WEBVTT captioned by ken, checked by sachac
NOTE Overview
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Hello, I am Yuchen, and I will be talking about
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how Emacs may be used to save user freedom on the web.
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I will begin by describing the background issues,
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followed by solutions outside of Emacs.
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Then I will move into the main business of describing
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several ways to address the issues using Emacs,
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including free clients in Emacs, web browsers,
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also known as universal clients in Emacs,
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approaches using Emacs web server and Emacs web framework,
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which allows one to write an Emacs package
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and get a web app for free,
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as well as using Emacs as a Firefox extension.
NOTE Background problems
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OK, let's now move on to
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the background issues for this topic.
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Many of you probably already know what is free software.
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It is software that respects four user freedoms,
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including freedom 0, which is the freedom to use,
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freedom 1 is the freedom to study and modify a program,
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freedom 2 is the freedom to
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distribute exact copies of a program,
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and freedom 3 is the freedom to distribute modified copies.
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Different environments have different norms
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with regards to user freedom.
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For example, GNU/Linux distributions
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default to free software,
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even though the official kernel Linux
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contains non-free code, like non-free firmware.
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What I mean is, people generally expect free software
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in these environments.
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There's plenty of free software
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built on other free software,
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so generally people can accomplish tasks
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using free software only.
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Emacs, by comparison, is even better.
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It has freedom built-in, as it is highly customizable
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with self-documenting configurations.
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When a Lisp form is evaluated by the user in Emacs,
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the change is instantly reflected in the environment.
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Thus, it converts users to hackers effortlessly.
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From writing setq statements,
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which is similar to configurations
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in the majority of other programs,
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to writing functions,
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which are building blocks of Elisp features,
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to writing features and publishing packages,
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it is a natural progression.
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In this sense, Emacs perhaps has
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the most gentle learning curve for hackers.
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On the other hand, the default license
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in the Emacs community
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is GNU General Public License version 3 or later,
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which is the best free software license
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apart from the Affero license.
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Now let's move on to web browsers,
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which by contrast does not default to freedom.
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For one thing, free software JavaScript projects
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default to Expat license,
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which is also commonly known as the MIT license,
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which is a lax permissive license that could be exploited
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as developers could write non-free derivatives
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and subjugate user freedom.
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This also contributes to the JavaScript trap.
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Most popular web browsers nowadays simply download and run
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any JavaScript code requested by the web page.
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Generally speaking, there are two camps on this issue.
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One side would say JavaScript is simply part of life,
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and an integral part of the so-called modern web.
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Just accept it, and there is no point in fighting it.
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Indeed, it can be frustrating when greeted by
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"This page requires JavaScript and cookies to continue,"
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or even a blank page when opening a web page
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while disabling JavaScript.
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The other camp takes a more principled position
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and says JavaScript is unnecessary.
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I mean, people use the web mainly for
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database-like operations
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to interact with data stored on other people's computers,
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like querying, creating, updating, deleting.
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I mean, 99% of the things happen in getting data,
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including reading news, watching videos,
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downloading images, etc.,
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and posting data, including publishing
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this sort of materials, publishing news comments, videos.
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Why does this need any programs
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to do funny computations, right?
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Modern web browsers are also a pain to use.
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They are the opposite to Emacs
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in terms of customization capabilities.
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Such problems on the client side
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is the main focus of this talk.
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On the server side, the issue is known as SaaSS,
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service as a software substitute.
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It is about doing computing for users
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on other people's computers,
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which the user has no visibility, let alone control.
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Examples include translation or photo editing
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in so-called web applications.
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Another example would be web applications
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make recommendations based on user data
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and suggest what the users read or watch next.
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On the one hand, SaaSS is an intractable problem
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because free software is all about user freedom
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on one's own computer,
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not someone else's computer.
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On the other hand, this is also a lesser problem
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because it has trivial solutions,
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which is self-hosting and keeping computations local.
