Fail when running devServer

[Mister-Hope]

Version

5.0.0-beta.5

Reproduction link

just-a-fresh-template-with-clean-install

Environment info

vue: The term 'vue' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

# I am not sure, but which package is providing a vue command? I am not having `@vue/cli` global installed.

Steps to reproduce

Just open the devServer

What is expected?

No error

What is actually happening?

Because webpack-dev-server is validating config(seems starting from 4.1.0), so the project won't work.

 vue-cli-service serve
 INFO  Starting development server...
[1%] setup (initialize)
 ERROR  ValidationError: Invalid options object. Dev Server has been initialized using an options object that does not match the API schema.
         - options has an unknown property 'overlay'. These properties are valid:
           object { allowedHosts?, bonjour?, client?, compress?, devMiddleware?, headers?, historyApiFallback?, host?, hot?, http2?, https?, ipc?, liveReload?, magicHtml?, onAfterSetupMiddleware?, onBeforeSetupMiddleware?, onListening?, open?, port?, proxy?, setupExitSignals?, static?, watchFiles?, webSocketServer? }
ValidationError: Invalid options object. Dev Server has been initialized using an options object that does not match the API schema.
 - options has an unknown property 'overlay'. These properties are valid:
   object { allowedHosts?, bonjour?, client?, compress?, devMiddleware?, headers?, historyApiFallback?, host?, hot?, http2?, https?, ipc?, liveReload?, magicHtml?, onAfterSetupMiddleware?, onBeforeSetupMiddleware?, onListening?, open?, port?, proxy?, setupExitSignals?, static?, watchFiles?, webSocketServer? }
    at validate (F:\template\vue\node_modules\schema-utils\dist\validate.js:105:11)
    at new Server (F:\template\vue\node_modules\webpack-dev-server\lib\Server.js:31:5)
    at serve (F:\template\vue\node_modules\@vue\cli-service\lib\commands\serve.js:183:20)
    at processTicksAndRejections (internal/process/task_queues.js:95:5)
error Command failed with exit code 1.

I have reported this issue in Plan of Vue Cli 5 and the related commit half a month ago, but the newest version still not fixing this.

See 967f948#r56932418 and #6064 (comment)

[LinusBorg]

Working fine here:

Re can re-visit this when you provide an actual reproduction.

[Mister-Hope]

https://github.com/Mister-Hope/vue-template

I am including other plugins as well, though there maybe a lot deps declared, most of them are common tools, this is the repo I built to provide template for my own projects, but it's not working after beta.4.

Additional Info: I do check with creating a new one, but with an existing preset, and the preset include vue-router vuex and other plugins. Obviously not as simple as your sreenshot.

[LinusBorg]

https://github.com/Mister-Hope/vue-template/blob/295e33c03d272753f3425060e69628c1e7f14197/vue.config.js#L78-L81

These are not valid webpack-dev-server options (see docs). And that's what the error message is telling you.

You likely need to change that to client.overlay:

https://webpack.js.org/configuration/dev-server/#overlay