Tags: frame

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Tuesday, March 24th, 2020

Oh, embed!

I wrote yesterday about how messing about on your own website can be a welcome distraction. I did some tinkering with adactio.com on the weekend that you might be interested in.

Let me set the scene…

I’ve started recording and publishing a tune a day. I grab my mandolin, open up Quicktime and make a movie of me playing a jig, a reel, or some other type of Irish tune. I include a link to that tune on The Session and a screenshot of the sheet music for anyone who wants to play along. And I embed the short movie clip that I’ve uploaded to YouTube.

Now it’s not the first time I’ve embedded YouTube videos into my site. But with the increased frequency of posting a tune a day, the front page of adactio.com ended up with multiple embeds. That is not good for performance—my Lighthouse score took quite a hit. Worst of all, if a visitor doesn’t end up playing an embedded video, all of the markup, CSS, and JavaScript in the embedded iframe has been delivered for nothing.

Meanwhile over on The Session, I’ve got a strategy for embedding YouTube videos that’s better for performance. Whenever somebody posts a link to a video on YouTube, the thumbnail of the video is embedded. Only when you click the thumbnail does that image get swapped out for the iframe with the video.

That’s what I needed to do here on adactio.com.

First off, I should explain how I’m embedding things generally ‘round here. Whenever I post a link or a note that has a URL in it, I run that URL through a little PHP script called getEmbedCode.php.

That code checks to see if the URL is from a service that provides an oEmbed endpoint. A what-Embed? oEmbed!

oEmbed is like a minimum viable read-only API. It was specced out by Leah and friends years back. You ping a URL like this:

http://example.com/oembed?url=https://example.com/thing

In this case http://example.com/oembed is the endpoint and url is the value of a URL from that provider. Here’s a real life example from YouTube:

https://www.youtube.com/oembed?url=https://www.youtube.com/watch?v=-eiqhVmSPcs

So https://www.youtube.com/oembed is the endpoint and url is the address of any video on YouTube.

You get back some JSON with a pre-defined list of values like title and html. That html payload is the markup for your embed code.

By default, YouTube sends back markup like this:

<iframe
width="480"
height="270"
src="https://www.youtube.com/embed/-eiqhVmSPcs?feature=oembed"
frameborder="0
allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture"
allowfullscreen>
</iframe>

But now I want to use an img instead of an iframe. One of the other values returned is thumbnail_url. That’s the URL of a thumbnail image that looks something like this:

https://i.ytimg.com/vi/-eiqhVmSPcs/hqdefault.jpg

In fact, once you know the ID of a YouTube video (the ?v= bit in a YouTube URL), you can figure out the path to multiple images of different sizes:

(Although that last one—maxresdefault.jpg—might not work for older videos.)

Okay, so I need to extract the ID from the YouTube URL. Here’s the PHP I use to do that:

parse_str(parse_url($url, PHP_URL_QUERY), $arguments);
$id = $arguments['v'];

Then I can put together some HTML like this:

<div>
<a class="videoimglink" href="'.$url.'">
<img width="100%" loading="lazy"
src="https://i.ytimg.com/vi/'.$id.'/default.jpg"
alt="'.$response['title'].'"
srcset="
https://i.ytimg.com/vi/'.$id.'/mqdefault.jpg 320w,
https://i.ytimg.com/vi/'.$id.'/hqdefault.jpg 480w,
https://i.ytimg.com/vi/'.$id.'/maxresdefault.jpg 1280w
">
</a>
</div>

Now I’ve got a clickable responsive image that links through to the video on YouTube. Time to enhance. I’m going to add a smidgen of JavaScript to listen for a click on that link.

Over on The Session, I’m using addEventListener but here on adactio.com I’m going to be dirty and listen for the event directly in the markup using the onclick attribute.

When the link is clicked, I nuke the link and the image using innerHTML. This injects an iframe where the link used to be (by updating the innerHTML value of the link’s parentNode).

onclick="event.preventDefault();
this.parentNode.innerHTML='<iframe src=https://www.youtube-nocookie.com/embed/'.$id.'?autoplay=1></iframe>'"

But notice that I’m not using the default YouTube URL for the iframe. That would be:

https://www.youtube.com/embed/-eiqhVmSPcs

Instead I’m swapping out the domain youtube.com for youtube-nocookie.com:

https://www.youtube-nocookie.com/embed/-eiqhVmSPcs

I can’t remember where I first came across this undocumented parallel version of YouTube that has, yes, you guessed it, no cookies. It turns out that, not only is the default YouTube embed code bad for performance, it is—unsurprisingly—bad for privacy too. So the youtube-nocookie.com domain can protect your site’s visitors from intrusive tracking. Pass it on.