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Wouldn't it be nice to use a photo editing web application,
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but without the web?
NOTE Solutions outside of Emacs
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Right, now let's move on to solutions outside of Emacs
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that tackle these problems.
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There are generally two ways to fix this issue.
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One is blocking non-free JavaScript,
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and the other is substituting with free programs.
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Let's start with blocking.
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LibreJS, for example, is a Firefox extension
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blocking non-free, non-trivial JavaScript.
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It works by intercepting, filtering
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all requests for JavaScript,
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recognizing the ones that are trivial or free,
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and blocking the execution of the others.
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As an experiment, I logged the LibreJS output
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for about two weeks,
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and during which, of all the web pages I loaded,
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23 domains have at least some LibreJS-compliant scripts.
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That is not much, though I did use other means
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to reduce the scenarios
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where I need to load web pages with JavaScript in Firefox,
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like using a text browser like Lynx.
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Then there's also NoScript, which is like LibreJS,
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but it blocks all scripts, whether free or non-free,
trivial or non-trivial.
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So the problem with blocking is that
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blocking with certain scripts and accepting others,
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there are like... I can think of two problems.
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One is that it does not help with Freedom 1,
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which is the freedom to allow users to modify a program
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and use it in place of the original program.
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And also it does not help
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when the non-free JavaScript is mandatory
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for the functioning of the web page.
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For example, some pages are blank
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when non-free JavaScript is not executed.
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So now let's move on to the substitution, the other method.
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Let's start with userscript.
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It is a script, it is a user-specified JavaScript
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injected to a web page.
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A typical example of userscript tool is GreaseMonkey.
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Another idea is a proxy that replaces scripts in place,
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that is, sending user-specified scripts
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as a response to requests for such scripts.
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So one example would be Haketilo, however you pronounce it.
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It's a tool that's built on top of mitmproxy.
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It is supposed to do this.
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I haven't used GreaseMonkey nor Haketilo
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for these purposes yet,
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so I can't say much about these options.
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So then there are also free clients
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which replace the whole frontend,
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instead of a script requested by web pages
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from the official web clients.
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People often refer to them as alternative frontend.
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YouTube is perhaps the best example
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as there are so many free clients,
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including Invidious for the web,
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youtube-dl and yt-dlp on the command line,
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MPV and VLC as GUI desktop, LibreTube
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and NewPipe for Android and so on.
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Youtube-dl and yt-dlp are especially versatile
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as they work with many video and audio sites
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with extractors written in Python,
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so people can add extractors like extensions.
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A similar tool would be woob,
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short for web outside of the browsers.
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It is a command-line and GUI program
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that interacts with many web services, even banks.
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And there are browser extensions
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that automatically redirect to these clients.
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For example, Redirector and Libredirect
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redirect to the free web clients.
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One could use OpenWith, another extension,
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to redirect to free non-web clients,
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for example by opening YouTube links with MPV.
NOTE Emacs solutions
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Now let us move to Emacs-based solutions.
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They are based on the same ideas but using Emacs.
NOTE Free clients in Emacs
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First, free clients in Emacs.
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Basically alternative frontends written in Elisp.
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There are several advantages.
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For example, integration with other Emacs tools,
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good for archiving, making use of Emacs libraries,
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extensibility, thanks to Emacs' own
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extensibility and customizability.
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Examples include mastodon.el for mastodon,
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or mastorg for viewing and archiving toots with org,
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sx for Stack Exchange, buildbot.el for buildbot, etc.
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Here's an example of mastorg displaying
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the hierarchy of a toot in org.
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Just wait. Right.
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So this is the toot itself, this is a first reply,
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this is a reply to the reply, and so on.
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And here is an example of
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opening a Stack Exchange link using sx.
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Let's check out the tag.
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So we can browse the Stack Exchange Emacs site
with ease.
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The idea is quite simple.
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Just use APIs to get data and display it in Emacs,
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or just to scrape, like requesting HTML and processing it.
