From dfba4347c71d70b8357979ff0fb4bb070b0ed60c Mon Sep 17 00:00:00 2001 From: Eshel Yaron Date: Sat, 17 Jun 2023 13:48:51 +0300 Subject: [PATCH] New command 'eww-copy-alternate-url' This adds a new command to EWW that copies an alternate link to the currently visited page into the kill ring. This is useful for subscribing to website feeds, etc. * lisp/net/eww.el (eww--alternate-urls, eww-read-alternate-url): New functions. (eww-copy-alternate-url): New command. (eww-mode-map): Bind it to 'A'. * doc/misc/eww.texi (Basics): Document it. * etc/NEWS: Announce it. (Bug#64126) --- doc/misc/eww.texi | 15 +++++++++ etc/NEWS | 7 +++++ lisp/net/eww.el | 79 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 101 insertions(+) diff --git a/doc/misc/eww.texi b/doc/misc/eww.texi index c02e9db11c9..cff48bd601e 100644 --- a/doc/misc/eww.texi +++ b/doc/misc/eww.texi @@ -115,6 +115,21 @@ web page hit @kbd{g} (@code{eww-reload}). @kbd{w} calls @code{eww-copy-page-url}, which will copy the current page's URL to the kill ring instead. +@findex eww-copy-alternate-url +@kindex A + The @kbd{A} command (@code{eww-copy-alternate-url}) copies the URL +of an alternate link of the current page into the kill ring. If the +page specifies multiple alternate links, this command prompts for one +of them in the minibuffer, with completion. Alternate links are +references that an @acronym{HTML} page may include to point to other +documents that act as its alternative representations. Notably, +@acronym{HTML} pages can use alternate links to point to their +translated versions and to @acronym{RSS} feeds. Alternate links +appear in the @samp{} section of @acronym{HTML} pages as +@samp{} elements with @samp{rel} attribute equal to +@samp{``alternate''}, they are part of the page's metadata and are not +visible in its rendered content. + @findex eww-open-in-new-buffer @kindex M-RET The @kbd{M-@key{RET}} command (@code{eww-open-in-new-buffer}) opens the diff --git a/etc/NEWS b/etc/NEWS index 467ac3ee587..0f674c6465f 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -266,6 +266,13 @@ The interactive minibuffer prompt when invoking 'eww' now provides completions from 'eww-suggest-uris'. 'eww-suggest-uris' now includes bookmark URIs. ++++ +*** New command 'eww-copy-alternate-url'. +It copies an alternate link to the page currently visited in EWW into +the kill ring. Alternate links are optional metadata that HTML pages +use for linking to their alternative representations, such as +translated versions or associated RSS feeds. + ** go-ts-mode +++ diff --git a/lisp/net/eww.el b/lisp/net/eww.el index 61f0f47373d..89f7ba37cc1 100644 --- a/lisp/net/eww.el +++ b/lisp/net/eww.el @@ -1086,6 +1086,7 @@ the like." "&" #'eww-browse-with-external-browser "d" #'eww-download "w" #'eww-copy-page-url + "A" #'eww-copy-alternate-url "C" #'url-cookie-list "v" #'eww-view-source "R" #'eww-readable @@ -2576,4 +2577,82 @@ Otherwise, the restored buffer will contain a prompt to do so by using (provide 'eww) +;;; Alternate links (RSS and Atom feeds, etc.) + +(defun eww--alternate-urls (dom &optional base) + "Return an alist of alternate links in DOM. + +Each element is a list of the form (URL TYPE TITLE) where URL is +the href attribute of the link expanded relative to BASE, TYPE is +its type attribute, and TITLE is its title attribute. If any of +these attributes is absent, the corresponding element is nil." + (let ((alternates + (seq-filter + (lambda (attrs) (string= (alist-get 'rel attrs) + "alternate")) + (mapcar #'dom-attributes (dom-by-tag dom 'link))))) + (mapcar (lambda (alternate) + (list (url-expand-file-name (alist-get 'href alternate) + base) + (alist-get 'type alternate) + (alist-get 'title alternate))) + alternates))) + +(defun eww-read-alternate-url () + "Get the URL of an alternate link of this page. + +If there is just one alternate link, return its URL. If there +are multiple alternate links, prompt for one in the minibuffer +with completion. If there are none, return nil." + (when-let ((alternates (eww--alternate-urls + (plist-get eww-data :dom) + (plist-get eww-data :url)))) + (let ((url-max-width + (seq-max (mapcar #'string-pixel-width + (mapcar #'car alternates)))) + (title-max-width + (seq-max (mapcar #'string-pixel-width + (mapcar #'caddr alternates)))) + (sep-width (string-pixel-width " "))) + (if (cdr alternates) + (let ((completion-extra-properties + (list :annotation-function + (lambda (feed) + (let* ((attrs (alist-get feed + alternates + nil + nil + #'string=)) + (type (car attrs)) + (title (cadr attrs))) + (concat + (propertize " " 'display + `(space :align-to + (,(+ sep-width + url-max-width)))) + title + (when type + (concat + (propertize " " 'display + `(space :align-to + (,(+ (* 2 sep-width) + url-max-width + title-max-width)))) + "[" type "]")))))))) + (completing-read "Alternate URL: " alternates nil t)) + (caar alternates))))) + +(defun eww-copy-alternate-url () + "Copy an alternate URL of the current page into the kill ring. + +Alternate links are references that an HTML page may include to +point to its alternative representations, such as a translated +version or an RSS feed." + (interactive nil eww-mode) + (if-let ((url (eww-read-alternate-url))) + (progn + (kill-new url) + (message "Copied %s to kill ring" url)) + (user-error "No alternate links found on this page!"))) + ;;; eww.el ends here -- 2.39.2