diff --git a/blog/2018-09-15-isomorphic-apps/_article.md b/blog/2018-09-15-isomorphic-apps/_article.md new file mode 100644 index 0000000..abc0dcb --- /dev/null +++ b/blog/2018-09-15-isomorphic-apps/_article.md @@ -0,0 +1,294 @@ +--- +layout: post +title: "Isomorphic Desktop Apps with Rust" +description: "Electron + WASM = ☣" +category: +tags: [rust, javascript, webassembly] +--- + +Forgive me, but this is going to be a bit of a schizophrenic post. I both despise Javascript and the +modern ECMAScript ecosystem, and I'm stunned by its success doing some really cool things. It's +[this duality](https://www.destroyallsoftware.com/talks/the-birth-and-death-of-javascript) that's +led me to a couple of (very) late nights over the past weeks trying to reconcile myself as I +bootstrap a simple desktop application. + +See, as much as +[Webassembly isn't trying to replace Javascript](https://webassembly.org/docs/faq/#is-webassembly-trying-to-replace-javascript), +**I want Javascript gone**. There are plenty of people who don't share my views, and they are +probably nicer and more fun at parties. But I cringe every time "Webpack" is mentioned, and I think +it's hilarious that the +[language specification](https://ecma-international.org/publications/standards/Ecma-402.htm) +dramatically outpaces anyone's +[actual implementation](https://kangax.github.io/compat-table/es2016plus/). The answer to this +conundrum is of course to recompile code from newer versions of the language to older versions _of +the same language_ before running. At least [Babel] is a nice tongue-in-cheek reference. + +Yet for as much hate as [Electron] receives, it does a stunningly good job at solving a really hard +problem: _how the hell do I put a button on the screen and react when the user clicks it_? GUI +programming is hard, straight up. But if browsers are already able to run everywhere, why don't we +take advantage of someone else solving the hard problems for us? I don't like that I have to use +Javascript for it, but I really don't feel inclined to whip out good ol' [wxWidgets]. + +Now there are other native solutions ([libui-rs], [conrod], [oh hey wxWdidgets again!][wxrust]), but +those also have their own issues with distribution, styling, etc. With Electron, I can +`yarn create electron-app my-app` and just get going, knowing that packaging/upgrades/etc. are built +in. + +My question is: given recent innovations with WASM, _are we Electron yet_? + +No, not really. + +Instead, **what would it take to get to a point where we can skip Javascript in Electron apps?** + +# Setting the Stage + +Truth is, WASM/Webassembly is a pretty new technology and I'm a total beginner in this area. There +may already be solutions to the issues I discuss, but I'm totally unaware of them, so I'm going to +try and organize what I did manage to discover. + +I should also mention that the content and things I'm talking about here are not intended to be +prescriptive, but more "if someone else is interested, what do we already know doesn't work?" _I +expect everything in this post to be obsolete within two months._ Even over the course of writing +this, [a separate blog post](https://mnt.io/2018/08/28/from-rust-to-beyond-the-asm-js-galaxy/) had +to be modified because [upstream changes](https://github.com/WebAssembly/binaryen/pull/1642) broke a +[Rust tool](https://github.com/rustwasm/wasm-bindgen/pull/787) the post tried to use. The post +ultimately +[got updated](https://mnt.io/2018/08/28/from-rust-to-beyond-the-asm-js-galaxy/#comment-477), **but +all this happened within the span of a week.