webpack dynamic import not working

The following methods are supported by webpack: import Statically import the export s of another module. You may want to look into output.publicPath to setup to correct URL. Can you write oxidation states with negative Roman numerals? | 18 modules Notice how the chunk depends on the animal name. Adding Hashes to Filenames - SurviveJS Now I have to do some refactoring in my app, but thats not a problem. *$ namespace object:43**. Are the Webpack Magic Comments Understanding React dynamic imports for faster websites - OpenReplay Blog Theoretically Correct vs Practical Notation, How do you get out of a corner when plotting yourself into a corner, How to handle a hobby that makes income in US, Replacing broken pins/legs on a DIP IC package, Surly Straggler vs. other types of steel frames. Lets suppose you have an app that has different behavior and visuals in some features for mobile to desktop. What is the expected behavior? Webpack 3, Dynamic Imports, Code Splitting, and Long Term Caching Made [37] ./sources/anytime.js 2.12 KiB {0} [built] When webpack finds a dynamic import, it will assume that code should be code split and lazy loaded. It's totally understandable that webpack is a bundler and it should not take care of loading script from another domain. Now it works. Entrypoint anytime = anytime.css anytime.bundle.js Vue.js dynamic image src with webpack require() not working [10] ./sources/views/admin/subscriptions.js 9.79 KiB {0} [built] Now here's the part that errors on build. [41] ./sources/locales sync ^\.\/.$ 181 bytes {0} [built] This argument calls a dynamic import and returns a promise. We hand-pick interesting articles related to front-end development. The compiler will ensure that the dependency is available in the output bundle. You do not need to add curly brackets. If you want to follow along, you can find a StackBlitz demo here(it's safe to run npm run build first). I cant thank you enough maksim! I am trying to setup dynamic svg imports since my app uses many icons and I don't want to impact startup time to load all icons i.e. Flask api hosted as a docker container works with localhost:5000 but not with 172.17..2:5000; Python Flask heroku application error; Failed to compute cache key: "/films" not found: not found? import('http://example.com/some-module/some-module.bundle.js').then(module => console.log(module.default)); How can I load an external resource from an external url? Not the answer you're looking for? Although it worked with webpack@3. Redoing the align environment with a specific formatting, How to handle a hobby that makes income in US, Minimising the environmental effects of my dyson brain. // Requesting the module that should already be available. webpack version: 4.25.1 my-custom-comp.vue, I have my-custom-comp package installed in my app, and add package path to resolve.modules: Refresh the page, check Medium 's site status, or find something interesting to read. TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for ./webpack.config.ts, Examples of how to get and use webpack logger in loaders and plugins, __webpack_public_path__ (webpack-specific), __webpack_chunk_load__ (webpack-specific), __webpack_get_script_filename__ (webpack-specific), __non_webpack_require__ (webpack-specific), __webpack_exports_info__ (webpack-specific), __webpack_is_included__ (webpack-specific), No CommonJS allowed, for example, you can't use, File extensions are required when importing, e.g, you should use, File extensions are required when importing wasm file. // Here the user chooses the name of the file. It is crucial to have a (root) parent chunk because it contains the required logic to fetch and integrate other child chunks in the application. privacy statement. The text was updated successfully, but these errors were encountered: That part wraps the result in a namespace object as import() always returns a namespace object. Have a question about this project? If youre using HTTP2 is better to break the big bundles in smaller pieces. This can be verified in our example: after starting the server, try to require any of the modules present in the animals directory. You signed in with another tab or window. Check out the guide for more information on how webpackPreload works. Secure websites are necessary requirements. - Coco Jun 21, 2018 at 20:36 Already have this plugin installed, and it still does not work. *.js(loosely).In the upcoming sections we will explore what happens once these files have been figured. Using Webpack and the dynamic import structure it creates a promise that will retrieve the chunk at runtime and allow you to act on it at that point. There are no special prerequisites, apart from a basic understanding of how the import function behaves when its argument is static(i.e it creates a new chunk). There are four different methods (lazy, lazy-once, eager, weak). Basically, 9 indicates a simple ES module, case in which the module with the moduleId will be required. Node.js version: v14.4.0 What am I doing wrong? Bundling can be limited to a specific directory or set of files so that when you are using a dynamic expression - every module that could potentially be requested on an import() call is included. webpack --env.production true, Hash: 40911497abda454cf910 It's able to require modules without indicating they should be bundled into a chunk. eg: ./locale. All the following sections will