{"id":149,"date":"2008-05-30T02:19:07","date_gmt":"2008-05-30T07:19:07","guid":{"rendered":"http:\/\/www.jasonmorrison.net\/content\/?p=149"},"modified":"2008-05-30T02:19:07","modified_gmt":"2008-05-30T07:19:07","slug":"a-scary-but-fascinating-idea-javascript-and-css-hack-to-see-where-your-users-have-been","status":"publish","type":"post","link":"http:\/\/www.jasonmorrison.net\/content\/2008\/a-scary-but-fascinating-idea-javascript-and-css-hack-to-see-where-your-users-have-been\/","title":{"rendered":"A Scary, but Fascinating Idea – Javascript and CSS hack to see where your users have been"},"content":{"rendered":"

\"Invasion<\/a><\/p>\n

I just ran across this post on Aza Raskin’s blog<\/a> about a technique used to cut down the number of social bookmarking links displayed to users.\u00a0 I’m sure you’ve seen them–the 20 or so colorful buttons that have popped up at the bottom of every blog post on the web, for Digg, Del.icio.us and similar sites.\u00a0 On my blog they are hidden behind the ShareThis Widget<\/a> but Raskin had a better idea – why not just display the ones each user actually uses?<\/p>\n

Impossible?\u00a0 Not so fast – think about what happens when you visit a site.\u00a0 After your visit any links to the site will change, usually from blue to purple.\u00a0 We can put up links to each social bookmarking site and then use Javascript and CSS to check to see if each link has been visited.\u00a0 If so, display the button, and if not, hide it.<\/p>\n

This is a very cool way to manage buttons but the technique has wider privacy implications.\u00a0 I could, for example, put links to…\u00a0 questionable sites, and then use some Ajax to collect that information about users.\u00a0 If I had other information about you (say you logged into my site or otherwise gave me an email address) I could link it together and build a database.<\/p>\n

On the other hand, it’s not like I can grab your entire browsing history or follow you around after you leave my site – I have to specifically create a link and check it for every site I want to know about.\u00a0 And unlike your browser history this info is cleared every time you close your browser.\u00a0 So it’s not spyware or anything as intrusive as, say, the Alexa toolbar.<\/p>\n

I can think of a bunch of cool ways to apply this technique, but I’m not sharing until I implement one.\u00a0 Feel free to post any ideas (or misgivings) in the comments below.<\/p>\n","protected":false},"excerpt":{"rendered":"

I just ran across this post on Aza Raskin’s blog about a technique used to cut down the number of social bookmarking links displayed to users.\u00a0 I’m sure you’ve seen them–the 20 or so colorful buttons that have popped up at the bottom of every blog post on the web, for Digg, Del.icio.us and similar […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[19],"tags":[262,259,258,257,260,263,261,103,221,758,46],"class_list":["post-149","post","type-post","status-publish","format-standard","hentry","category-blog","tag-ajax","tag-css","tag-delicious","tag-digg","tag-javascript","tag-privacy","tag-sharethis","tag-social-bookmarking","tag-spyware","tag-web-design","tag-web-development"],"aioseo_notices":[],"_links":{"self":[{"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/posts\/149","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/comments?post=149"}],"version-history":[{"count":0,"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/posts\/149\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/media?parent=149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/categories?post=149"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.jasonmorrison.net\/content\/wp-json\/wp\/v2\/tags?post=149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}