** Things are moving quickly. + +I'll also note that we're going to skip [asm.js] and [emscripten]. Truth be told, I couldn't get +either of these to output anything, and so I'm just going to say +[here be dragons.](https://en.wikipedia.org/wiki/Here_be_dragons) Everything I'm discussing here +uses the `wasm32-unknown-unknown` target. + +The code that I _did_ get running is available +[over here](https://github.com/speice-io/isomorphic-rust). Feel free to use it as a starting point, +but I'm mostly including the link as a reference for the things that were attempted. + +# An Example Running Application + +So, I did _technically_ get a running application: + +![Electron app using WASM](/assets/images/2018-09-15-electron-percy-wasm.png) + +...which you can also try out if you want: + +```sh +git clone https://github.com/speice-io/isomorphic-rust.git +cd isomorphic_rust/percy +yarn install && yarn start +``` + +...but I wouldn't really call it a "high quality" starting point to base future work on. It's mostly +there to prove this is possible in the first place. And that's something to be proud of! There's a +huge amount of engineering that went into showing a window with the text "It's alive!". + +There's also a lot of usability issues that prevent me from recommending anyone try Electron and +WASM apps at the moment, and I think that's the more important thing to discuss. + +# Issue the First: Complicated Toolchains + +I quickly established that [wasm-bindgen] was necessary to "link" my Rust code to Javascript. At +that point you've got an Electron app that starts an HTML page which ultimately fetches your WASM +blob. To keep things simple, the goal was to package everything using [webpack] so that I could just +load a `bundle.js` file on the page. That decision was to be the last thing that kinda worked in +this process. + +The first issue +[I ran into](https://www.reddit.com/r/rust/comments/98lpun/unable_to_load_wasm_for_electron_application/) +while attempting to bundle everything via `webpack` is a detail in the WASM spec: + +> This function accepts a Response object, or a promise for one, and ... **[if > it] does not match +> the `application/wasm` MIME type**, the returned promise will be rejected with a TypeError; +> +> [WebAssembly - Additional Web Embedding API](https://webassembly.org/docs/web/#additional-web-embedding-api) + +Specifically, if you try and load a WASM blob without the MIME type set, you'll get an error. On the +web this isn't a huge issue, as the server can set MIME types when delivering the blob. With +Electron, you're resolving things with a `file://` URL and thus can't control the MIME type: + +![TypeError: Incorrect response MIME type. Expected 'application/wasm'.](/assets/images/2018-09-15-incorrect-MIME-type.png) + +There are a couple of solutions depending on how far into the deep end you care to venture: + +- Embed a static file server in your Electron application +- Use a [custom protocol](https://electronjs.org/docs/api/protocol) and custom protocol handler +- Host your WASM blob on a website that you resolve at runtime + +But all these are pretty bad solutions and defeat the purpose of using WASM in the first place. +Instead, my workaround was to +[open a PR with `webpack`](https://github.com/webpack/webpack/issues/7918) and use regex to remove +calls to `instantiateStreaming` in the +[build script](https://github.com/speice-io/isomorphic-rust/blob/master/percy/build.sh#L21-L25): + +```sh +cargo +nightly build --target=wasm32-unknown-unknown && \ + wasm-bindgen "$WASM_DIR/debug/$WASM_NAME.wasm" --out-dir "$APP_DIR" --no-typescript && \ + # Have to use --mode=development so we can patch out the call to instantiateStreaming + "$DIR/node_modules/webpack-cli/bin/cli.js" --mode=development "$APP_DIR/app_loader.js" -o "$APP_DIR/bundle.js" && \ + sed -i 's/.*instantiateStreaming.