I'm new to Webpack and React. I'm building an app using react, and today tried to create a build for the first time (i'm using create-react-app).
When trying to debug using Chrome dev tools, I can see all my Components using the map file generated by webpack/babel, however I get an error when placing a breakpoint inside a basic map method, and trying to access the value of the current item, or the mobx store items.
It's obviously working fine in development mode.
I guess i'm missing something with the configuration?
Thanks,
Currently fixed it by setting mangle=false in the uglify plugin. This causes uglify to not change variable names, so the map file has no problem to map to the real variables.
Related
I'm currently implementing the Monaco Editor from Microsoft (https://github.com/microsoft/monaco-editor), with a plugin for yaml validation, autocompletion, etc. . (https://github.com/remcohaszing/monaco-yaml) in our react js APP.
Maybe it is also important to tell you, that our authentication process gets managed via Keycloak.
When I'm running my code in development (React-scripts start) everything is working as expected.
I can create the editor, the schema gets implemented correctly and autocompletion is also working.
BUT as soon as I try to use the editor in PRODUCTION Build it seems that it cant load my workers correctly, following the editor is not working as it should.
I always get these errors in production:
I tried to use monaco-editor-webpack-plugin with React Rewired but it didnt have an positive effect either.
I also tried to use the worker loader to load the workers, but it also didnt help
Any more Ideas how I can fix this ? Has this to do something with CORS ? Because it tries to load files in a url? Or am I missing something ?
Thanks in advance
What I tried: Monaco Webpack Plugin, plain webpack, worker-loader
Expected Behaviour: Monaco Editor with Monaco Yaml working in production build.
Current behaviour: Working fine in development build, cannot load workers in production.
The problem was, that my keycloak (on a different port) rejected to load the working scripts. After handling this problems, the editor is working fine.
I've created a basic Create React App with TypeScript template
npx create-react-app cra-test --template typescript
I added just a simple MyButton component and passed a on click handler to it.
When I'm profiling it with Chrome DevTools links to the source in the profiler are incorrect and not working as if there where no source maps.
When I run console.trace in my onClick handler stack trace looks good.
How can I get correct links to source files in the profiler tab working?
Thanks!
In order to get this working you need to change webpack's setting
devtool: 'eval-source-map'
You can set it using config-overrides.js (react-app-rewired).
Probably there are some other source map types that will work but that one gives you the most detailed information.
More on source map types here
https://webpack.js.org/configuration/devtool/
You can read about devtool setting here.
https://webpack.js.org/guides/development/#using-source-maps
I was trying to integrate a React.js app in Cordova. Everything goes well, but I was not able to debug the app in the simulator. With chrome://inspect it seems like there's no way to do it, because I can only see the "compiled code". Any solution? Thanks
Maybe there is another better way, but what do the trick for me is to build react with some custom files that i took from node_modules/react-scripts/
(i do that, to avoid react eject)
You need all the sources map on your app.
React by default, use a certain webpack config, but that config doesn't work in your phone.
By default, react use this
You can check it on the file node_modules/react-scripts/config/webpack.config.js
What i do, is to build react with the next webpack config
devtool: "eval-source-map",
So you must
Copy these files on your source code and adapt some imports (there are some import with relative path) You only need these two files
node_modules/react-scripts/scripts/build.js
node_modules/react-scripts/config/webpack.config.js
On the first one, modify it to use the second one,
On the second one, add this devtool: "eval-source-map"
Create new task on package.json , new custom build to use the script your custom build.js
Build with this script, and copy all the source maps with your code, and thats it.
The debug could crash sometimes, (i try it also with iphone + safari, sometimes works, sometimes don't so you must keep trying)
On android tend to work in a better way.
The debug is a little bit slow in compare to the web debug.
I hope this works for you too.
(Sorry for my bad English)
I am starting to help someone with a new project. This project is React (React Native as is a mobile app).
The project is working fine on her laptop (in her browser), and when I scan the Expo QR code, the app works fine on my Android device.
However, trying to run it in my browser is throwing all these errors:
The 'Can't resolve' error doesn't make sense, because the correct react native files are there. Is this a cache problem? I have tried deleting the .expo/web/cache folder and starting over.
Also, why are there multiple errors in my console, but only one being shown in the information on the actual web page? Does this mean that the single error being shown is causing all the other errors, or it is the only one which needs fixing, or will it show the next error when I fix the one that is being shown?
Thanks
Seems to have been a known problem re babel. See the links below:
https://github.com/babel/babel-loader/issues/173
how to solve this error You may need an appropriate loader to handle this file type
I minified/built my app that uses ExtJS 4.2.0 (free version) using Sencha SDK Tools 2.0.0 beta3, and the app was built successfully. However, when I try deleting the old "app" folder containing my old classes, the app no longer works.
I also tried generating a new app using Sencha CMD 4.0.1.45 and then adding my classes, but the results are the same.
I am confused why this happens, because as I understood it, your old classes are not needed to deploy production app. In fact, the only javascript files you need to include in your "index.html" file are "ext.js" and "app-all.js".
I used Firebug and saw in the DOM that the app, along with my classes, are loaded.
I also noticed that "app-all.js" defines classes like this:
Ext.define("MyApp.view.MyClass"...
Is this really how it is supposed to behave? or am I missing something?
Thanks in advance!
Okay, I got it. A .js file in my application calls Ext.require on itself, causing the app wiring go crazy.