share support for attachment file download

src/share/content_renderer.js

@@ -62,12 +62,29 @@ function renderText(result, note) {
         for (const linkEl of document.querySelectorAll("a")) {
             const href = linkEl.getAttribute("href");
 
-            if (href?.startsWith("#")) {
+            if (!href?.startsWith("#")) {
-                const notePathSegments = href.split("/");
+                continue;
+            }
 
+            const linkRegExp = /attachmentId=([a-zA-Z0-9_]+)/g;
+            let attachmentMatch
+            if (attachmentMatch = linkRegExp.exec(href)) {
+                const attachmentId = attachmentMatch[1];
+                const attachment = shaca.getAttachment(attachmentId);
+
+                if (attachment) {
+                    linkEl.setAttribute("href", `api/attachments/${attachmentId}/download`);
+                    linkEl.classList.add(`attachment-link`);
+                    linkEl.classList.add(`role-${attachment.role}`);
+                    linkEl.innerText = attachment.title;
+                } else {
+                    linkEl.removeAttribute("href");
+                }
+            } else {
+                const [notePath] = href.split('?');
+                const notePathSegments = notePath.split("/");
                 const noteId = notePathSegments[notePathSegments.length - 1];
                 const linkedNote = shaca.getNote(noteId);
-
                 if (linkedNote) {
                     linkEl.setAttribute("href", linkedNote.shareId);
                     linkEl.classList.add(`type-${linkedNote.type}`);

src/share/routes.js

@@ -8,6 +8,7 @@ const shareRoot = require("./share_root");
 const contentRenderer = require("./content_renderer");
 const assetPath = require("../services/asset_path");
 const appPath = require("../services/app_path");
+const utils = require("../services/utils.js");
 
 function getSharedSubTreeRoot(note) {
     if (note.noteId === shareRoot.SHARE_ROOT_NOTE_ID) {
@@ -253,6 +254,29 @@ function register(router) {
         }
     });
 
+    router.get('/share/api/attachments/:attachmentId/download', (req, res, next) => {
+        shacaLoader.ensureLoad();
+
+        let attachment;
+
+        if (!(attachment = checkAttachmentAccess(req.params.attachmentId, req, res))) {
+            return;
+        }
+
+        addNoIndexHeader(attachment.note, res);
+
+        const utils = require("../services/utils");
+
+        const filename = utils.formatDownloadTitle(attachment.title, null, attachment.mime);
+
+        res.setHeader('Content-Disposition', utils.getContentDisposition(filename));
+
+        res.setHeader("Cache-Control", "no-cache, no-store, must-revalidate");
+        res.setHeader('Content-Type', attachment.mime);
+
+        res.send(attachment.getContent());
+    });
+
     // used for PDF viewing
     router.get('/share/api/notes/:noteId/view', (req, res, next) => {
         shacaLoader.ensureLoad();