*//g' "$APP_DIR/bundle.js" +``` + +Once that lands, the +[build process](https://github.com/speice-io/isomorphic-rust/blob/master/percy_patched_webpack/build.sh#L24-L27) +becomes much simpler: + +```sh + +cargo +nightly build --target=wasm32-unknown-unknown && \ + wasm-bindgen "$WASM_DIR/debug/$WASM_NAME.wasm" --out-dir "$APP_DIR" --no-typescript && \ + "$DIR/node_modules/webpack-cli/bin/cli.js" --mode=production "$APP_DIR/app_loader.js" -o "$APP_DIR/bundle.js" +``` + +But we're not done yet! After we compile Rust into WASM and link WASM to Javascript (via +`wasm-bindgen` and `webpack`), we still have to make an Electron app. For this purpose I used a +starter app from [Electron Forge], and then a +[`prestart` script](https://github.com/speice-io/isomorphic-rust/blob/master/percy/package.json#L8) +to actually handle starting the application. + +The +[final toolchain](https://github.com/speice-io/isomorphic-rust/blob/master/percy/package.json#L8) +looks something like this: + +- `yarn start` triggers the `prestart` script +- `prestart` checks for missing tools (`wasm-bindgen-cli`, etc.) and then: + - Uses `cargo` to compile the Rust code into WASM + - Uses `wasm-bindgen` to link the WASM blob into a Javascript file with exported symbols + - Uses `webpack` to bundle the page start script with the Javascript we just generated + - Uses `babel` under the hood to compile the `wasm-bindgen` code down from ES6 into something + browser-compatible +- The `start` script runs an Electron Forge handler to do some sanity checks +- Electron actually starts + +...which is complicated. I think more work needs to be done to either build a high-quality starter +app that can manage these steps, or another tool that "just handles" the complexity of linking a +compiled WASM file into something the Electron browser can run. + +# Issue the Second: WASM tools in Rust + +For as much as I didn't enjoy the Javascript tooling needed to interface with Rust, the Rust-only +bits aren't any better at the moment. I get it, a lot of projects are just starting off, and that +leads to a fragmented ecosystem. Here's what I can recommend as a starting point: + +Don't check in your `Cargo.lock` files to version control. If there's a disagreement between the +version of `wasm-bindgen-cli` you have installed and the `wasm-bindgen` you're compiling with in +`Cargo.lock`, you get a nasty error: + +``` +it looks like the Rust project used to create this wasm file was linked against +a different version of wasm-bindgen than this binary: + +rust wasm file: 0.2.21 + this binary: 0.2.17 + +Currently the bindgen format is unstable enough that these two version must +exactly match, so it's required that these two version are kept in sync by +either updating the wasm-bindgen dependency or this binary. +``` + +Not that I ever managed to run into this myself (_coughs nervously_). + +There are two projects attempting to be "application frameworks": [percy] and [yew]. Between those, +I managed to get [two](https://github.com/speice-io/isomorphic-rust/tree/master/percy) +[examples](https://github.com/speice-io/isomorphic-rust/tree/master/percy_patched_webpack) running +using `percy`, but was unable to get an +[example](https://github.com/speice-io/isomorphic-rust/tree/master/yew) running with `yew` because +of issues with "missing modules" during the `webpack` step: + +```sh +ERROR in ./dist/electron_yew_wasm_bg.wasm +Module not found: Error: Can't resolve 'env' in '/home/bspeice/Development/isomorphic_rust/yew/dist' + @ ./dist/electron_yew_wasm_bg.wasm + @ ./dist/electron_yew_wasm.js + @ ./dist/app.js + @ ./dist/app_loader.js +``` + +If you want to work with the browser APIs directly, your choices are [percy-webapis] or [stdweb] (or +eventually [web-sys]). See above for my `percy` examples, but when I tried +[an example with `stdweb`](https://github.com/speice-io/isomorphic-rust/tree/master/stdweb), I was +unable to get it running: + +```sh +ERROR in ./dist/stdweb_electron_bg.wasm +Module not found: Error: Can't resolve 'env' in '/home/bspeice/Development/isomorphic_rust/stdweb/dist' + @ ./dist/stdweb_electron_bg.wasm + @ ./dist/stdweb_electron.js + @ ./dist/app_loader.js +``` + +At this point I'm pretty convinced that `stdweb` is causing issues for `yew` as well, but can't +prove it. + +I did also get a [minimal example](https://github.com/speice-io/isomorphic-rust/tree/master/minimal) +running that doesn't depend on any tools besides `wasm-bindgen`. However, it requires manually +writing "`extern C`" blocks for everything you need from the browser. Es no bueno. + +Finally, from a tools and platform view, there are two up-and-coming packages that should be +mentioned: [js-sys] and [web-sys]. Their purpose is to be fundamental building blocks that exposes +the browser's APIs to Rust. If you're interested in building an app framework from scratch, these +should give you the most flexibility. I didn't touch either in my research, though I expect them to +be essential long-term. + +So there's a lot in play from the Rust side of things, and it's just going to take some time to +figure out what works and what doesn't. + +# Issue the Third: Known Unknowns + +Alright, so after I managed to get an application started, I stopped there. It was a good deal of +effort to chain together even a proof of concept, and at this point I'd rather learn [Typescript] +than keep trying to maintain an incredibly brittle pipeline. Blasphemy, I know... + +The important point I want to make is that there's a lot unknown about how any of this holds up +outside proofs of concept. Things I didn't attempt: + +- Testing +- Packaging +- Updates +- Literally anything related to why I wanted to use Electron in the first place + +# What it Would Take + +Much as I don't like Javascript, the tools are too shaky for me to recommend mixing Electron and +WASM at the moment. There's a lot of innovation happening, so who knows? Someone might have an +application in production a couple months from now. But at the moment, I'm personally going to stay +away. + +Let's finish with a wishlist then - here are the things that I think need to happen before +Electron/WASM/Rust can become a thing: + +- Webpack still needs some updates. The necessary work is in progress, but hasn't landed yet + ([#7983](https://github.com/webpack/webpack/pull/7983)) +- Browser API libraries (`web-sys` and `stdweb`) need to make sure they can support running in + Electron (see module error above) +- Projects need to stabilize. There's talk of `stdweb` being turned into a Rust API + [on top of web-sys](https://github.com/rustwasm/team/issues/226#issuecomment-418475778), and percy + [moving to web-sys](https://github.com/chinedufn/percy/issues/24), both of which are big changes +- `wasm-bindgen` is great, but still in the "move fast and break things" phase +- A good "boilerplate" app would dramatically simplify the start-up costs; + [electron-react-boilerplate](https://github.com/chentsulin/electron-react-boilerplate) comes to + mind as a good project to imitate +- More blog posts/contributors! I think Electron + Rust could be cool, but I have no idea what I'm + doing + +[wxwidgets]: https://wxwidgets.org/ +[libui-rs]: https://github.com/LeoTindall/libui-rs/ +[electron]: https://electronjs.org/ +[babel]: https://babeljs.io/ +[wxrust]: https://github.com/kenz-gelsoft/wxRust +[wasm-bindgen]: https://github.com/rustwasm/wasm-bindgen +[js-sys]: https://crates.io/crates/js-sys +[percy-webapis]: https://crates.io/crates/percy-webapis +[stdweb]: https://crates.io/crates/stdweb +[web-sys]: https://crates.io/crates/web-sys +[percy]: https://chinedufn.github.io/percy/ +[virtual-dom-rs]: https://crates.io/crates/virtual-dom-rs +[yew]: https://github.com/DenisKolodin/yew +[react]: https://reactjs.org/ +[elm]: http://elm-lang.org/ +[asm.js]: http://asmjs.org/ +[emscripten]: https://kripken.github.io/emscripten-site/ +[typescript]: https://www.typescriptlang.org/ +[electron forge]: https://electronforge.io/ +[conrod]: https://github.com/PistonDevelopers/conrod +[webpack]: https://webpack.js.org/ diff --git a/blog/2018-09-15-isomorphic-apps/electron-percy-wasm.png b/blog/2018-09-15-isomorphic-apps/electron-percy-wasm.png new file mode 100644 index 0000000..0abf67f Binary files /dev/null and b/blog/2018-09-15-isomorphic-apps/electron-percy-wasm.png differ diff --git a/blog/2018-09-15-isomorphic-apps/incorrect-MIME-type.png b/blog/2018-09-15-isomorphic-apps/incorrect-MIME-type.png new file mode 