Where to use this about cloudflare-edge-proxy

[shalomvolchok]

Yes, you can use npm modules on a CF worker. Just use Webpack to bundle one final script.

If this was your worker script worker.js:

import cloudflareEdgeProxy from "cloudflare-edge-proxy";

const config = {
    defaultBackend: "https://example.com"
};

const proxy = cloudflareEdgeProxy(config);

addEventListener("fetch", event => {
    event.respondWith(proxy(event));
});

Then you could build a single bundle for CF with a Webpack config something like this:

module.exports = {
    entry: { worker: "./worker" },
    target: "webworker",
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /(node_modules)/,
                use: {
                    loader: "babel-loader",
                    options: {
                        presets: [
                            [
                                "@babel/preset-env",
                                {
                                    targets: { chrome: "70" }
                                }
                            ]
                        ]
                    }
                }
            }
        ]
    }
};