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An example of scraping is hnreader,
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which scrapes Hacker News web pages
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and renders them in Org buffers.
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Here's how hnreader fetches
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and displays the Hacker News front page.
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And one could go into the comments,
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which shows a similar hierarchy to mastorg's output.
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And of course, there are limitations for this method,
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which is not limited to Emacs.
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There are basically limitations
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to any ad hoc bespoke clients,
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which is catch-up games with remote server,
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which may change the API interface endpoints
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or even structure of the responses.
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This brings us to web browsers in Emacs.
NOTE Web browsers in Emacs
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Web browsers are universal clients
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because all sites support browsers.
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So in a world of no JavaScript,
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there will be no need to write bespoke clients.
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In such a world,
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instead of using JavaScript code to fetch JSON,
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web developers make server do the heavy lifting
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and just send the complete HTML over.
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Okay, back to reality.
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EWW, the default Emacs browser,
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is what people refer to as a text browser,
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even though it is not text only and it supports images too.
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It is a good solid browser that supports forms, etc.
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The downside is that it does not support CSS,
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so the formatting could be a bit ugly sometimes.
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There are some other browsers in Emacs too,
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like emacs-w3m, which is backed by w3m,
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and Luwak, which is backed by Lynx.
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Sorry for the naming, by the way.
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They often consist of a backend
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that fetches URL and parses HTML.
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For example, the built-in URL package
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and the libxml2 binding in Emacs are decent enough.
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And the frontend that renders the HTML,
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like shr or lynx, etc.
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There is also an xwidget-webkit,
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but this browser executes JavaScript,
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so it does not really help in this case.
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Browser extensions on Emacs are effortless,
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as they can be written as Emacs packages.
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For example, one could easily write
00:14:19.280 --> 00:14:21.959
Elisp scripts with similar functionalities
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to libredirect and openwith
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to redirect links, to rewrite URLs,
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or to open, say, a YouTube URL with MPV,
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but with even more flexibility.
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For example, here's how one could
00:14:41.780 --> 00:14:44.839
transform a Zoom link to a dial-in number
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so that it is easier to join a Zoom meeting
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without running non-free JavaScript.
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This might still be bad for privacy,
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but at least it's good for freedom.
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As mentioned before,
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one shortcoming of these Emacs-based browsers,
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Emacs web browsers, is no support for CSS,
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so the formatting could leave a lot to be desired.
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Maybe someone would write
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an Emacs browser package backed by wkhtmltopdf,
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which, when opening a URL,
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it calls wkhtmltopdf to convert the web page to PDF
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and opens in, say, pdf-view-mode of the pdf-tools,
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thus containing formatting,
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and all the URL clicks resolve to the same actions.
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Also, wkhtmltopdf contains a flag that disables JavaScript.
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Another idea would be to use Firefox
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as a processor to fetch URLs.
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Maybe it can be used to pass back the HTML
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after executing free JavaScript,
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say, if Firefox has LibreJS installed.
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This requires Firefox to send back the DOM,
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which could be achieved using native messaging.
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More on that later.
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Alternatively, one could also write a Firefox extension
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that sends the DOM in an existing tab back to Emacs.
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But thinking more about it,
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I don't think this is actually a useful idea,
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because most of the sites that work under LibreJS
00:16:27.139 --> 00:16:34.419
also are useful when all JavaScript is blocked.
00:16:34.420 --> 00:16:37.039
So, this means these sites are viewable
00:16:37.040 --> 00:16:42.159
under EWW, Luwak, etc.
00:16:42.160 --> 00:16:43.639
And another issue is that
00:16:43.640 --> 00:16:46.559
this could also make running non-free JavaScript easier,
00:16:46.560 --> 00:16:52.379
which is harmful to user freedom.
NOTE emacs-web-server - overview
00:16:52.380 --> 00:16:54.239
OK, let's move on to the idea
00:16:54.240 --> 00:16:55.679
of running Emacs as a web server,
00:16:55.680 --> 00:16:58.559
so that Emacs client packages are web apps
00:16:58.560 --> 00:17:00.319
serving as alternative frontends.
