As far as I understand, the gnome search, and maybe also the nautilus search, is driven or at least extended by tracker. I installed tracker in 18.04 to gather the content file search functionality I used in Ubuntu 17.10. I was able to add my folders in gnome-settings then, and they are indeed being scanned. But it only seems to use metadata like the name, not the files content:
~> tracker daemon -w Ressourcen-Aktualisierungen der Datenbank werden nun überwacht Alle Eigenschafte »nie:plainTextContent« werden ausgelassen Drücken Sie Strg+C zum Anhalten
The second line says that the Properties "nie:plainTextContent" is being skipped. I think what I want is to enable this, right? I tried to find a way, but I did only find outdated information when searching on the web and I could not find out myself how to enable this property.
The thing is, it seems to only skip nie:plainTextContent when indexing. A manual extraction gives the requested properties:
~> tracker extract ~/watched_folder/file.pdf @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . @prefix nie: <http://www.semanticdesktop.org/ontologies/2007/01/19/nie#> . @prefix nfo: <http://www.semanticdesktop.org/ontologies/2007/03/22/nfo#> . <file:///home/user/watched_folder/file.pdf> nfo:pageCount 51 ; nie:title "Lecture_File" ; a nfo:PaginatedTextDocument ; nie:plainTextContent "long text from the pdf" # this is what I want to search in!
Do you know how I can enable file content search for the Gnome Overview Search and/or the nautilus search? Is the nautilus search and the gnome shell search (typing in the "Activities" menu) both driven by tracker?