On Thu, Oct 12, 2017 at 12:07 AM Allen Li <vianchielfaura@gmail.com> wrote:

> %:url and $:title are wrong, they should be %:link and %:description
> respectively.
>
> Check out the source code of org-protocol-do-capture.
>
> The valid placeholders are
>
> type
> link
> description
> annotation
>

I don't use org-protocol, but I'd just like to understand how you derived
that.

Source code:

(defun org-protocol-do-capture (info)
  "Perform the actual capture based on INFO."
  (let* ((temp-parts (org-protocol-parse-parameters info))
(parts
  (cond
   ((and (listp info) (symbolp (car info))) info)
   ((= (length (car temp-parts)) 1) ;; First parameter is exactly one
character long
    (org-protocol-assign-parameters temp-parts '(:template :url :title
:body)))
   (t
    (org-protocol-assign-parameters temp-parts '(:url :title :body)))))
(template (or (plist-get parts :template)
       org-protocol-default-template-key))
(url (and (plist-get parts :url) (org-protocol-sanitize-uri (plist-get
parts :url))))
(type (and url (if (string-match "^\\([a-z]+\\):" url)
    (match-string 1 url))))
(title (or (plist-get parts :title) ""))
(region (or (plist-get parts :body) ""))
(orglink (if url
      (org-make-link-string
       url (if (string-match "[^[:space:]]" title) title url))
    title))
(org-capture-link-is-already-stored t)) ;; avoid call to org-store-link
    (setq org-stored-links
  (cons (list url title) org-stored-links))
    (org-store-link-props :type type
  :link url
  :description title
  :annotation orglink
  :initial region
  :query parts)
    (raise-frame)
    (funcall 'org-capture nil template)))

From that, we have:

(org-store-link-props :type type
  :link url
  :description title
  :annotation orglink
  :initial region
  :query parts)

but that is an internal call.. :link key gets its value from let-bound url
and :description gets its value from let-bound title.

And further up, url gets assigned value from a plist with key :url:

 (url (and (plist-get parts :url) (org-protocol-sanitize-uri (plist-get
parts :url))))

and title gets assigned value from a plist with key :title.

So that seems to match the documented: "The template refers to the data
through %:url and %:title placeholders.".

So I am surprised why %:link and %:description worked..

I didn't dig deeper as to where the connection with org-protocol and
org-capture happens.
-- 

Kaushal Modi