00:17:00.320 --> 00:17:02.239
Why would we want to do this?
00:17:02.240 --> 00:17:06.079
Well, as much as one wants to be always in Emacs,
00:17:06.080 --> 00:17:08.339
it is not always feasible.
00:17:08.340 --> 00:17:10.719
For example, one may be on the go
00:17:10.720 --> 00:17:12.519
and needs to look up something on the phone.
00:17:12.520 --> 00:17:14.879
On the other hand, Emacs client packages
00:17:14.880 --> 00:17:16.159
are just alternative frontends
00:17:16.160 --> 00:17:18.119
but written in Elisp and run in Emacs.
00:17:18.120 --> 00:17:20.759
With the help of emacs-web-server package,
00:17:20.760 --> 00:17:23.579
we can access Emacs packages on the web.
00:17:23.580 --> 00:17:26.439
emacs-web-server package is not something new,
00:17:26.440 --> 00:17:30.379
but seems to be underused in the community somehow.
NOTE emacs-web-server - hello emacs!
00:17:30.380 --> 00:17:33.359
OK, let's start with a simple example called hello-emacs.
00:17:33.360 --> 00:17:35.239
It is pretty straightforward.
00:17:35.240 --> 00:17:38.639
Just require the web server feature
00:17:38.640 --> 00:17:40.999
and run ws-start to start a server process
00:17:41.000 --> 00:17:43.359
and send the string "hello emacs"
00:17:43.360 --> 00:17:45.539
to the process regardless of the request.
00:17:45.540 --> 00:17:48.479
As you can see, it is going to be available
00:17:48.480 --> 00:17:51.219
at port 9000 of localhost.
00:17:51.319 --> 00:17:52.999
Let's try it out.
00:17:53.000 --> 00:18:01.839
We need to first evaluate this code block.
00:18:01.840 --> 00:18:03.939
And it works.
00:18:03.940 --> 00:18:10.839
To stop a server, just run ws-stop on the web server object.
00:18:10.840 --> 00:18:14.959
Let's evaluate.
00:18:14.960 --> 00:18:17.579
Yep, it stopped.
NOTE emacs-web-server - yolo
00:18:17.580 --> 00:18:19.999
OK, now let's move on to something funny
00:18:20.000 --> 00:18:22.219
that you should never run on the public web.
00:18:22.220 --> 00:18:23.919
I call it yolo.el.
00:18:23.920 --> 00:18:25.359
It uses htmlize
00:18:25.360 --> 00:18:28.159
to make any Emacs buffer available on the web.
00:18:28.160 --> 00:18:28.999
Let's try it out.
00:18:29.000 --> 00:18:32.999
Just require the thing and start the server by yolo-start.
00:18:33.000 --> 00:18:38.119
And it's available at port 9999.
00:18:38.120 --> 00:18:41.599
By default, the root domain shows the splash screen
00:18:41.600 --> 00:18:42.919
which needs to be available.
00:18:42.920 --> 00:18:46.719
Running display-splash-screen ensures that,
00:18:47.219 --> 00:18:48.839
but here I've already run it.
00:18:48.939 --> 00:18:54.359
So let's have a look.
00:18:54.560 --> 00:18:56.639
And here we have the splash screen.
00:18:56.640 --> 00:19:00.239
Emacs tutorial and such.
00:19:00.240 --> 00:19:03.279
Unfortunately, none of these links work,
00:19:05.480 --> 00:19:08.000
which is something we will revisit later.
00:19:10.000 --> 00:19:15.381
So, to show an arbitrary buffer,
00:19:15.481 --> 00:19:19.981
just use the buffer name as a path.
00:19:20.081 --> 00:19:24.761
For example, the slide has the buffer named web.org,
00:19:24.861 --> 00:19:28.080
so we can display it.
