Add hot-only option to allow setting only-dev-server from cli or config

[SimenB]

I currently have to mess around with entry manually as I want only-dev-server. This allows me to just add the options, or cli flag.

current:

entry: [
  'webpack-dev-server/client?http://0.0.0.0:3030',
  'webpack/hot/only-dev-server',
  origConfig.entry
],
devServer: {
  host: '0.0.0.0',
  port: 3030,
  hot: true,
},

wanted:

devServer: {
  host: '0.0.0.0',
  port: 3030,
  hotOnly: true,
  inline: true
},

Ideally I'd PR this into webpack-dev-server@1 (as IE8 support is dropped, we'll probably never upgrade), but there doesn't seem like there's a branch for it.

[SimenB]

@sokra ping

[sokra]

"hotOnly" => "hot-only" for the CLI argument

[SimenB]

yargs normalizes it, so both works. I can change it though 😄

[SimenB]

@sokra Updated

[SimenB]

@sokra ping.

Also, thoughts on a v1 branch?

[SimenB]

@sokra ping.

[sokra]

Thanks

[harmony7]

Hi, I have a comment on this. It seems that with --hot-only, the HotModuleReplacementPlugin plugin does not get loaded as it would with --hot. At the current time I can work around this problem by supplying both --hot and --hot-only to get the behavior I want.

Digging deeper it seems that this processing is done in webpack/bin/convert-argv.

        ifBooleanArg("hot", function() {
            ensureArray(options, "plugins");
            var HotModuleReplacementPlugin = require("../lib/HotModuleReplacementPlugin");
            options.plugins.push(new HotModuleReplacementPlugin());
        });

How would we go about getting this fixed? Is it something that needs fixing in webpack? (Why is it webpack's job to handle ARGV for webpack-dev-server, anyway?)

[SimenB]

That's by design. It's for the entrypoint webpack/hot/only-dev-server. You still need to activate hmr with hot.

The goal of this option was to avoid supplying entrypoints, as can be seen in my opening post

[harmony7]

Thanks for your response.

Okay. I saw this code change you made in Server.js:

    this.hot = options.hot || options.hotOnly;

So I thought you were trying to make it so you had to specify only one or the other to activate hot