Anyway, I’ve got the markup I want now:

<div>
<a class="videoimglink" href="https://www.youtube.com/watch?v=-eiqhVmSPcs"
onclick="event.preventDefault();
this.parentNode.innerHTML='<iframe src=https://www.youtube-nocookie.com/embed/-eiqhVmSPcs?autoplay=1></iframe>'">
<img width="100%" loading="lazy"
src="https://i.ytimg.com/vi/-eiqhVmSPcs/default.jpg"
alt="The Banks Of Lough Gowna (jig) on mandolin"
srcset="
https://i.ytimg.com/vi/-eiqhVmSPcs/mqdefault.jpg 320w,
https://i.ytimg.com/vi/-eiqhVmSPcs/hqdefault.jpg 480w,
https://i.ytimg.com/vi/-eiqhVmSPcs/maxresdefault.jpg 1280w
">
</a>
</div>

The functionality is all there. But I want to style the embedded images to look more like playable videos. Time to break out some CSS (this is why I added the videoimglink class to the YouTube link).

.videoimglink {
    display: block;
    position: relative;
}

I’m going to use generated content to create a play button icon. Because I can’t use generated content on an img element, I’m applying these styles to the containing .videoimglink a element.

.videoimglink::before {
    content: '▶';
}

I was going to make an SVG but then I realised I could just be lazy and use the unicode character instead.

Right. Time to draw the rest of the fucking owl:

.videoimglink::before {
    content: '▶';
    display: inline-block;
    position: absolute;
    background-color: var(--background-color);
    color: var(--link-color);
    border-radius: 50%;
    width: 10vmax;
    height: 10vmax;
    top: calc(50% - 5vmax);
    left: calc(50% - 5vmax);
    font-size: 6vmax;
    text-align: center;
    text-indent: 1vmax;
    opacity: 0.5;
}

That’s a bunch of instructions for sizing and positioning. I’d explain it, but that would require me to understand it and frankly, I’m not entirely sure I do. But it works. I think.

With a translucent play icon positioned over the thumbnail, all that’s left is to add a :hover style to adjust the opacity:

.videoimglink:hover::before,
.videoimglink:focus::before {
    opacity: 0.75;
}

Wheresoever thou useth :hover, thou shalt also useth :focus.

Okay. It’s good enough. Ship it!

The Banks Of Lough Gowna (jig) on mandolin

If you embed YouTube videos on your site, and you’d like to make them more performant, check out this custom element that Paul made: Lite YouTube Embed. And here’s a clever technique that uses the srcdoc attribute to get a similar result (but don’t forget to use the youtube-nocookie.com domain).

Tuesday, March 3rd, 2020

Visitors, Developers, or Machines

Garrett’s observation is spot-on here:

I’ve been trying to understand the appeal of these frameworks by giving them an objective chance. I’ve expanded my knowledge of JavaScript and tried to give them the benefit of the doubt. They do have their places, but the only explanation I can come up with is that developers are taking a similar approach as Ruby and focusing on developer convenience and productivity. Only, instead of Ruby’s performance being tied to the CPU level, JavaScript frameworks push the performance burden to the client.

In both cases, the tradeoff happens in the name of developer happiness and productivity, but the strategies have entirely different consequences. With Ruby, the CPU is still (mostly) the responsibility of the development team, and it can be upgraded. With JavaScript, the page weight becomes an externality pushed onto visitors.

Tuesday, November 19th, 2019

Modest JS Works | You were never sold on heavy-handed JavaScript approaches. Here’s a case for keeping your JS modest.

The fat JavaScript stacks-du-jour have a lot of appeal. They promise you to be able to do more with less. But what if I want to do less?

This is a terrific little (free!) online book all about modest JavaScript. The second part has practical code, but it’s the first part—all about the principles of staying lean—that really resonates with me.

