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Read Me

This library was created to fascilitate quickly building web pages, though it also includes tools for working with parsed xml

Code Generation with esxml.el

This library provides to formats for xml code generation. The primary form is esxml. esxml is the form that is returned by such functions as libxml-parse-xml-region and is used internally by emacs in many xml related libraries.

A brief example

The following is a very simple esxml document, paths are handled directly, via a case statement. While this is not good practice, this is meant to be a very simple example.

sxml example

(let ((count 0))
  (defun sxml-demo (httpcon)
    (incf count)
    (case (intern (elnode-http-pathinfo httpcon))
      (/messages (with-current-buffer "*Messages*"
                   (sxml-to-xml `(html (body (pre ,(buffer-string)))))))

      (t (sxml-to-xml
          `(html
            (body
             (h1 "Hello from Emacs!") (br)
             "Trying to visit " ,(format "%s" (elnode-http-pathinfo httpcon)) (br)
             "Visit " (a (@ (href "/messages")) "messages") " to see the *Messages* buffer." (br)
             "Have been visited " ,(format "%s" count) " times since last started.")))))))

This outputs the following HTML:

<html >
  <body >
    <h1 >Hello from Emacs!</h1><br />
    Trying to visit /anywhere<br />
    Visit <a href="/messages">messages</a> to see the *Messages* buffer.<br />
    Have been visited 1 times since last started.
  </body>
</html>

esxml example

(let ((count 0))
  (defun esxml-demo (httpcon)
    (incf count)
    (case (intern (elnode-http-pathinfo httpcon))
      (/messages (with-current-buffer "*Messages*"
                   (esxml-to-xml `(html () (body () (pre () ,(buffer-string)))))))
      
      (t (esxml-to-xml
          `(html ()
                 (body ()
                       (h1 () "Hello from Emacs!")
                       (br) "Trying to visit " ,(format "%s" (elnode-http-pathinfo httpcon))
                       (br)  "Visit " (a ((href . "/messages")) "messages")  " to see the *Messages* buffer."
                       (br) "Have been visited " ,(format "%s" count) " times since last started.")))))))

Advanced examples

A standard page generator

Extracting data from HTML and XML documents with esxml-query.el

(require 'dom)
(require 'esxml-query)

(url-retrieve
 "https://schneierfacts.com/"
 (lambda (status &rest args)
   (let* ((html (libxml-parse-html-region url-http-end-of-headers (point-max)))
          (fact (esxml-query "p.fact" html)))
     (message "Did you know: %s" (car (dom-children fact))))))
(require 'dom)
(require 'esxml-query)

(url-retrieve
 "https://www.xkcd.com/rss.xml"
 (lambda (status &rest args)
   (goto-char url-http-end-of-headers)
   (forward-line 1)
   (let* ((xml (libxml-parse-xml-region (point) (point-max)))
          (latest (esxml-query "rss>channel>item" xml))
          (title (car (dom-children (esxml-query "title" latest))))
          (link (car (dom-children (esxml-query "link" latest)))))
     (message "%S: %s" title link))))

See the following packages for more examples: