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)
author: Eshel Yaron 2023-06-17 13:48:51 +0300
committer: Eli Zaretskii 2023-06-24 14:52:23 +0300
commit: dfba4347c71d70b8357979ff0fb4bb070b0ed60c (patch)
tree: 7e7dd66cbe9751ce766de5e0272570527adc13a4
parent: 8e8667246a4c06c8362515cbd6bead889babb748 (diff)
download: emacs-dfba4347c71d70b8357979ff0fb4bb070b0ed60c.tar.gz
emacs-dfba4347c71d70b8357979ff0fb4bb070b0ed60c.zip
3 files changed, 101 insertions, 0 deletions
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{<head>} section of @acronym{HTML} pages as
+@samp{<link>} 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
author	Eshel Yaron	2023-06-17 13:48:51 +0300
committer	Eli Zaretskii	2023-06-24 14:52:23 +0300
commit	dfba4347c71d70b8357979ff0fb4bb070b0ed60c (patch)
tree	7e7dd66cbe9751ce766de5e0272570527adc13a4
parent	8e8667246a4c06c8362515cbd6bead889babb748 (diff)
download	emacs-dfba4347c71d70b8357979ff0fb4bb070b0ed60c.tar.gz emacs-dfba4347c71d70b8357979ff0fb4bb070b0ed60c.zip

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}).
115	@kbd{w} calls @code{eww-copy-page-url}, which will copy the current	115	@kbd{w} calls @code{eww-copy-page-url}, which will copy the current
116	page's URL to the kill ring instead.	116	page's URL to the kill ring instead.
117		117
		118	@findex eww-copy-alternate-url
		119	@kindex A
		120	The @kbd{A} command (@code{eww-copy-alternate-url}) copies the URL
		121	of an alternate link of the current page into the kill ring. If the
		122	page specifies multiple alternate links, this command prompts for one
		123	of them in the minibuffer, with completion. Alternate links are
		124	references that an @acronym{HTML} page may include to point to other
		125	documents that act as its alternative representations. Notably,
		126	@acronym{HTML} pages can use alternate links to point to their
		127	translated versions and to @acronym{RSS} feeds. Alternate links
		128	appear in the @samp{<head>} section of @acronym{HTML} pages as
		129	@samp{<link>} elements with @samp{rel} attribute equal to
		130	@samp{``alternate''}, they are part of the page's metadata and are not
		131	visible in its rendered content.
		132
118	@findex eww-open-in-new-buffer	133	@findex eww-open-in-new-buffer
119	@kindex M-RET	134	@kindex M-RET
120	The @kbd{M-@key{RET}} command (@code{eww-open-in-new-buffer}) opens the	135	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
266	completions from 'eww-suggest-uris'. 'eww-suggest-uris' now includes	266	completions from 'eww-suggest-uris'. 'eww-suggest-uris' now includes
267	bookmark URIs.	267	bookmark URIs.
268		268
		269	+++
		270	*** New command 'eww-copy-alternate-url'.
		271	It copies an alternate link to the page currently visited in EWW into
		272	the kill ring. Alternate links are optional metadata that HTML pages
		273	use for linking to their alternative representations, such as
		274	translated versions or associated RSS feeds.
		275
269	** go-ts-mode	276	** go-ts-mode
270		277
271	+++	278	+++


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."
1086	"&" #'eww-browse-with-external-browser	1086	"&" #'eww-browse-with-external-browser
1087	"d" #'eww-download	1087	"d" #'eww-download
1088	"w" #'eww-copy-page-url	1088	"w" #'eww-copy-page-url
		1089	"A" #'eww-copy-alternate-url
1089	"C" #'url-cookie-list	1090	"C" #'url-cookie-list
1090	"v" #'eww-view-source	1091	"v" #'eww-view-source
1091	"R" #'eww-readable	1092	"R" #'eww-readable
@@ -2576,4 +2577,82 @@ Otherwise, the restored buffer will contain a prompt to do so by using
2576		2577
2577	(provide 'eww)	2578	(provide 'eww)
2578		2579
		2580	;;; Alternate links (RSS and Atom feeds, etc.)
		2581
		2582	(defun eww--alternate-urls (dom &optional base)
		2583	"Return an alist of alternate links in DOM.
		2584
		2585	Each element is a list of the form (URL TYPE TITLE) where URL is
		2586	the href attribute of the link expanded relative to BASE, TYPE is
		2587	its type attribute, and TITLE is its title attribute. If any of
		2588	these attributes is absent, the corresponding element is nil."
		2589	(let ((alternates
		2590	(seq-filter
		2591	(lambda (attrs) (string= (alist-get 'rel attrs)
		2592	"alternate"))
		2593	(mapcar #'dom-attributes (dom-by-tag dom 'link)))))
		2594	(mapcar (lambda (alternate)
		2595	(list (url-expand-file-name (alist-get 'href alternate)
		2596	base)
		2597	(alist-get 'type alternate)
		2598	(alist-get 'title alternate)))
		2599	alternates)))
		2600
		2601	(defun eww-read-alternate-url ()
		2602	"Get the URL of an alternate link of this page.
		2603
		2604	If there is just one alternate link, return its URL. If there
		2605	are multiple alternate links, prompt for one in the minibuffer
		2606	with completion. If there are none, return nil."
		2607	(when-let ((alternates (eww--alternate-urls
		2608	(plist-get eww-data :dom)
		2609	(plist-get eww-data :url))))
		2610	(let ((url-max-width
		2611	(seq-max (mapcar #'string-pixel-width
		2612	(mapcar #'car alternates))))
		2613	(title-max-width
		2614	(seq-max (mapcar #'string-pixel-width
		2615	(mapcar #'caddr alternates))))
		2616	(sep-width (string-pixel-width " ")))
		2617	(if (cdr alternates)
		2618	(let ((completion-extra-properties
		2619	(list :annotation-function
		2620	(lambda (feed)
		2621	(let* ((attrs (alist-get feed
		2622	alternates
		2623	nil
		2624	nil
		2625	#'string=))
		2626	(type (car attrs))
		2627	(title (cadr attrs)))
		2628	(concat
		2629	(propertize " " 'display
		2630	`(space :align-to
		2631	(,(+ sep-width
		2632	url-max-width))))
		2633	title
		2634	(when type
		2635	(concat
		2636	(propertize " " 'display
		2637	`(space :align-to
		2638	(,(+ (* 2 sep-width)
		2639	url-max-width
		2640	title-max-width))))
		2641	"[" type "]"))))))))
		2642	(completing-read "Alternate URL: " alternates nil t))
		2643	(caar alternates)))))
		2644
		2645	(defun eww-copy-alternate-url ()
		2646	"Copy an alternate URL of the current page into the kill ring.
		2647
		2648	Alternate links are references that an HTML page may include to
		2649	point to its alternative representations, such as a translated
		2650	version or an RSS feed."
		2651	(interactive nil eww-mode)
		2652	(if-let ((url (eww-read-alternate-url)))
		2653	(progn
		2654	(kill-new url)
		2655	(message "Copied %s to kill ring" url))
		2656	(user-error "No alternate links found on this page!")))
		2657
2579	;;; eww.el ends here	2658	;;; eww.el ends here