be based on the same example where there is a directory called animals and inside there are files that correspond to animals: Each examples uses the import function like this: import('./animals/${fileName}.js'). Dynamic import seems to be the solution but Im not having any luck getting webpack to create the chunk files. It's used in conjunction with import() which takes over when user navigation triggers additional imports. Modules are reusable chunks of code built from your app's JavaScript, node_modules, images, and CSS styles, which are packaged to be easily used on your website. Here's the function which calls the dynamic import: Everything I have read says this is the way to set this up. to your account, __webpack_require__ is called with result of promise external when it's is loaded as dynamic import, which results with error React.lazy handles this promise and expects it to return a module that contains a default export React component. Then I started going through all of the plugins in the Babel configuration. Webpack importscripts - bmh.ristorantelaquiete.it This is only needed in rare cases for compatibility! How can I remove a specific item from an array in JavaScript? If I want to use the cat module, after clicking on the button, I should see a new request for the chunk which contains the module in question: As probably noticed, the console tells us that the chunk has been loaded, as well as the module it contains, namely the cat module. The same file structure is assumed: To learn more, see our tips on writing great answers. ECMAScript Asynchronicity - dynamic import | Blog Eleven Labs The unexpected impact of dynamic imports on tree shaking But what is the difference between prefetch and preload?. Let's first see the example which we'll use throughout this section: As you can see, the mode can be specified with the webpackMode: 'eager' magic comment. For instance: In the above map(which can be found in the dist/main.js file - the only generated file), it is known for sure that the cat module is used across the app. If you preorder a special airline meal (e.g. Already on GitHub? Dynamic Import from external URL will throw, v2 Addon Format (Embroider compatibility), Dynamic Import not working with variable path. If a hash has changed, the client is forced to download the asset again. How do I remove a property from a JavaScript object? Additional tools: None. Well, practically it isn't, because all those possible chunks are just files held on the server which are not sent to the browser unless the browser requires them(e.g when the import()'s path matches an existing file path). A curious software developer with a passion for solving problems and learning new things. When the user presses the button to load a module, the entire chunk will be requested over the network and when it is ready, the module requested by the user will be executed and retrieved. Successfully merging a pull request may close this issue. Update: If youre using Babel 7.5+ it already includes the dynamic import plugin for you ;). What happens in this example is that the user will type the name of an animal into the input and when the button is clicked, the chunk which corresponds to that name will be loaded. Asking for help, clarification, or responding to other answers. Using it asynchronously may not have the expected effect. Powered by Discourse, best viewed with JavaScript enabled, webix-hub/jet-demos/blob/master/webpack.config.js#L20, webix-hub/jet-demos/blob/master/sources/bundles.js#L18, loader: "babel-loader?" So, to make it work with webpack you need to first install the babel-plugin-syntax-dynamic-import . import() work. Currently, @babel/preset-env is unaware that using import () with Webpack relies on Promise internally. Technically, you could stop here and officially have done code splitting! Use require instead, e.g. Although it worked with webpack@3. Sign in to comment To do so, we can simply use, instead of webpackMode: eager the webpackPrefetch: true which makes the browser download the chunks after the parent bundle/chunk. And consider adding service workers with a good caching strategy. Best Guide on Dynamic Import in JavaScript for Importing Modules Dynamic Imports of JSON - DEV Community node --max_old_space_size=8000 scripts/start.js. // And here the chunk is loaded. rev2023.3.3.43278. Based on the default configuration, our initial expression ./animals/${fileName}.js will result in ./animals/. For now, we will focus on the import's argument. Find centralized, trusted content and collaborate around the technologies you use most. The following options are supported: webpackPrefetch: Tells the browser that the resource is probably needed for some navigation in the future. [11] ./sources/views/timeclock.js 2.92 KiB {0} [built] Refresh the page, check Medium 's site status, or find something interesting to read. The goal of CommonJS is to specify an ecosystem for JavaScript outside the browser. you can get around this by using that attribute as the src attribute in a script tag. A prefetched chunk starts after the parent chunk finish. [6] ./sources/views/admin/win_create_subsuser.js 3.24 KiB {0} [built] But it took approximately 10 minutes to load. The nature of simulating nature: A Q&A with IBM Quantum researcher Dr. Jamie We've added a "Necessary cookies only" option to the cookie consent popup. Ive setup my code according to the jet-demos example and still