Don’t build more JS than you can maintain over the long term. If you’re going to be building something for a long time, make sure what you are building will grow with you. Make sure you don’t depend on other people’s work too much, lest you want to keep refactoring your code when the framework you picked goes out of style.

Monday, November 11th, 2019

JavaScript | 2019 | The Web Almanac by HTTP Archive

It’s time for a look at the state of the web when it comes to JavaScript usage. Here’s the report powered by data from HTTP Archive:

JavaScript is the most costly resource we send to browsers; having to be downloaded, parsed, compiled, and finally executed. Although browsers have significantly decreased the time it takes to parse and compile scripts, download and execution have become the most expensive stages when JavaScript is processed by a web page.

Sending smaller JavaScript bundles to the browser is the best way to reduce download times, and in turn improve page performance. But how much JavaScript do we really use?

When it comes to frameworks and UI libraries, there are some interesting numbers. Given the volume of chatter in the dev world, you’d be forgiven for thinking that React is used on the majority of websites today. The real number? 4.6% of websites. That’s less than the number of websites using CSS custom properties.

This is reminding me of what I wrote about dev perception.

Thursday, November 7th, 2019

Tuesday, October 29th, 2019

Using the Platform | TimKadlec.com

Tim ponders the hard work that goes into adding standards to browsers, giving us a system with remarkable longevity.

So much care and planning has gone into creating the web platform, to ensure that even as new features are added, they’re added in a way that doesn’t break the web for anyone using an older device or browser. Can you say the same for any framework out there?

His parting advice is perfect:

Use the platform until you can’t, then augment what’s missing. And when you augment, do so with care because the responsibility of ensuring the security, accessibility, and performance that the platform tries to give you by default now falls entirely on you.

Tuesday, October 8th, 2019

You really don’t need all that JavaScript, I promise

The transcript of a fantastic talk by Stuart. The latter half is a demo of Portals, but in the early part of the talk, he absolutely nails the rise in popularity of complex front-end frameworks:

I think the reason people started inventing client-side frameworks is this: that you lose control when you load another page. You click on a link, you say to the browser: navigate to here. And that’s it; it’s now out of your hands and in the browser’s hands. And then the browser gives you back control when the new page loads.

Wednesday, September 18th, 2019

Keeping it simple with CSS that scales - Andy Bell

The transcript of Andy’s talk from this year’s State Of The Browser conference.

I don’t think using scale as an excuse for over-engineering stuff—especially CSS—is acceptable, even for huge teams that work on huge products.

Friday, August 9th, 2019

Redux: Lazy loading youtube embeds

Remy has an excellent improvement on that article I linked to yesterday on using srcdoc with iframes. Rather than using srcdoc instead of src, you can use srcdoc as well as src. That way you can support older browsers too!

Thursday, August 8th, 2019

Lazy load embedded YouTube videos - DEV Community 👩‍💻👨‍💻

This is a clever use of the srcdoc attribute on iframes.

Native lazy-loading for the web  |  web.dev

The title is somewhat misleading—currently it’s about native lazy-loading for Chrome, which is not (yet) the web.

I’ve just been adding loading="lazy" to most of the iframes and many of the images on adactio.com, and it’s working a treat …in Chrome.

Thursday, August 1st, 2019

The web without the web - DEV Community 👩‍💻👨‍💻

I love React. I love how server side rendering React apps is trivial because it all compiles down to vanilla HTML rather than web components, effectively turning it into a kickass template engine that can come alive. I love the way you can very effectively still do progressive enhancement by using completely semantic markup and then letting hydration do more to it.

I also hate React. I hate React because these behaviours are not defaults. React is not gonna warn you if you make a form using divs and unlabelled textboxes and send the whole thing to a server. I hate React because CSS-in-JS approaches by default encourage you to write completely self contained one off components rather than trying to build a website UI up as a whole. I hate the way server side rendering and progressive enhancement are not defaults, but rather things you have to go out of your way to do.

An absolutely brilliant post by Laura on how the priorites baked into JavaScript tools like React are really out of whack. They’ll make sure your behind-the-scenes code is super clean, but not give a rat’s ass for the quality of the output that users have to interact with.

And if you want to adjust the front-end code, you’ve got to set up all this tooling just to change a div to a button. That’s quite a barrier to entry.

In elevating frontend to the land of Serious Code we have not just made things incredibly over-engineered but we have also set fire to all the ladders that we used to get up here in the first place.