100644 index 0000000..f1c297e Binary files /dev/null and b/blog/2018-09-15-isomorphic-apps/incorrect-MIME-type.png differ diff --git a/blog/2018-09-15-isomorphic-apps/index.mdx b/blog/2018-09-15-isomorphic-apps/index.mdx new file mode 100644 index 0000000..48ee33e --- /dev/null +++ b/blog/2018-09-15-isomorphic-apps/index.mdx @@ -0,0 +1,295 @@ +--- +slug: 2018/09/isomorphic-apps +title: "Isomorphic desktop apps with Rust" +date: 2018-09-15 12:00:00 +authors: [bspeice] +tags: [] +--- + +I both despise Javascript and am stunned by its success doing some really cool things. It's +[this duality](https://www.destroyallsoftware.com/talks/the-birth-and-death-of-javascript) that's +led me to a couple of (very) late nights over the past weeks trying to reconcile myself as I +bootstrap a simple desktop application. + + + +See, as much as +[Webassembly isn't trying to replace Javascript](https://webassembly.org/docs/faq/#is-webassembly-trying-to-replace-javascript), +**I want Javascript gone**. There are plenty of people who don't share my views, and they are +probably nicer and more fun at parties. But I cringe every time "Webpack" is mentioned, and I think +it's hilarious that the +[language specification](https://ecma-international.org/publications/standards/Ecma-402.htm) +dramatically outpaces anyone's +[actual implementation](https://kangax.github.io/compat-table/es2016plus/). The answer to this +conundrum is of course to recompile code from newer versions of the language to older versions _of +the same language_ before running. At least [Babel] is a nice tongue-in-cheek reference. + +Yet for as much hate as [Electron] receives, it does a stunningly good job at solving a really hard +problem: _how the hell do I put a button on the screen and react when the user clicks it_? GUI +programming is hard, straight up. But if browsers are already able to run everywhere, why don't we +take advantage of someone else solving the hard problems for us? I don't like that I have to use +Javascript for it, but I really don't feel inclined to whip out good ol' [wxWidgets]. + +Now there are other native solutions ([libui-rs], [conrod], [oh hey wxWdidgets again!][wxrust]), but +those also have their own issues with distribution, styling, etc. With Electron, I can +`yarn create electron-app my-app` and just get going, knowing that packaging/upgrades/etc. are built +in. + +My question is: given recent innovations with WASM, _are we Electron yet_? + +No, not really. + +Instead, **what would it take to get to a point where we can skip Javascript in Electron apps?** + +# Setting the Stage + +Truth is, WASM/Webassembly is a pretty new technology and I'm a total beginner in this area. There +may already be solutions to the issues I discuss, but I'm totally unaware of them, so I'm going to +try and organize what I did manage to discover. + +I should also mention that the content and things I'm talking about here are not intended to be +prescriptive, but more "if someone else is interested, what do we already know doesn't work?" _I +expect everything in this post to be obsolete within two months._ Even over the course of writing +this, [a separate blog post](https://mnt.io/2018/08/28/from-rust-to-beyond-the-asm-js-galaxy/) had +to be modified because [upstream changes](https://github.com/WebAssembly/binaryen/pull/1642) broke a +[Rust tool](https://github.com/rustwasm/wasm-bindgen/pull/787) the post tried to use. The post +ultimately +[got updated](https://mnt.io/2018/08/28/from-rust-to-beyond-the-asm-js-galaxy/#comment-477), **but +all this happened within the span of a week.