not having any luck with webpack generating the chunk file. Can you write oxidation states with negative Roman numerals? Also, if this one doesnt work, try to move the loaded file outside of views folder. [5] ./sources/views/admin/win_add_subsuser.js 3.19 KiB {0} [built] For a full list of these magic comments see the code below followed by an explanation of what these comments do. Environment Variables | webpack dynamic import for chunk in node_modules is not working as expected #10722 alexander-akait mentioned this issue Ability to force bundling of a module #11223 alexander-akait closed this as completed on Jul 24, 2020 Sign up for free to join this conversation on GitHub . Well occasionally send you account related emails. Lets now explore those strategies in greater detail. Any help would be greatly appreciated. Keep in mind that you will still probably need babel for other ES6+ features. In this case, having only a responsive design doesnt cover what you want, so you build a page renderer which loads and renders the page based on the user platform. If the current behavior is a bug, please provide the steps to reproduce. This is the same for core-js@2, except the imports paths are slightly different: --save-dev @babel/plugin-syntax-dynamic-import, --dev @babel/plugin-syntax-dynamic-import, babel --plugins @babel/plugin-syntax-dynamic-import script.js, Working with Webpack and @babel/preset-env. In the Lib project: Create an entry point file, say index.js, that exports all the custom React components like this: import {Button} from './button'; import {DatePicker} from . There is also an article named An in-depth perspective on webpack's bundling process in which concepts such as Modules and Chunks are explained, but it shouldn't affect the understanding of this article too much. Already have this plugin installed, and it still does not work. webpackChunkName: A name for the new chunk. *$/, any file */, /* optional, 'sync' | 'eager' | 'weak' | 'lazy' | 'lazy-once', default 'sync' */. The expected behavior is that no requests should appear in the Network panel and each existing module should be executed properly, as seen in the following image: Finally, here's a diagram to summarize this mode's behavior: The StackBlitz app for this section can be found here. @babel/plugin-syntax-dynamic-import Babel I'm trying to migrate my app to webpack 4. It's because I am using the presets in Babel; comments are on by default. You put it in like so: "syntax-dynamic-import". Dynamic SVG import in Preact + Vite - Stack Overflow Sorry for delay. The loader uses importScripts to dynamically load modules from within your web-worker and support cross-domain web workers. So the role of the map object from above is so keep track of modules which have a purpose(i.e if they are used at all) at all in the project. As far as the ./animals/${fileName}.js segment is concerned, each ${fileName} refers to a dynamic part and it will be replaced with /. Let's also try it in our example. How do you use a variable in a regular expression? The diagrams have been made with Excalidraw. webpackExclude: A regular expression that will be matched against during import resolution. True, even if were dynamic loading the components, this stills a pretty attached solution. Here's my test repository https://github.com/younabobo/webpack-dynamic-import-test, @younabobo @evilebottnawi At the same time, webpack is preventing this by throwing the Module not found error. My problem was closely related to #7417, @younabobo It is documented, we can't build module from x, it is runtime value and it is impossible to detect https://webpack.js.org/api/module-methods/#dynamic-expressions-in-import, @ufon You need this #11127, we will implement it for webpack@5. By default webpack import all files from views folder, which can conflict with code splitting. In this article we will learn about demistifying webpack's 'import' function: using dynamic arguments. This issue had no activity for at least half a year. Get the latest coverage of advanced web development straight into your inbox. Module Methods | webpack In this way, you only load the code that you need. Connect and share knowledge within a single location that is structured and easy to search. Let us help you. It's possible to enable magic comments for require as well, see module.parser.javascript.commonjsMagicComments for more. next/image component not working within a dynamic import in /app/ and It's subject to automatic issue closing if there is no activity in the next 15 days. Sign in By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Similar to require.resolve, but this won't pull the module into the bundle. I don't know if there's a cleaner way, but I've seen script.js used with success for the google maps api specifically. - jeron-diovis Feb 8, 2019 at 8:41 Add a comment 2 Answers Sorted by: 6 I was facing the same issue the fix was: @evilebottnawi Please look at this repo: https://github.com/Miaoxingren/webpack-issue-8934. The keyword here is statically. In this article we've learned that the import function can do much more than simply creating a chunk. 