AMEN!

I love React because it lets me do my best work faster and more easily. I hate React because the culture around it more than the library itself actively prevents other people from doing their best work.

Wednesday, July 31st, 2019

The Real Dark Web

Charlie’s thoughts on dev perception:

People speak about “the old guard” and “stupid backwards techniques”, forgetting that it’s real humans, with real constraints who are working on these solutions. Most of us are working in a “stupid backwards way” because that “backwardsness” WORKS. It is something that is proven and is clearly documented. We can implement it confident that it will not disappear from fashion within a couple of years.

Tuesday, July 30th, 2019

Don’t build that app! – Luke Jackson - YouTube

This is a fascinating look at how you can get the benefits of React and npm without using React and npm.

Here’s an accompanying article on the same topic.

Don't build that app! – Luke Jackson

Thursday, July 25th, 2019

What I Like About Vue - daverupert.com

Dave enumerates the things about Vue that click for him. The component structure matches his mental model, and crucially, it’s relative straightforward to add Vue to an existing project instead of ripping everything out and doing things a certain way:

In my experience Angular, React, and a lot of other frameworks ultimately require you to go all in early and establish a large toolchain around these frameworks.

Sunday, July 21st, 2019

Frontend Design, React, and a Bridge over the Great Divide

Brad describes how he has found his place in the world of React, creating UI components without dabbling in business logic:

Instead of merely creating components’ reference HTML, CSS, and presentational JS, frontend designers can create directly consumable HTML, CSS, and presentational JS that back-of-the-frontend developers can then breathe life into.

What’s clear is that the term “React” has become as broad and undefined as the term “front-end”. Just saying that someone does React doesn’t actually say much about the nature of the work.

When you say “we’re hiring a React developer”, what exactly do you mean by that? “React developer” is almost as vague as “frontend developer”, so clarify. Are you looking for a person to specialize in markup and styles? A person to author middleware and business logic? A person to manage data and databases? A person to own build processes?

Friday, July 19th, 2019

Micro Frontends

Chris succinctly describes the multiple-iframes-with-multiple-codebases approach to web development, AKA “micro frontends”:

The idea really is that you might build a React app and I build a Vue app and we’ll slap ‘em together on the same page. I definitely come from an era where we laughed-then-winced when we found sites that used multiple versions of jQuery on the same page, plus one thing that loaded all of MooTools and Prototype thrown on there seemingly by accident. We winced because that was a bucket full of JavaScript, mostly duplicated for no reason, causing bugs and slowing down the page. This doesn’t seem all that much different.

Thursday, July 18th, 2019

Ralph Lavelle: On resilience

Thoughts on frameworks, prompted by a re-reading of Resilient Web Design. I quite like the book being described as a “a bird’s-eye view of the whole web design circus.”

Monday, July 1st, 2019

Why Did I Have Difficulty Learning React? - Snook.ca

When people talk about learning React, I think that React, in and of itself, is relatively easy to understand. At least, I felt it was. I have components. I have JSX. I hit some hiccups with required keys or making sure I was wrapping child elements properly. But overall, I felt like I grasped it well enough.

Throw in everything else at the same time, though, and things get confusing because it’s hard at first to recognize what belongs to what. “Oh, this is Redux. That is React. That other thing is lodash. Got it.”

This resonates a lot with Dave’s post:

React is an ecosystem. I feel like it’s a disservice to anyone trying to learn to diminish all that React entails. React shows up on the scene with Babel, Webpack, and JSX (which each have their own learning curve) then quickly branches out into technologies like Redux, React-Router, Immutable.js, Axios, Jest, Next.js, Create-React-App, GraphQL, and whatever weird plugin you need for your app.

Sunday, June 16th, 2019

When should you be using Web Workers? — DasSur.ma

Although this piece is ostensibly about why we should be using web workers more, there’s a much, much bigger point about the growing power gap between the devices we developers use and the typical device used by the rest of the planet.

While we are getting faster flagship phones every cycle, the vast majority of people can’t afford these. The more affordable phones are stuck in the past and have highly fluctuating performance metrics. These low-end phones will mostly likely be used by the massive number of people coming online in the next couple of years. The gap between the fastest and the slowest phone is getting wider, and the median is going down.