Description
🐞 bug report
Affected Package
The issue is caused by package @angular/service-worker
Is this a regression?
No
Description
We have an hybrid stack with old school PHP pages mixed with an Angular SPA, and the Angular app has a wildcard route redirecting all non-SPA navigations to the legacy PHP stack.
Combined with using the ngsw-bypass query param, the Angular Service Worker works great in most situations. However, it does break HTML forms POST submit, as the Service Worker would then return the app shell (even though req.method was post), causing the SPA to send a new GET request with the ngsw-bypass query param, and breaking the form submission.
To be clear, the entire reason why this is an issue for us is that we have way too many unknown PHP POST endpoints to be able to exclude them all from the navigationUrls regexes (and they often live next to actual SPA routes); the issue does not exist if the POST endpoint is excluded from navigationUrls.
Patching ngsw-worker.js at build time solves our issue, however, considering that POST requests aren't supported by the Cache API / can't really be cached by Service Workers, that upload progress events are broken as well, and that (in our case) HTML form POST submits are broken when form action targets match navigationUrls, I wonder it there's a point for the Angular Service Worker to handle POST requests in the first place.
i.e., is there any downside for the Angular Service Worker to not handle any POST requests at all like we've done?
if (req.method === 'POST' || req.headers.has('ngsw-bypass') || /[?&]ngsw-bypass(?:[=&]|$)/i.test(requestUrlObj.search)) {
return;
}
Looking through the various GitHub issues for related bugs, I feel that this would make real-life Service Worker deployments much easier.
Alternatively, I would argue that the Angular Service Worker should not return the app shell for req.mode === 'navigation' requests if req.method is not GET, in order to stay on the safe side.
🔬 Minimal Reproduction
I've created a small repro at https://github.com/laurentgoudet/angular-service-worker-submit-post-bug: just git checkout, yarn, node server.js, and open http://localhost:8080: the form submit would be broken once the Service Worker has bootstrapped
🌍 Your Environment
Angular Version:
laurent@Laurents-MacBook-Pro webapp [laurent-sw-fix] $ ./node_modules/.bin/ng version
_ _ ____ _ ___
/ \ _ __ __ _ _ _| | __ _ _ __ / ___| | |_ _|
/ △ \ | '_ \ / _` | | | | |/ _` | '__| | | | | | |
/ ___ \| | | | (_| | |_| | | (_| | | | |___| |___ | |
/_/ \_\_| |_|\__, |\__,_|_|\__,_|_| \____|_____|___|
|___/
Angular CLI: 9.0.5
Node: 12.4.0
OS: darwin x64
Angular: 9.0.5
... animations, cli, common, compiler, compiler-cli, core, forms
... language-service, localize, platform-browser
... platform-browser-dynamic, platform-server, router
... service-worker
Ivy Workspace: Yes
Package Version
-----------------------------------------------------------
@angular-devkit/architect 0.900.3
@angular-devkit/build-angular 0.900.3
@angular-devkit/build-optimizer 0.900.3
@angular-devkit/build-webpack 0.900.3
@angular-devkit/core 9.0.3
@angular-devkit/schematics 9.0.5
@angular/cdk 9.1.1
@angular/material 9.1.1
@ngtools/webpack 9.0.3
@nguniversal/builders 9.0.1
@nguniversal/common 9.0.2
@nguniversal/express-engine 9.0.2
@schematics/angular 9.0.5
@schematics/update 0.900.5
rxjs 6.5.4
typescript 3.7.5
webpack 4.41.2