7 indicates a CommonJS module and in this case webpack needs to create a fake ES module from it.To see it in practice, you can open the last provided example and start the server. How Webpack Handles Dynamic Imports with Variable Paths Hopefully, at this point, things make more sense when it comes to using import with dynamic arguments. So, your initial bundle size will be smaller. By using weak imports, we're essentially telling webpack that the resources we want to use should already be prepared for retrieval. Connect and share knowledge within a single location that is structured and easy to search. The following is tested with Webpack 2, but should also work with v.1. In this situation, the cat.js file is a CommonJS module and the rest are ES modules: The StackBlitz app for this new example can be found here. Dynamic imports stopped working in Webpack v4. However, it does not necessarily guarantee that the cat module is available. If the module source contains a require that cannot be statically analyzed, critical dependencies warning is emitted. /* webpackChunkName: 'animal', webpackMode: 'eager' */, /* Working with modern JS you often see static imports for modules: import myLib from './myLib'; But dynamic imports aren't grabbed from the server until runtime. This looks like an obvious problem and with that many libraries out there, someone must have found a solution I guess. @ooflorent Is it possible to import the bundle from external url in webpack for e.g. const LazyComponent = lazy(() => import(packageOne)). Asset Size Chunks Chunk Names Webpack Dynamic Import Expression Not Working - Stack Overflow How can we prove that the supernatural or paranormal doesn't exist? // the chunk whose name corresponds to the animal name will be loaded. Thanks T. I guess I cannot 'dynamically' load/include only the component I need on a pre page basis, I'll have to manually include all available componests so if they are within the 'layout' object, then they will be available. To see an example of what that array would look like, you can open the StackBlitz app whose link can be found at the beginning of this section(or here) and run the npm run build script. NOTE: This plugin is included in @babel/preset-env, in ES2020. With this, it's also close to the lazy mode, as far as the lazy chunk goes. @sokra Could you be more specific? I got a folder with hundreds of SVGs in it. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Babel plugin to transpile import () to require.ensure, for Webpack. https://github.com/roblan/webpack-external-promise-import, __webpack_require__ should not be called on promise external result. Making statements based on opinion; back them up with references or personal experience. You can take a look into the descriptions in more detail here. Environments which do not have builtin support for Promise, like Internet Explorer, will require both the promise and iterator polyfills be added manually. Let's learn how to enable HTTPS on localhost for a PHP application on Apache by Dockerizing it. According to the document: I should upload dist files of my-custom-comp to cdn or copy dist files of my-custom-comp to app's assets folder? Would anyone have any ideas as to why webpack wouldnt create the chunk files? Webpack provides a method of templating the filenames using bracketed strings called substitutions. I solved it. So, is better to preload that small image chunks than add it to the bigger bundle/chunk right? Javascript is not recognizing a Flask variable; Jinja2 - Expressions concatenating issue; Recursion with WTForms and Jinja If you want to check the how-to make a lazy-loaded single page application (SPA) using the discussed dynamic import, you can check out two of my previous articles on this subject. Then, if you open the dist/main.js file, you can already notice the map we talked about earlier: Once again, this object follows this pattern: { filename: [moduleId, chunkId] }. Once the npm run build is run, the dist directory should have 2 files: main.js, which is the main chunk, and animal.js, which is the chunk in which all the modules corresponding to the files inside the animals/ directory reside. This way, all the file paths will be promptly available when your app loads the parent bundle/chunk. Dynamic import from node_modules is not working #8934 - GitHub webpack should generate code without second __webpack_require__ call: webpack should resolve dynamic import with { default: 42 }, Other relevant information: Since webpack 2.6.0, the placeholders [index] and [request] are supported within the given string to an incremented number or the actual resolved filename respectively. For example, import(`./locale/${language}.json`) will cause every .json file in the ./locale directory to be bundled into the new chunk. If youre using HTTPS is even worse! Already on GitHub? Do new devs get fired if they can't solve a certain bug? This Is Why fatfish in JavaScript in Plain English It's 2022, Please Don't Just Use "console.log" Anymore Jesse Langford in Better Programming Consolidate Your TypeScript Imports With index.ts Files Help Status Writers Blog privacy statement. However, if you try with any other module than cat, the same error will appear: This feature could be used to enforce modules to be loaded beforehand, so that you ensure that at a certain point the modules accessible. Because foo could potentially be any path to any file in your system or project. [9] ./sources/views/admin/dashboard.js 1.58 KiB {0} [built] If the name of the animal can't be found in the animals directory, an error will be thrown. Asking for help, clarification, or responding to other answers. /* webpackChunkName: 'animal', webpackMode: 'lazy-once' */, // Here the