Upgrading to Angular 10 - Fix CommonJS or AMD dependencies can cause optimization bailouts

Question

I am trying to upgrade my angular 9 app to angular 10 version, but getting below warning after the upgrade

rxjs\BehaviorSubject.js depends on rxjs-compat/BehaviorSubject

Any idea how to fix this?

Solution 1

When you use a dependency that is packaged with CommonJS, it can result in larger slower applications

Starting with version 10, Angular now warns you when your build pulls in one of these bundles. If you’ve started seeing these warnings for your dependencies, let your dependency know that you’d prefer an ECMAScript module (ESM) bundle.

Here is an official documentation - Configuring CommonJS dependencies

In your angular.json file look for the build object and add

allowedCommonJsDependencies

as shown below -

"build": {
  "builder": "@angular-devkit/build-angular:browser",
  "options": {
     "allowedCommonJsDependencies": [
        "rxjs-compat",
         ... few more commonjs dependencies ... 
     ]
     ...
   }
   ...
},

Solution 2

try replacing the rxjs imports rxjs/internal/operators with rxjs/operators.

ex:

import { catchError, retry } from 'rxjs/internal/operators';

with

import { catchError, retry } from 'rxjs/operators';

Solution 3

It is recommended that you avoid depending on CommonJS modules in your Angular applications. Depending on CommonJS modules can prevent bundlers and minifiers from optimizing your application, which results in larger bundle sizes. Instead, it is recommended that you use ECMAScript modules in your entire application.Still you don't care about your bundling size,

To disable these warnings, you can add the CommonJS module name to allowedCommonJsDependencies option in the build options located in angular.json file.

"build": {
  "builder": "@angular-devkit/build-angular:browser",
  "options": {
     "allowedCommonJsDependencies": [
        "rxjs-compat"
     ]
     ...
   }
   ...
},

Source

Solution 4

For RXJS library you can do following changes.

For imports such as 'rxjs/internal/<anything>' and 'rxjs/index', replace it with just 'rxjs'.

For imports such as 'rxjs/internal/operators', replace it with 'rxjs/operators', which is mentioned in @Janardhan Burle's answer.

Or replace just rxjs

Solution 5

Just change the import:

from:

import { BehaviorSubject } from 'rxjs/internal/BehaviorSubject';

To:

import { BehaviorSubject } from 'rxjs';

View more solutions

Comments

[Jonathan Stellwag]

Can you check if you once did not import from rxjs instead from rxjs/behaviorsubject.

[Ora]

@JonathanStellwag I have imported it like this - import { BehaviorSubject } from 'rxjs' and everything works fine for Angular 9. But for Angular 10 it does not. I am facing the same issue for map operator as well - It says WARNING in ..\node_modules\rxjs\operators\map.js depends on rxjs-compat/operators/map. CommonJS or AMD dependencies can cause optimization bailouts.

[JSON Derulo]

Does this answer your question? Angular 10 Upgrade - Fix CommonJS or AMD dependencies can cause optimization bailouts

[Ora]

Thanks for answering. I would still like to know if there are any ECMAScript modules that are recommended as it's substitute? instead of disabling the warnings.

[StackOverflowUser]

This did not get rid of the warning messages for me.

[Niral Munjariya]

Same for me, I am using lodash and added it to "allowedCommonJsDependencies" but still the same warning. Any idea?

[JSON Derulo]

@StackOverflowUser please have a look at this answer: stackoverflow.com/a/62589268/5470544

[Leonardo Rick]

I can't find the key word to suprress on my case: WARNING in /home/leonardo/iq/web-iqbot/node_modules/@firebase/app/dist/‌​index.cjs.js depends on '@firebase/component'. CommonJS or AMD dependencies can cause optimization bailouts. For more info see: https://angular.io/guide/build#configuring-commonjs-dependen‌​cies

[Gunjan Khanwilkar]

@LeonardoRick Try putting something like this for firebase dependencies: "allowedCommonJsDependencies": [ "firebase", "@firebase/app", "firebase/app", "@firebase/functions", "@firebase/performance", "@firebase/remote-config", "@firebase/component" ], In your case just add '@firebase/component' keyword in the existing list and it should work.

[Leonardo Rick]

It worked! Thank you. In my case it was multiple warnings inside @firebase and It only dissapeared when I added all of them as allowed. I was trying to make them dissapear one by one

[freedev]

@GunjanKhanwilkar any chance you improve your answer explaining clearly why packaging with CommonJS can result in larger slower applications?

[Gunjan Khanwilkar]

@freedev I have updated the link in my answer! You could find a good explanation here - web.dev/commonjs-larger-bundles Cheers!

[Antoniossss]

Altough advice is correct, it assumes it is I that uses CommonJS or AMD, while the most common scenario is that I am using 3rd party lib that dependes on those.

[bene-we]

Replacing with just 'rxjs' did the trick for me, thanks

[ymssa___]

Yes. That should do the job. Glad it could help.

[Maxim Georgievskiy]

For anyone who searches for the file where it should be added - angular.json in the root directory of your project.

[Gunjan Khanwilkar]

@MaximGeorgievskiy Good catch newbies might have difficulties to locate the file.. I have updated the answer for the same thanks!

[Aniket kale]

Replacing with just 'rxjs' did the trick for me too, thanks

[liakoyras]

Is this just suppressing the warning, or does this also help with the optimization?

[Adel Kedjour]

@liakoyras this is how we import BehaviorSubject in RxJS v6+ learnrxjs.io/learn-rxjs/subjects/behaviorsubject

[liakoyras]

Yes I understand that, my question is wether the new way helps only with suppressing the compiler warning, or is v6+ indeed a new ES6 modulization for rxjs (while the older versions were CommonJS).

[Adel Kedjour]

Hi @liakoyras sorry for late replay. The RxJS 6 brings improvements in modularity, a boost in performance and easier to debug call stacks. The RxJS team has made a solid effort on making this release as backward compatible as possible. auth0.com/blog/whats-new-in-rxjs-6

[mstgnz]

worked angular@12

[Benjamin Aronsson]

This will only silence the warning, the dependencie will include the entire commonjs in your bundle leading to a bigger bundle size than necesarry

[Raphael Pinel]

For lodash, use lodash-es instead: npmjs.com/package/lodash-es