Script Library: 1213 scripts
 

never-cache.r

rebol [ Title: "never cache" File: %never-cache.r Date: 22-Nov-2002 Version: 1.0.2 Needs: [] Author: "Anton Rolls" Language: 'English Purpose: {function that outputs rebol and javascript code to ensure a page is always freshly loaded from the server} Library: [ level: 'advanced platform: 'all type: 'function domain: [html web cgi] tested-under: "at least Rebol/View1.2.8 on WinXP, IE6.0" support: none license: 'mit see-also: none ] Usage: { make sure never-cache.r is run before using the never-cache function. Our system uses Brian Hawley's require function, so I recommend the following require line in the server.r script: require %public/lib/never-cache.r then just include the line: print never-cache somewhere in your rebol cgi's (preferably near the top, before images etc.)} ToDo: { - } History: [ 1.0.0 [10-Oct-2002 {First version} "Anton"] 1.0.1 [27-Oct-2002 {now simply returns a string of code, no longer print's it for you, this allows it to be used with current implementation of embedded rebol scripting} "Anton"] 1.0.2 [22-Nov-2002 {increased default delay time to 1500} "Anton"] ] Notes: { This function assumes that it will be used in a rebol server-side cgi script, and that javascript is enabled in the client browser. I saw this as another way to force a reload from the server location.reload(force); } ] never-cache: func [{print some code such that the page it appears will always be loaded fresh from the server} /delay ms "minimum time in milliseconds after which the page will be forced to reload (default: 1000 ms = 1 second)" /debug "write the contents of some variables into the document" /local days seconds-per-day time seconds milliseconds ][ if not delay [ms: 1500] ; set default value ; calculate time in milliseconds, in same format as javascript's Date.getTime() days: (now - 1-jan-1970) ; this doesn't account for timezone (now/zone) - see below seconds-per-day: 24.0 * 3600 time: now/time/precise seconds: (days * seconds-per-day) + ((time/hour * 3600) + (time/minute * 60) + time/second) seconds: seconds - to-integer now/zone ; account for timezone milliseconds: seconds * 1000.0 rejoin [ {<script language="JavaScript"><!--^/} {^-var timestamp = } milliseconds {;^/} either debug [{^-document.write(timestamp + " (timestamp)<br>");^/}][""] {^-var now = (new Date()).getTime();^/} either debug [{^-document.write(now + " (now)<br>");^/}][""] { if (now - timestamp > } ms ") { // more than " (ms / 1000) { second(s) old? //alert("diff=" + (now - lastTime)); location.reload(true); // force a reload from the server } "}^/" either debug [{^-document.write("diff=" + (now - timestamp));^/}][""] {//--></script>^/} ] ]
halt ;; to terminate script if DO'ne from webpage