elsewhere

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A node project that aims to replicate the functionality of the Google Social Graph API

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To use Elsewhere, simply provide it with a URL. Elsewhere will use this target as the entry point to the graph and will search it for links that contain the attribute <a href='http://microformats.org/wiki/rel-me'><code>rel=me</code></a>: <pre><code><a href="http://dharmafly.com" rel="me">Dharmafly</a></code></pre> The <code>rel=me</code> attribute is a microformat to assert that the link is to a website, page or resource that is owned by (or is about) the same person as the page the link is on. For example, if you’ve given Elsewhere a URL that’s a Twitter profile, they usually contain a link to that person or company’s webpage; this link has the <code>rel=me</code> microformat. When Elsewhere finds a <code>rel=me</code> link or links at a URL, it searches each of them for more, building a comprehensive graph along the way. For example, a person’s Twitter profile page may link to his or her home page, which in turn links to their Last.fm, Flickr, Facebook, GitHub, LinkedIn, Google+ profiles etc. Elsewhere can only search public profiles and webpages for links. If a page isn’t public, Elsewhere can’t search it for links. It’s also worth noting that profile owners deliberately place these links on their profiles to make them discoverable. If the profile owner has neglected to place a link there, Elsewhere won’t find one. Once Elsewhere has run out of new <code>rel=me</code> links to search, it returns a list of all the URLs it has found. This list is what is referred to as the ‘social graph’, the owner of which being the owner of the URL you initially gave Elsewhere. <h2 id='strict_mode_and_verified_links'>Strict Mode and verified links</h2> Elsewhere can make strict checks to verify that that each linked URL is indeed owned by the same person as the original site. After all, anyone could create a website, add a <code>rel=me</code> link to <a href='http://www.elvis.com'>Elvis Presley</a>’s website and claim to be him. Elsewhere checks if the linked page itself has a <code>rel=me</code> link back to the original URL. If there is such a reciprocal link, then the relationship is deemed to be ‘verified’. But Elsewhere is more sophisticated than that. The reciprocal link doesn’t have to be directly between the two sites. For example, if a Twitter account links to a GitHub account, which links to a home page, which links back to the Twitter account, then the relationship between the Twitter account and home page will be verified, even though the two don’t directly link to each other. Elsewhere operates in non-strict mode by default, in which it will return both verified and unverified URLs. This mode is useful because many profile pages and personal websites lack <code>rel=me</code> links, making it difficult to verify those links and leading to many legitimate links being missed. To be absolutely sure of the stated relationships, turn on strict mode (by setting the <code>strict</code> option to <code>true</code>) and only verified URLs will be returned. <h2 id='url_shortners_and_redirects'>URL shortners and redirects</h2> When elsewhere follows a link and that link resolves to a different URL, that new resolved URL takes precedence over the original. For instance: <pre><code>http://github.com/chrisnewtn -> https://github.com/chrisnewtn http://t.co/vV5BWNxil2 -> http://chrisnewtn.com</code></pre> The original links to a page are still shown in the graph in that page’s <code>urlAliases</code> collection, but as far as the rest of the graph is concerned, that link is now known by its resolved name. Were URL shorteners and redirects ignored, you’d end up with a situation where both <code>http://github.com/user</code> and <code>https://github.com/user</code> were in your graph as two seperate pages, which is clearly incorrect.