reiver-frames-protocol/index.xhtml

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HTML

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta charset="utf-8" />
<title>Frames Protocol</title>
</head>
<body>
<main>
<article>
<h1>Frames Protocol</h1>
<address class="h-card">
by
<a rel="author" class="u-url" href="http://changelog.ca/"><span class="p-given-name">Charles</span> <span class="p-additional-name">Iliya</span> <span class="p-family-name">Krempeaux</span></a>
</address>
<p>
The <strong>Frames Protocol</strong>, also known <strong>Farcaster Frames</strong>, is a simple web-based technology used for making applications.
</p>
<p>
Although the <strong>Frames Protocol</strong> <em>could</em> be used outside of <strong>Farcaster</strong>, at the time of writing, <strong>Farcaster</strong> clients are the only major (client-side) platform to support it.
</p>
<p>
(The server-side of the <strong>Frames Protocol</strong>, which is called a <strong>Frame Server</strong>, is an HTTP resource — which some might loosely call an HTTP (or HTTP) URL.)
</p>
<section>
<h2>Farcaster</h2>
<p>
Before we get into the <strong>Frames Protocol</strong> let's quickly go over <strong>Farcaster</strong> — since the <strong>Frames Protocol</strong> originated with <strong>Farcaster</strong>.
</p>
<p>
<strong>Farcaster</strong> is a decentralized social-media network — and is similar in many ways to other decentralized social-media networks, such as
the <strong>Fediverse</strong> (which includes Mastodon, Pleroma, Pixelfed, PeerTube, Misskey, Lemmy, Kbin, GreatApe, Akkoma, etc),
and
<strong>Bluesky</strong>.
</p>
<p>
And in particular, <strong>Farcaster</strong> is a <strong>micro-blogging</strong> social-media network platform.
</p>
<p>
The most famous <strong>micro-blogging</strong> social-media network platform is <strong>Twitter.</strong>.
But the <strong>Fediverse</strong>'s <strong>Mastodon</strong>, <strong>Akkoma</strong>, <strong>Misskey</strong>, <strong>Pleroma</strong> and others are also <strong>micro-blogging</strong> social-media network platforms.
And so too is <strong>Bluesky</strong>.
</p>
<p>
All of these (including <strong>Farcaster</strong>) are similar to <strong>Twitter.</strong>.
</p>
</section>
<section>
<h2>HTML</h2>
<p>
One of the main languages of the <abbr title="World Wide Web">Web</abbr> is <abbr title="HyperText Markup Language">HTML</abbr>.
</p>
<p>
<abbr title="HyperText Markup Language">HTML</abbr> looks like this:
</p>
<pre><code>
The following is &lt;b&gt;bold&lt;/b&gt; and &lt;a href="http://example.com/"&gt;this&lt;/a&gt; is a link.
</code></pre>
<p>
Although typically, <abbr title="HyperText Markup Language">HTML</abbr> comes as a whole page (rather than a fragment), and thus usually looks more like this:
</p>
<pre><code>
&lt;!DOCTYPE html&gt;
&lt;html xmlns="http://www.w3.org/1999/xhtml" lang="en"&gt;
&lt;head&gt;
&lt;meta charset="utf-8" /&lt;
&lt;title&gt;An Example&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
&lt;p&gt;
The following is &lt;b&gt;bold&lt;/b&gt; and &lt;a href="http://example.com/"&gt;this&lt;/a&gt; is a link.
&lt;/p&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>
<p>
The <strong>Frames Protocol</strong> actually only uses a tiny part of HTML.
</p>
</section>
<section>
<h2>HTML &lt;meta&gt; Element</h2>
<p>
When creating a <strong>Frames Protocol</strong> application, you can effectively ignore almost all of <abbr title="HyperText Markup Language">HTML</abbr> except for one <abbr title="HyperText Markup Language">HTML</abbr> element — the <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element.
</p>
<p>
The <strong>Frames Protocol</strong> only uses the <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element.
And it (the <strong>Frames Protocol</strong>) uses the <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element in a very particular way.
</p>
<p>
The <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element has been around since the 1990s.
</p>
<p>
If you look at the old <abbr title="HyperText Markup Language">HTML</abbr> 2.0 specification (i.e., <a href="https://datatracker.ietf.org/doc/html/rfc1866">IETC RFC-1866</a> in <a href="https://datatracker.ietf.org/doc/html/rfc1866#section-5.2.5">section 5.2.5.</a>), which was created back in the 1990s, you can see how the <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element was defined back then.
</p>
</section>
<section>
<h2>OpenGraph</h2>
<p>
The <strong>Frames Protocol</strong> usage of the <abbr title="HyperText Markup Language">HTML</abbr> &lt;meta&gt; element takes inspiration from the <a href="https://ogp.me/">OpenGraph</a> protocol.
</p>
<p>
Here is an example of the <a href="https://ogp.me/">OpenGraph</a> protocol:
</p>
<pre><code>
&lt;!DOCTYPE html&gt;
&lt;html xmlns="http://www.w3.org/1999/xhtml" lang="en"&gt;
&lt;head&gt;
&lt;meta charset="utf-8" /&lt;
&lt;meta property="og:title" content="Hello world!" /&gt;
&lt;meta property="og:type" content="article" /&gt;
&lt;meta property="og:image" content="/images/4aigvXF62jMY8iRzFN8x.jpeg" /&gt;
&lt;meta property="og:url" content="http://www.example.com/article/hello-world.xhtml" /&gt;
&lt;title&gt;An Example&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
&lt;p&gt;
The following is &lt;b&gt;bold&lt;/b&gt; and &lt;a href="http://example.com/"&gt;this&lt;/a&gt; is a link.
&lt;/p&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>
<p>
Since there is a lot of <abbr title="HyperText Markup Language">HTML</abbr> code there, let's just focus on the <a href="https://ogp.me/">OpenGraph</a> part of it:
</p>
<pre><code>
&lt;meta property="og:title" content="Hello world!" /&gt;
&lt;meta property="og:type" content="article" /&gt;
&lt;meta property="og:image" content="/images/4aigvXF62jMY8iRzFN8x.jpeg" /&gt;
&lt;meta property="og:url" content="http://www.example.com/article/hello-world.xhtml" /&gt;
</code></pre>
<p>
It is rather simple.
It is just name-value pairs.
</p>
</section>
</article>
</main>
</body>
</html>