user types the name of the module, // Here that module is retrieved directly if possible, otherwise, /* webpackChunkName: 'animal', webpackMode: 'weak' */. The First line of the Readme of the repo: And this is what is causing all the trouble. Making statements based on opinion; back them up with references or personal experience. How do I check if an element is hidden in jQuery? The example this section is based on can be found here(make sure to also start the server). The [contenthash] substitution will add a unique hash based on the content of an asset. To get it start faster we can use webpack's cache-loader . I've read everything I can find in the webpack documentation and every relevant link Google produces for two days with no luck. As imports are transformed to require.ensure there are no more magic comments. Suppose there is a directory structure that looks like this: By using the import function in our application code: webpack will generate a chunk for each file in the animals directory. Recovering from a blunder I made while emailing a professor. Built at: 02/04/2019 6:39:47 AM This issue had no activity for at least three months. Now if we want to use the lion module, I should not see a new request, but only a confirmation that the lion module has been executed: Here's a diagram to supplement what's been accumulated so far: We've saved this section until last because of its peculiarities. In this example, the resulting RegExp object will be /^\\.\\/. + 28 hidden modules Operating System: OSX 10.13.6 (17G65) CommonJS or AMD modules cannot be consumed. It's what is considered a "weak" dependency. As imports are transformed to require.ensure there are no more magic comments. Including hashes related to the file contents to their names allows to invalidate them on the client-side. It can decrease the output size of a chunk. Please pay attention to these enforcements before you read on: Version 2 of webpack supports ES6 module syntax natively, meaning you can use import and export without a tool like babel to handle this for you. ? Basically, this technique ensures that certain modules are only loaded when they are required by the users. Note that webpackInclude and webpackExclude options do not interfere with the prefix. How to get dynamic imports to work in webpack 4, How Intuit democratizes AI development across teams through reusability. The function name or variable name is the identifier under which the value is exported. However, according to MDN and Google Developer Website, dynamic import should support loading scripts from remote source. Let's call your projects Lib (your React component library) and App (the library consumer). 7 comments LASkuma commented on Nov 5, 2018 edited webpack-bot added the inactive label on May 31, 2019 alexander-akait closed this as completed on May 31, 2019 colscott mentioned this issue on Jun 16, 2019 to your account, I made a vue component package my-custom-comp, which contains dynamic import: Learn 5 Optimization Tips for Webpack Step by Step Somnath Singh in JavaScript in Plain English Coding Won't Exist In 5 Years. Thereby I am using webpacks dynamic import syntax like so import('../images_svg/' + svgData.path + '.svg') sadly this doesn't work. If you type cat in the input and then press the button, you'll notice an error in the console: And this should make sense because, as it's been mentioned previously, the weak import expects that the resource should already be ready to be used, not to make webpack take action in order to make it available. rev2023.3.3.43278. You can think of a dynamic expression as anything that's not a raw string(e.g import('./path/to/file.js')). This feature relies on Promise internally. Caching | webpack Why are Suriname, Belize, and Guinea-Bissau classified as "Small Island Developing States"? This section covers all methods available in code compiled with webpack. By clicking Sign up for GitHub, you agree to our terms of service and Webpack: Common chunks for code shared between Webworker and Web code? // Do something with lodash (a.k.a '_') // imagine we had a method to get language from cookies or other storage, /* webpackExports: ["default", "named"] */, /* webpackExclude: /\.noimport\.json$/ */, // in theory; in praxis this causes a stack overflow, /* optional, default /^\.\/. Lazy Loading is a hot topic for the optimization of web applications. From this list of plugins, the only plugin that might be the culprit is dynamic-import-webpack, A small plugin to make dynamic imports i.e. But I'm not being able to dynamically load external libraries from variables. To get it start faster we can use webpack's cache-loader. Webpack Bundler , . A link for the above diagram can be found here. Ive tried several different variations of the imports. Operating System: windows Webpack adds a really nice feature to the dynamic imports, the magic comments. Moreover, all the modules that this newly loaded chunk contains will be registered by webpack. [38] ./sources/styles/anytime.css 39 bytes {0} [built] Code splitting with webpack and TypeScript | Spencer Miskoviak The compiler ensures that each dependency is available. But Webpack can detect files to bundle when it is given a string interpolation in require() like: @sokra @evilebottnawi Any updates on this issue? Dynamic imports - this is my method of code splitting (page by page). I am trying to implement the same hook in Preact + Vite: dynamic .