** Things are moving quickly. + +I'll also note that we're going to skip [asm.js] and [emscripten]. Truth be told, I couldn't get +either of these to output anything, and so I'm just going to say +[here be dragons.](https://en.wikipedia.org/wiki/Here_be_dragons) Everything I'm discussing here +uses the `wasm32-unknown-unknown` target. + +The code that I _did_ get running is available +[over here](https://github.com/speice-io/isomorphic-rust). Feel free to use it as a starting point, +but I'm mostly including the link as a reference for the things that were attempted. + +# An Example Running Application + +So, I did _technically_ get a running application: + +![Electron app using WASM](./electron-percy-wasm.png) + +...which you can also try out if you want: + +```sh +git clone https://github.com/speice-io/isomorphic-rust.git +cd isomorphic_rust/percy +yarn install && yarn start +``` + +...but I wouldn't really call it a "high quality" starting point to base future work on. It's mostly +there to prove this is possible in the first place. And that's something to be proud of! There's a +huge amount of engineering that went into showing a window with the text "It's alive!". + +There's also a lot of usability issues that prevent me from recommending anyone try Electron and +WASM apps at the moment, and I think that's the more important thing to discuss. + +# Issue the First: Complicated Toolchains + +I quickly established that [wasm-bindgen] was necessary to "link" my Rust code to Javascript. At +that point you've got an Electron app that starts an HTML page which ultimately fetches your WASM +blob. To keep things simple, the goal was to package everything using [webpack] so that I could just +load a `bundle.js` file on the page. That decision was to be the last thing that kinda worked in +this process. + +The first issue +[I ran into](https://www.reddit.com/r/rust/comments/98lpun/unable_to_load_wasm_for_electron_application/) +while attempting to bundle everything via `webpack` is a detail in the WASM spec: + +> This function accepts a Response object, or a promise for one, and ... **[if > it] does not match +> the `application/wasm` MIME type**, the returned promise will be rejected with a TypeError; +> +> [WebAssembly - Additional Web Embedding API](https://webassembly.org/docs/web/#additional-web-embedding-api) + +Specifically, if you try and load a WASM blob without the MIME type set, you'll get an error. On the +web this isn't a huge issue, as the server can set MIME types when delivering the blob. With +Electron, you're resolving things with a `file://` URL and thus can't control the MIME type: + +![TypeError: Incorrect response MIME type. Expected 'application/wasm'.](./incorrect-MIME-type.png) + +There are a couple of solutions depending on how far into the deep end you care to venture: + +- Embed a static file server in your Electron application +- Use a [custom protocol](https://electronjs.org/docs/api/protocol) and custom protocol handler +- Host your WASM blob on a website that you resolve at runtime + +But all these are pretty bad solutions and defeat the purpose of using WASM in the first place. +Instead, my workaround was to +[open a PR with `webpack`](https://github.com/webpack/webpack/issues/7918) and use regex to remove +calls to `instantiateStreaming` in the +[build script](https://github.com/speice-io/isomorphic-rust/blob/master/percy/build.sh#L21-L25): + +```sh +cargo +nightly build --target=wasm32-unknown-unknown && \ + wasm-bindgen "$WASM_DIR/debug/$WASM_NAME.wasm" --out-dir "$APP_DIR" --no-typescript && \ + # Have to use --mode=development so we can patch out the call to instantiateStreaming + "$DIR/node_modules/webpack-cli/bin/cli.js" --mode=development "$APP_DIR/app_loader.js" -o "$APP_DIR/bundle.js" && \ + sed -i 's/.*instantiateStreaming.