Do not assume that a node is the entire file

A roam node is no longer necessarily an entire file. It can be a file,
or any heading with an id.

Fixes #106

Author: egh

components/Sidebar/Link.tsx

@@ -152,7 +152,7 @@ export const PreviewLink = (props: LinkProps) => {
   const extraNoteStyle = outline ? outlineNoteStyle : viewerNoteStyle
   console.log(previewNode)
   const getText = () => {
-    fetch(`http://localhost:35901/file/${file}`)
+    fetch(`http://localhost:35901/node/${id}`)
       .then((res) => {
         return res.text()
       })

org-roam-ui.el

@@ -276,32 +276,33 @@ TODO: Be able to delete individual nodes."
   (org-roam-ui-follow-mode -1)
   (message "Connection with org-roam-ui closed."))
 
-(defun org-roam-ui--send-text (id ws)
-  "Send the text from org-node ID through the websocket WS."
+(defun org-roam-ui--get-text (id)
+  "Retrieve the text from org-node ID."
   (let*
       ((node (org-roam-populate (org-roam-node-create
                                  :id id)))
-       (file (org-roam-node-file node))
-       (text))
+       (file (org-roam-node-file node)))
     (org-roam-with-temp-buffer
         file
-      (setq text
-            (buffer-substring-no-properties (buffer-end -1) (buffer-end 1)))
-      text)
+      (when (> (org-roam-node-level node) 0)
+        ;; Heading nodes have level 1 and greater.
+        (goto-char (org-roam-node-point node))
+        (org-narrow-to-element))
+      (buffer-substring-no-properties (buffer-end -1) (buffer-end 1)))))
+
+(defun org-roam-ui--send-text (id ws)
+  "Send the text from org-node ID through the websocket WS."
+  (let ((text (org-roam-ui--get-text id)))
     (websocket-send-text ws
                          (json-encode
                           `((type . "orgText")
                             (data . ,text))))))
 
-(defservlet* file/:file text/plain ()
-  "Servlet for accessing file contents of org-roam files.
-
-Just sends the complete content of org-roam files rather than the specific
-node, as it's much faster to do that on the UI side."
-  (insert-file-contents-literally (org-link-decode file))
+(defservlet* node/:id text/plain ()
+  "Servlet for accessing node content."
+  (insert (org-roam-ui--get-text (org-link-decode id)))
   (httpd-send-header t "text/plain" 200 :Access-Control-Allow-Origin "*"))
 
-
 (defservlet* img/:file text/plain ()
   "Servlet for accessing images found in org-roam files."
   (progn

util/uniorg.tsx

@@ -34,9 +34,9 @@ export const UniOrg = (props: UniOrgProps) => {
 
   const [previewText, setPreviewText] = useState('')
 
-  const file = encodeURIComponent(encodeURIComponent(previewNode.file))
+  const id = encodeURIComponent(encodeURIComponent(previewNode.id))
   useEffect(() => {
-    fetch(`http://localhost:35901/file/${file}`)
+    fetch(`http://localhost:35901/node/${id}`)
       .then((res) => {
         return res.text()
       })