4.3.3 URL callback

The functions in the hook ‘wwe-url-callback-functions’ take care of the received page instead of rendering HTML with ‘wwe-render’. The default functions set for this hook are ‘wwe-doc-view’ and ‘wwe-content-type’.

Examples of functions for this hook:

• Show the main image of a page instead of loading the page itself

The functions should take the following arguments, note that the current buffer is the ‘url-retrieve’ process buffer:

• URL - The URL that was requested, a URL parsed by ‘wwe-parse-url’.
• CURRENT-URL - The URL of the page that was received, a parsed URL.
• BUFFER - The buffer, empty, prepared by ‘wwe-url-callback’, possibly a reused buffer. Remember to ‘kill-buffer’ BUFFER if you don’t end up using it.
• SAVE - Whether or not to save the page. If t or a file name/path, the page is to be saved without displaying; if 'wait, the page isn’t to be saved (no file prompt comes) until a hook in ‘wwe-url-callback-functions’ changes the value of SAVE
• PAGE - The file that was received (can be nil).
• RESPONSE - The response status code from the server (can be nil).
• CONTENT-TYPE - The content type of the file.
• CODING-SYSTEM - The coding system for the file (see also ‘wwe-determine-coding-system’).
• HEADERS - The HTTP headers sent by the server as set by ‘mail-header-extract’.
• REDIRECTED - If non-nil the URL was redirected.
• RETRIEVAL-ERROR - If non-nil an error that occurred during retrieval.

If a function takes care of things, it should return t - any function that doesn’t deal with the page should return nil, since the hooks are run with ‘run-hook-with-args-until-success’.