Most useful eslint rules for networking code (async/await/promises)

The main caveat is that you have to use typescript. Put this into the rules section of your .eslintrc.json:

"@typescript-eslint/await-thenable": "error",
"@typescript-eslint/require-await": "error",
"@typescript-eslint/no-floating-promises": "error"

You'll also need to tell eslint where your tsconfig file is:

"parserOptions": {
    "project": "tsconfig.json"
}

Then if you write code like this, where you don't await an asynchronous call:

async function f() {
    await fetch('a')
    doSomethingElse()
    fetch('b')
}

Then you'll get a helpful error message, which pops up over the text in vscode if you're using the eslint extension:

temp.ts
4:5   error  Promises must be handled appropriately or explicitly marked as ignored with the `void` operator  @typescript-eslint/no-floating-promises

You'll also get errors if an async function has no awaits or if you await a sync function.