Content server: Allow disabling full text search via the web interface. Fixes #2020237 [[content server] Disable fulltext search activation via web interface](https://bugs.launchpad.net/calibre/+bug/2020237)

src/calibre/srv/fts.py

@@ -54,6 +54,14 @@ def fts_search(ctx, rd):
     return ans
 
 
+@endpoint('/fts/disable', needs_db_write=True)
+def fts_disable(ctx, rd):
+    db = get_library_data(ctx, rd)[0]
+    if db.is_fts_enabled():
+        db.enable_fts(enabled=False)
+    return ''
+
+
 @endpoint('/fts/reindex', needs_db_write=True, methods=('POST',))
 def fts_reindex(ctx, rd):
     db = get_library_data(ctx, rd)[0]

src/pyj/book_list/fts.pyj

@@ -8,7 +8,7 @@ from ajax import ajax, ajax_send
 from book_list.cover_grid import THUMBNAIL_MAX_HEIGHT, THUMBNAIL_MAX_WIDTH
 from book_list.globals import get_current_query, get_session_data
 from book_list.library_data import current_library_id, download_url
-from book_list.router import back, open_book_url, push_state
+from book_list.router import back, home, open_book_url, push_state
 from book_list.top_bar import create_top_bar
 from book_list.ui import set_panel_handler
 from book_list.views import create_image
@@ -34,7 +34,9 @@ add_extra_css(def():
 )
 
 def component(name):
-    return document.getElementById(overall_container_id)?.querySelector(f'[data-component="{name}"]')
+    c = document.getElementById(overall_container_id)
+    if c:
+        return c.querySelector(f'[data-component="{name}"]')
 
 
 def showing_search_panel():
@@ -157,6 +159,8 @@ def clear_to_help():
     container.appendChild(E.div(
         style='margin-top: 1ex',
         E.a(_('Re-index all books in this library'), class_='blue-link', href='javascript:void(0)', onclick=reindex_all),
+        E.span('\xa0\xa0'),
+        E.a(_('Disable full text search'), class_='blue-link', href='javascript:void(0)', onclick=disable_fts),
     ))
     container = container.firstChild
     fts_url = 'https://www.sqlite.org/fts5.html#full_text_query_syntax'
@@ -245,6 +249,32 @@ def reindex_all():
     )
 
 
+def disable_fts_backend():
+    def on_response(end_type, xhr, ev):
+        if end_type is 'abort' or not showing_search_panel():
+            return
+        if end_type is not 'load':
+            if xhr.status is 403:
+                return error_dialog(_('Permission denied'), _(
+                    'You do not have permission to disable FTS. Only logged in users with write permission are allowed to disable FTS.'), xhr.error_html)
+            return error_dialog(_('Disabling FTS failed'), _('Disabling FTS failed. Click "Show details" for more information.'), xhr.error_html)
+        info_dialog(_('Full text searching disabled'), _('Full text searching for this library has been disabled. In the future the entire library will have to be re-indexed when re-enabling full text searching.'), on_close=def():
+            window.setTimeout(home)
+        )
+
+    ajax(f'fts/disable', on_response, bypass_cache=True).send()
+
+
+
+def disable_fts():
+    question_dialog(_('Are you sure?'), _('Disabling full text search means that in the future the entire library will have to be re-indexed to use full text search. Are you sure you want to proceed?'),
+        def (yes):
+            if yes:
+                disable_fts_backend()
+    )
+
+
+
 def book_result_tile_clicked(ev):
     result_tile = ev.currentTarget
     bid = int(result_tile.dataset.bookId)