*//g' "$APP_DIR/bundle.js" +``` + +Once that lands, the +[build process](https://github.com/speice-io/isomorphic-rust/blob/master/percy_patched_webpack/build.sh#L24-L27) +becomes much simpler: + +```sh + +cargo +nightly build --target=wasm32-unknown-unknown && \ + wasm-bindgen "$WASM_DIR/debug/$WASM_NAME.wasm" --out-dir "$APP_DIR" --no-typescript && \ + "$DIR/node_modules/webpack-cli/bin/cli.js" --mode=production "$APP_DIR/app_loader.js" -o "$APP_DIR/bundle.js" +``` + +But we're not done yet! After we compile Rust into WASM and link WASM to Javascript (via +`wasm-bindgen` and `webpack`), we still have to make an Electron app. For this purpose I used a +starter app from [Electron Forge], and then a +[`prestart` script](https://github.com/speice-io/isomorphic-rust/blob/master/percy/package.json#L8) +to actually handle starting the application. + +The +[final toolchain](https://github.com/speice-io/isomorphic-rust/blob/master/percy/package.json#L8) +looks something like this: + +- `yarn start` triggers the `prestart` script +- `prestart` checks for missing tools (`wasm-bindgen-cli`, etc.) and then: + - Uses `cargo` to compile the Rust code into WASM + - Uses `wasm-bindgen` to link the WASM blob into a Javascript file with exported symbols + - Uses `webpack` to bundle the page start script with the Javascript we just generated + - Uses `babel` under the hood to compile the `wasm-bindgen` code down from ES6 into something + browser-compatible +- The `start` script runs an Electron Forge handler to do some sanity checks +- Electron actually starts + +...which is complicated. I think more work needs to be done to either build a high-quality starter +app that can manage these steps, or another tool that "just handles" the complexity of linking a +compiled WASM file into something the Electron browser can run. + +# Issue the Second: WASM tools in Rust + +For as much as I didn't enjoy the Javascript tooling needed to interface with Rust, the Rust-only +bits aren't any better at the moment. I get it, a lot of projects are just starting off, and that +leads to a fragmented ecosystem. Here's what I can recommend as a starting point: + +Don't check in your `Cargo.lock` files to version control. If there's a disagreement between the +version of `wasm-bindgen-cli` you have installed and the `wasm-bindgen` you're compiling with in +`Cargo.lock`, you get a nasty error: + +``` +it looks like the Rust project used to create this wasm file was linked against +a different version of wasm-bindgen than this binary: + +rust wasm file: 0.2.21 + this binary: 0.2.17 + +Currently the bindgen format is unstable enough that these two version must +exactly match, so it's required that these two version are kept in sync by +either updating the wasm-bindgen dependency or this binary. +``` + +Not that I ever managed to run into this myself (_coughs nervously_). + +There are two projects attempting to be "application frameworks": [percy] and [yew]. Between those, +I managed to get [two](https://github.com/speice-io/isomorphic-rust/tree/master/percy) +[examples](https://github.com/speice-io/isomorphic-rust/tree/master/percy_patched_webpack) running +using `percy`, but was unable to get an +[example](https://github.com/speice-io/isomorphic-rust/tree/master/yew) running with `yew` because +of issues with "missing modules" during the `webpack` step: + +```sh +ERROR in ./dist/electron_yew_wasm_bg.wasm +Module not found: Error: Can't resolve 'env' in '/home/bspeice/Development/isomorphic_rust/yew/dist' + @ ./dist/electron_yew_wasm_bg.wasm + @ ./dist/electron_yew_wasm.js + @ ./dist/app.js + @ ./dist/app_loader.js +``` + +If you want to work with the browser APIs directly, your choices are [percy-webapis] or [stdweb] (or +eventually [web-sys]). See above for my `percy` examples, but when I tried +[an example with `stdweb`](https://github.com/speice-io/isomorphic-rust/tree/master/stdweb), I was +unable to get it running: + +```sh +ERROR in ./dist/stdweb_electron_bg.wasm +Module not found: Error: Can't resolve 'env' in '/home/bspeice/Development/isomorphic_rust/stdweb/dist' + @ ./dist/stdweb_electron_bg.wasm + @ ./dist/stdweb_electron.js + @ ./dist/app_loader.js +``` + +At this point I'm pretty convinced that `stdweb` is causing issues for `yew` as well, but can't +prove it. + +I did also get a [minimal example](https://github.com/speice-io/isomorphic-rust/tree/master/minimal) +running that doesn't depend on any tools besides `wasm-bindgen`. However, it requires manually +writing "`extern C`" blocks for everything you