00:19:34.581 --> 00:19:36.540
Let's try something fancier,
00:19:36.941 --> 00:19:40.000
like the man page of ffmpeg.
00:19:40.880 --> 00:19:44.719
So this is the man page of ffmpeg.
00:19:45.120 --> 00:19:48.420
And the buffer name is a bit more complicated.
00:19:48.520 --> 00:19:51.639
I have the URL available here.
00:19:59.140 --> 00:20:05.979
It's missing a star.
00:20:05.980 --> 00:20:10.659
It's pretty neat if you ask me.
00:20:12.560 --> 00:20:14.879
And, yeah, what else?
00:20:14.880 --> 00:20:22.699
Well, we can also browse EWW in Firefox.
00:20:22.700 --> 00:20:30.599
For example, let's check out gnu.org,
00:20:30.600 --> 00:20:33.679
and note that the buffer name is EWW with stars.
00:20:39.080 --> 00:20:41.879
So, ah, it works.
00:20:41.979 --> 00:20:50.899
And it has all the graphics even.
00:20:50.900 --> 00:20:55.639
Now, how about we do it the other way around?
00:20:55.640 --> 00:21:10.779
So we load the current slide web.org using this funny thing.
00:21:10.780 --> 00:21:12.239
And it works.
00:21:14.040 --> 00:21:19.939
Not as nice as the Org buffer, though.
00:21:19.940 --> 00:21:27.439
Right, and now that gives me some funny idea.
00:21:27.440 --> 00:21:31.359
So I'm a firm believer that memes are meant to be enjoyed
00:21:31.360 --> 00:21:33.199
in silence rather than read out loud.
00:21:33.200 --> 00:21:38.759
So I will jump straight to trying this idea,
00:21:38.760 --> 00:21:48.959
which is loading the EWW buffer URL with EWW itself.
00:21:49.860 --> 00:21:53.839
Loading, loading, loading.
00:21:53.840 --> 00:21:56.199
Spoiler alert, it never loads.
00:21:59.100 --> 00:22:03.120
So that concludes the demo.
00:22:03.220 --> 00:22:06.439
And so we can stop the server, web server, with `yolo-stop`.
00:22:06.440 --> 00:22:13.399
So one could extend yolo to serve arbitrary Emacs commands,
00:22:13.400 --> 00:22:15.439
making it even more dangerous.
00:22:15.440 --> 00:22:26.019
That is, for example, `localhost:9000/m-x/magit-status`
00:22:26.119 --> 00:22:27.720
would run `magit-status`
00:22:27.820 --> 00:22:33.499
and show the magit-status buffer in the web browser.
00:22:34.500 --> 00:22:43.119
Or localhost:9000/m-x/eww/
00:22:43.120 --> 00:22:46.759
any arbitrary URL to browse arbitrary URL
00:22:46.760 --> 00:22:50.819
with EWW inside of Firefox.
00:22:50.820 --> 00:22:53.879
It can serve as a way to block all JavaScript,
00:22:53.880 --> 00:22:56.799
because EWW does not support JavaScript.
00:22:56.800 --> 00:23:00.079
And enforce preferred colorscheme in Firefox,
00:23:00.080 --> 00:23:02.839
since htmlize, as you have noticed,
00:23:02.840 --> 00:23:06.439
faithfully reflects the theme used in Emacs.
NOTE emacs-web-server - emacs web framework
00:23:07.940 --> 00:23:10.239
Okay, so we know that yolo is unsafe
00:23:10.339 --> 00:23:11.440
and needs to be refined.
00:23:11.540 --> 00:23:13.439
In fact, we don't necessarily want
00:23:13.440 --> 00:23:15.599
to run Emacs on a web browser.
00:23:15.600 --> 00:23:17.279
After all, a modern web browser is
00:23:17.280 --> 00:23:19.079
something one has to fight all the time
00:23:19.080 --> 00:23:21.600
and should be avoided whenever possible.
