Bad Response + Manifest: Line: 1, column: 1, Syntax error. + Failed to register a ServiceWorker

[Becca37]

Issue: getting error Uncaught (in promise) TypeError: Failed to register a ServiceWorker for scope ('https://localhost:44376/') with script ('https://localhost:44376/serviceworker'): A bad HTTP response code (500) was received when fetching the script.
localhost/:1

I see a couple of references to this set of errors, but each issue refers back to a closed issue, and that closed issue appears to have been deleted. So, I'm hoping someone can point me in the right direction for me to find my error. TIA! :0)

• ASP NET Core 5.0
• C#
• Razor Pages
• running on localhost using HTTPS

Stuff ...

• If I put the manifest.json's location in the browser address bar, it displays the file fine.
• I have turned off Javascript debugging via Tools > Options > Debugging > General
• I have the checkbox Update on reload checked in developer tools > application > service workers
• After running, a serviceworker in present at developer tools > application > service workers and shows (and remains the same except for the incrementing numer if I unregister it and reload the page):

Received 12/31/1969 7:00:00 pm 
Status #dddd is redundant

manifest.json in wwwroot folder:

{
	"name": "App Name",
	"short_name": "AppAcronym",
	"icons":
	[
		{
			"src": "/images/manifest/icons-192.png",
			"type": "image/png",
			"sizes": "192x192"
		},
		{
			"src": "/images/manifest/icons-512.png",
			"type": "image/png",
			"sizes": "512x512"
		}
	],
	"start_url": "/",
	"background_color": "#17a2b8",
	"display": "standalone",
	"scope": "/",
	"theme_color": "#17a2b8"
}

Startup.cs addition, items removed for berevity; services.AddMvc() added only to troubleshoot as some internet references suggested that might be the answer; no change in behavior for me:

		{
			services.AddRazorPages();
			services.AddMvc();
			services.AddProgressiveWebApp();
		}

view page source after building and running shows expected entries in head and at end of body:

<meta name="theme-color" content="#17a2b8" />
<link rel="manifest" href="/manifest.webmanifest" />
<script nws-csp-add-nonce='true'>'serviceWorker'in navigator&&navigator.serviceWorker.register('/serviceworker', { scope: '/' })</script>

errors in Chrome developer console:

A bad HTTP response code (500) was received when fetching the script.
localhost/:1 

GET https://localhost:44376/manifest.webmanifest 500

manifest.webmanifest:1 Manifest: Line: 1, column: 1, Syntax error.
localhost/:1 

Uncaught (in promise) TypeError: Failed to register a ServiceWorker for scope ('https://localhost:44376/') with script ('https://localhost:44376/serviceworker'): A bad HTTP response code (500) was received when fetching the script.
localhost/:1 

GET https://localhost:44376/manifest.webmanifest 500
manifest.webmanifest:1 

Manifest: Line: 1, column: 1, Syntax err

Ideas? Suggestions?

[Budsy]

This error display in Chrome and Edge developer's tools console error listing shed light on the problem when I had this same issue. The domain part of the path seemed to be missing in the request paths. I eliminated the errors by removing the BaseRoute = "/" that I had in my .NET 5 Startup configuration settings for the AddProgressiveWebApp method.

Uncaught (in promise) DOMException: Failed to register a ServiceWorker: The origin of the provided scriptURL ('https:serviceworker') does not match the current origin ('https://').

GET https://manifest.webmanifest/
net::ERR_NAME_NOT_RESOLVED

[Becca37]

Thanks, @Budsy! Since I do not have any configuration settings added to the AddProgressiveWebApp method and the error messages are different I don't think that's my issue. I'd certainly try removing a slash, if I had one. :0)

[ArisNance]

Using https:// worked for me!