need from the browser. Es no bueno. + +Finally, from a tools and platform view, there are two up-and-coming packages that should be +mentioned: [js-sys] and [web-sys]. Their purpose is to be fundamental building blocks that exposes +the browser's APIs to Rust. If you're interested in building an app framework from scratch, these +should give you the most flexibility. I didn't touch either in my research, though I expect them to +be essential long-term. + +So there's a lot in play from the Rust side of things, and it's just going to take some time to +figure out what works and what doesn't. + +# Issue the Third: Known Unknowns + +Alright, so after I managed to get an application started, I stopped there. It was a good deal of +effort to chain together even a proof of concept, and at this point I'd rather learn [Typescript] +than keep trying to maintain an incredibly brittle pipeline. Blasphemy, I know... + +The important point I want to make is that there's a lot unknown about how any of this holds up +outside proofs of concept. Things I didn't attempt: + +- Testing +- Packaging +- Updates +- Literally anything related to why I wanted to use Electron in the first place + +# What it Would Take + +Much as I don't like Javascript, the tools are too shaky for me to recommend mixing Electron and +WASM at the moment. There's a lot of innovation happening, so who knows? Someone might have an +application in production a couple months from now. But at the moment, I'm personally going to stay +away. + +Let's finish with a wishlist then - here are the things that I think need to happen before +Electron/WASM/Rust can become a thing: + +- Webpack still needs some updates. The necessary work is in progress, but hasn't landed yet + ([#7983](https://github.com/webpack/webpack/pull/7983)) +- Browser API libraries (`web-sys` and `stdweb`) need to make sure they can support running in + Electron (see module error above) +- Projects need to stabilize. There's talk of `stdweb` being turned into a Rust API + [on top of web-sys](https://github.com/rustwasm/team/issues/226#issuecomment-418475778), and percy + [moving to web-sys](https://github.com/chinedufn/percy/issues/24), both of which are big changes +- `wasm-bindgen` is great, but still in the "move fast and break things" phase +- A good "boilerplate" app would dramatically simplify the start-up costs; + [electron-react-boilerplate](https://github.com/chentsulin/electron-react-boilerplate) comes to + mind as a good project to imitate +- More blog posts/contributors! I think Electron + Rust could be cool, but I have no idea what I'm + doing + +[wxwidgets]: https://wxwidgets.org/ +[libui-rs]: https://github.com/LeoTindall/libui-rs/ +[electron]: https://electronjs.org/ +[babel]: https://babeljs.io/ +[wxrust]: https://github.com/kenz-gelsoft/wxRust +[wasm-bindgen]: https://github.com/rustwasm/wasm-bindgen +[js-sys]: https://crates.io/crates/js-sys +[percy-webapis]: https://crates.io/crates/percy-webapis +[stdweb]: https://crates.io/crates/stdweb +[web-sys]: https://crates.io/crates/web-sys +[percy]: https://chinedufn.github.io/percy/ +[virtual-dom-rs]: https://crates.io/crates/virtual-dom-rs +[yew]: https://github.com/DenisKolodin/yew +[react]: https://reactjs.org/ +[elm]: http://elm-lang.org/ +[asm.js]: http://asmjs.org/ +[emscripten]: https://kripken.github.io/emscripten-site/ +[typescript]: https://www.typescriptlang.org/ +[electron forge]: https://electronforge.io/ +[conrod]: https://github.com/PistonDevelopers/conrod +[webpack]: https://webpack.js.org/ diff --git a/docusaurus.config.ts b/docusaurus.config.ts index 1f21c19..9667860 100644 --- a/docusaurus.config.ts +++ b/docusaurus.config.ts @@ -80,7 +80,7 @@ const config: Config = { prism: { theme: prismThemes.oneLight, darkTheme: prismThemes.oneDark, - additionalLanguages: ['java', 'julia', 'nasm'] + additionalLanguages: ['bash', 'java', 'julia', 'nasm'] }, } satisfies Preset.ThemeConfig, plugins: [require.resolve('docusaurus-lunr-search')],