00:23:21.601 --> 00:23:24.479
We want to instead be able to access things
00:23:24.480 --> 00:23:26.459
when forced to be in a web browser,
00:23:26.460 --> 00:23:28.359
in which case only the motivations
00:23:28.360 --> 00:23:31.299
of an alternative frontend apply.
00:23:31.300 --> 00:23:35.360
Moreover, the ideal situation is an Emacs web framework,
00:23:35.460 --> 00:23:36.799
a tool that automatically
00:23:36.800 --> 00:23:39.199
transforms Emacs packages to web apps,
00:23:39.200 --> 00:23:41.799
so that one does not need to write extra code
00:23:41.800 --> 00:23:45.559
to get a web app that does the same thing as the package.
00:23:45.560 --> 00:23:49.099
We also need all links in the web pages to work.
00:23:49.100 --> 00:23:52.399
As noted before, the links on the yolo Emacs splash screen
00:23:52.400 --> 00:23:53.839
do not work.
00:23:53.840 --> 00:23:58.199
So here's a proof-of-concept example. It's called bom.el.
00:23:58.200 --> 00:24:00.119
It gets some weather forecast data
00:24:00.120 --> 00:24:03.079
from the Australian Bureau of Meteorology
00:24:03.080 --> 00:24:05.559
and displays it in an org buffer.
00:24:05.560 --> 00:24:09.279
So let's try it out. One could do `M-x bom`,
00:24:09.280 --> 00:24:15.219
which shows an org buffer with links to each state.
00:24:15.220 --> 00:24:17.199
So based in Melbourne, naturally,
00:24:17.200 --> 00:24:21.839
I would like to find out the weather of Victoria.
00:24:21.840 --> 00:24:27.839
And yes, to execute this command. Wait, wait, wait. Right.
00:24:27.840 --> 00:24:33.459
And we are at a buffer that shows
00:24:33.460 --> 00:24:36.119
the weather forecast of the whole of Victoria
00:24:36.120 --> 00:24:39.379
in the hierarchy. Note that this back button
00:24:39.479 --> 00:24:46.639
takes you to the previous page.
00:24:46.640 --> 00:24:47.919
So here are the regions of Victoria.
00:24:47.920 --> 00:24:53.799
I think Melbourne is in Central.
00:24:53.800 --> 00:24:54.719
And yeah, it shows
00:24:54.720 --> 00:24:57.259
the seven-day weather forecast of Melbourne.
00:24:57.260 --> 00:25:00.359
You can also reach this page by running,
00:25:00.360 --> 00:25:08.199
let's see, directly `M-x bom-state`.
00:25:08.600 --> 00:25:09.759
Vic.
00:25:13.960 --> 00:25:18.399
OK. So this works.
00:25:18.400 --> 00:25:21.280
And this is bom as an Emacs package.
00:25:21.380 --> 00:25:23.980
Now let's check out bom as a web app
00:25:23.981 --> 00:25:28.039
transformed by Emacs web framework.
00:25:28.040 --> 00:25:30.319
So start the web server with bom-start.
00:25:33.020 --> 00:25:39.559
And let's try it out. It's at 9000 again.
00:25:39.560 --> 00:25:42.359
Oops. Invalid path. Oh, that's because
00:25:42.360 --> 00:25:46.119
it makes exactly one command to one path.
00:25:46.120 --> 00:25:49.300
So remember that we used the bom command
00:25:49.301 --> 00:25:50.719
to show the landing page.
00:25:50.720 --> 00:25:54.340
So here we need the bom in the path as well.
00:25:54.440 --> 00:26:00.679
And it shows the same landing page, except in HTML.
00:26:00.680 --> 00:26:07.259
Let's check out Victoria weather forecast as before.
00:26:07.260 --> 00:26:12.279
And it shows an HTML converted from the org buffer
00:26:12.280 --> 00:26:17.559
using ox export HTML, whatever.
