
+      this.updateEditorMetadata({
+        contentType: metadata.contentType,
+        eTag: metadata.eTag
+      })
       this.dataLoaded = true
     } catch (error: any) {
       const { showError } = getStatusSection()

src/components/source-provider/resourceLoading.ts

@@ -0,0 +1,48 @@
+import type { LiveStore, NamedNode } from 'rdflib'
+
+type ResourceMetadata = {
+  contentType: string | undefined
+  eTag: string | undefined
+}
+
+function assertSuccessfulHttpResponse(response: Response, method: string) {
+  if (response.ok) return
+
+  const message = response.status === 412
+    ? 'Error: File changed by someone else'
+    : `HTTP error on ${method}! Status: ${response.status}`
+  throw new Error(message)
+}
+
+function readContentType(response: Response) {
+  const contentTypeHeader = response.headers?.get('content-type')
+  return contentTypeHeader?.split(';')[0] ?? undefined
+}
+
+export async function fetchContentAndMetadata(store: LiveStore, subject: NamedNode): Promise<{ content: string, metadata: ResourceMetadata }> {
+  const response = await store.fetcher.webOperation('GET', subject.uri)
+  assertSuccessfulHttpResponse(response, 'GET')
+
+  const content = (response as Response & { responseText?: string }).responseText
+  if (content === undefined) {
+    throw new Error('No text in response object!!')
+  }
+
+  return {
+    content,
+    metadata: {
+      contentType: readContentType(response),
+      eTag: response.headers?.get('etag') ?? undefined
+    }
+  }
+}
+
+export async function fetchMetadata(store: LiveStore, subject: NamedNode): Promise<ResourceMetadata> {
+  const response = await store.fetcher.webOperation('HEAD', subject.uri)
+  assertSuccessfulHttpResponse(response, 'HEAD')
+
+  return {
+    contentType: readContentType(response),
+    eTag: response.headers?.get('etag') ?? undefined
+  }
+}