00:26:17.560 --> 00:26:20.259
And you can see even the back button is here.
00:26:20.359 --> 00:26:26.219
That takes you to /bom.
00:26:26.220 --> 00:26:29.139
So let's have a look at Melbourne. Here it is.
00:26:29.140 --> 00:26:31.379
Hooray, it works.
00:26:31.380 --> 00:26:33.860
So, yeah, as usual,
00:26:33.960 --> 00:26:40.559
you can stop the web server with `M-x bom-stop`.
00:26:40.560 --> 00:26:43.660
Right. And alternatively,
00:26:43.760 --> 00:26:48.499
it can also be deployed directly in terminal
00:26:48.500 --> 00:26:56.099
in a dedicated Emacs daemon.
00:26:56.100 --> 00:26:58.279
So you can see that there's a one-one correspondence
00:26:58.280 --> 00:27:03.099
between the Emacs package interface and the web interface.
00:27:03.100 --> 00:27:06.039
And that implies some restrictions to the Emacs package
00:27:06.040 --> 00:27:09.159
for the Emacs web framework to be able to do its job. Right.
00:27:09.160 --> 00:27:13.439
For example, the package needs to have an Org interface
00:27:13.440 --> 00:27:15.519
and the links that trigger other commands
00:27:15.520 --> 00:27:17.799
need to be in Elisp links
00:27:17.800 --> 00:27:20.759
so that the Emacs web framework
00:27:20.760 --> 00:27:24.799
can translate it to web server URL path.
00:27:24.800 --> 00:27:28.919
Note that Emacs web server framework is not a real package.
00:27:28.920 --> 00:27:33.339
I wrote some functions in bom.el serving the purpose,
00:27:33.340 --> 00:27:35.719
and they should be separated out eventually
00:27:35.720 --> 00:27:37.759
without much trouble.
00:27:37.760 --> 00:27:39.999
One could get weather forecast
00:27:40.000 --> 00:27:42.219
without running JavaScript anyway,
00:27:42.220 --> 00:27:45.199
which makes bom.el less important
00:27:45.200 --> 00:27:48.319
as an alternative web client.
00:27:48.320 --> 00:27:50.519
Though it does provide, dare I say,
00:27:50.520 --> 00:27:52.380
a clean and minimal interface
00:27:52.480 --> 00:27:55.719
compared to common weather forecast web pages.
00:27:55.720 --> 00:27:58.639
Other more relevant use cases could be Mastodon,
00:27:58.640 --> 00:28:01.319
whose official web client requires JavaScript
00:28:01.320 --> 00:28:03.479
to display a post.
00:28:03.480 --> 00:28:08.559
The mastorg package that shows an Org hierarchy of toots
00:28:08.560 --> 00:28:12.079
rooted as a given toot could be a low-hanging fruit.
00:28:12.179 --> 00:28:15.199
The limitation of Org interface requirements
00:28:15.200 --> 00:28:17.879
can also be relaxed in further work,
00:28:17.880 --> 00:28:21.639
if one could extend Emacs web framework
00:28:21.640 --> 00:28:24.199
to translate back and forth between Emacs widgets,
00:28:24.200 --> 00:28:28.639
say, including buttons and web page widgets,
00:28:28.640 --> 00:28:30.599
including links.
00:28:30.600 --> 00:28:32.599
Another more far-fetched idea would be
00:28:32.600 --> 00:28:35.799
to translate to other types of interfaces,
00:28:35.800 --> 00:28:42.120
like GNU/Linux or Android GUI.
00:28:44.020 --> 00:28:47.479
How about animations? Say, M-x butterfly,
00:28:47.480 --> 00:28:53.999
or even web games from Emacs games?
00:28:54.000 --> 00:29:00.099
Possibilities are unlimited in this, as always, in Emacs.
00:29:00.100 --> 00:29:03.159
I also noticed some limitations
00:29:03.160 --> 00:29:07.439
when trying to actually host bom.el on the public web.
00:29:07.440 --> 00:29:12.939
Given the limited access to the Emacs server,
00:29:13.540 --> 00:29:16.719
I was comfortable enough to give bom.el a go
00:29:16.720 --> 00:29:18.799
to serve it on the public web.
00:29:18.800 --> 00:29:20.559
However, I immediately stopped
00:29:20.560 --> 00:29:22.879
after noticing how slow it is.
00:29:22.880 --> 00:29:24.719
It can take more than 30 seconds
00:29:24.720 --> 00:29:27.839
to load a page of weather forecast for a state.
00:29:27.840 --> 00:29:30.999
I am also not sure how many simultaneous connections
00:29:31.000 --> 00:29:32.379
it can handle.
00:29:32.380 --> 00:29:36.439
In any case, I think the package emacs-web-server
00:29:36.440 --> 00:29:40.419
could do with some performance enhancement.
NOTE Firefox with emacs for extensions
00:29:40.420 --> 00:29:43.999
Right. Because of the time constraints,
00:29:44.000 --> 00:29:45.759
I will briefly touch one final idea,
00:29:45.760 --> 00:29:50.320
which is to use Emacs as a Firefox browser extension.
00:29:50.420 --> 00:29:52.800
We already have org-protocol,
00:29:52.900 --> 00:29:54.439
which allows Firefox to communicate
00:29:54.440 --> 00:29:55.919
with a running Emacs server
00:29:55.920 --> 00:29:59.779
by sending an org-protocol URL to the latter.
00:29:59.780 --> 00:30:03.159
It can be used not just for capturing or storing links,
00:30:03.160 --> 00:30:10.119
but to execute arbitrary code on any component of the URL.
00:30:10.120 --> 00:30:11.679
However, it is fire and forget,
00:30:11.680 --> 00:30:16.479
and Emacs cannot tell Firefox what to do.
00:30:16.480 --> 00:30:17.919
There may be a length restriction, too.
00:30:17.920 --> 00:30:20.399
For example, Firefox may not be able to send back
00:30:20.400 --> 00:30:22.419
the whole DOM.
00:30:22.420 --> 00:30:26.219
This claim needs to be verified, though.
00:30:26.220 --> 00:30:30.019
Native messaging is one solution to this problem.
00:30:30.020 --> 00:30:31.639
It is a two-way communication channel
00:30:31.640 --> 00:30:35.319
between a Firefox web extension and a local system process
00:30:35.320 --> 00:30:37.839
started by the web extension.
00:30:37.840 --> 00:30:40.399
The process could be an Emacs server,
00:30:40.400 --> 00:30:42.399
which would make Emacs effectively
00:30:42.400 --> 00:30:48.679
a Firefox web browser extension.
00:30:48.680 --> 00:30:51.999
In this case, Elisp would be the main extension language,
00:30:52.000 --> 00:30:53.619
rather than JavaScript.
00:30:53.620 --> 00:30:56.159
However, JavaScript is still needed at the Firefox end
00:30:56.160 --> 00:30:59.220
of the communication channel.
00:30:59.320 --> 00:31:01.159
As a simple example of this idea,
00:31:01.160 --> 00:31:04.439
Firefox could ask Emacs to redirect a URL
00:31:04.440 --> 00:31:08.319
by removing tracking and using alternative frontend, etc.
00:31:08.320 --> 00:31:12.479
However, I was not able to implement this
00:31:12.480 --> 00:31:14.279
due to some tricky business
00:31:14.280 --> 00:31:15.639
with enforcing synchronicity
00:31:15.640 --> 00:31:17.119
that allows the web extension
00:31:17.120 --> 00:31:20.199
to wait for responses from Emacs.
00:31:20.200 --> 00:31:25.359
Some further work, I suppose.
NOTE Thank you
00:31:25.360 --> 00:31:28.154
That concludes my talk.
00:31:28.254 --> 00:31:31.440
Thank you for your attention.
