import-maps VS Playwright

Long time huge fan of JS. I appreciate your calling out the multi-paradigm aspect; having these first class functions & prototype based inheritance has been so flexible.

TC39 has done a great job shaping the language over the years. New capabilities are usually well thought out & integrate well. Async await has been amazing.

The one major miss that makes me so sad and frustrated is modules; js has gotten better everywhere except it's near requirement for build tooling. Being able to throw some scripts on a page and go is still an unparalleled experience in the world, is so direct & tactile an experience. EcmaScript Modules was supposed to improve things, help get us back, but imports using url specifiers made the whole thing non-modular, was a miss. We're still tangled & torn. Import-maps has finally fixed but it's no where near as straightforward, and it still doesn't work in workers, which leaves us infuriatingly shirt of where the past was. https://github.com/WICG/import-maps/issues/2

makes sure your app is getting the download it expects. Adoption is probably pretty minimal though. https://developer.mozilla.org/en-US/docs/Web/Security/Subres...

I think the big thing making this unlikely though is that very few folks use cdns these days. We designed ESM as a module system for the language, but then took a good fraction of a decade to build import-maps, to let us actually use modules in a modular way. Good news, we can finally use modules modularly! https://caniuse.com/import-maps

Bad news? Oh import-maps only works for the simplest case. Doesn't work in webworkers/service workers. https://github.com/WICG/import-maps/issues/2

The point is that single page apps almost always are bundled together, as using CDNs hasn't even been technically possible.

Also, CDNs are kind of somewhat pointless, now that http caches are partitioned by origin (for security reasons). They might have better anycast infrastructure to get the content out faster, but without the caching there's no inherent advantage. The user will download the same jquery file again in each site they go to, no already having it cached anymore. Bah humbug!

https://github.com/WICG/import-maps/issues/2

Bare specifiers has been the tragedy of ESM. Nice module syntax... that is utterly u deoyable & which has had to have awful de-modularizing specifiers hard-coded into each file to make it work. Abominable sin to introduce "modules" to JS/es2015 then spend a decade dragging everyone along with no story for how to have modular modules.

Import-maps are like "here" to fix this on the web... finally... except they only are shipping to the happiest sunniest easiest case, with Web Workers being totally shit out of luck in spite of some very simple straightforward suggested paths forward. https://github.com/WICG/import-maps/issues/2

I think Deno is making pretty good tradeoffs along the way here. This looks like package.json at surface level, but there is a nightmare of complexity under the surface. Typescript, ESM, cjs all have various pressures they create & in Node it's just incredibly tight & tense dealing with packaging, where-as Deno's happy path of Typescript first does not slowly tatters one over time. It really has been super pleasant being free of the previous world, and having something much more web-platform centric, more intented, with less assembly & less building, and more doing the actual coding.

I really hope import-maps eventually get broader support. Maybe this long-dwelling webworker issue should be brought up with WinterCG.

Import maps proposal

The concept of Import Maps was born in 2018 and made its long way until it was declared a new web standard implemented by Chrome in 2021 and some other browsers.

For package managers, you can use something like import maps to let the user specify which path points to what package, and resolve it properly.

Huh. I was about to complain that this breaks with web standards, but apparently it's being proposed as a standard feature: https://github.com/WICG/import-maps

Interesting!

Playwright, an end-to-end test runner;

We start with a project that was bootstrapped with npx create-next-app. For the E2E test we use Playwright and set it up as described in the testing guide provided by Next.js.

Playwright is a powerful tool developed by Microsoft, it allows developers to write reliable end-to-end tests and perform browser automation tasks with ease. What sets Playwright apart is its ability to work seamlessly across multiple browsers (Chrome, Firefox, and WebKit), it provides a consistent and efficient way to interact with web pages, extract data, and automate repetitive tasks. Moreover, it supports various programming languages such as Node.js, Python, Java, and .NET, that’s making it a versatile choice for web scraping projects. Whether you're scraping public data for analysis, building a web crawler, or automating manual workflows, Playwright has you covered.

The consensus I could gather is either use playwright or use a workaround to solve it in the puppeteer layer. The root cause of the bug is a websocket size limitation on the CDP protocol for chromium.

With the advent of tools like Puppeteer and now Playwright, end-to-end testing has become much easier and more reliable. For anyone who's used Selenium in the past, you know what I'm talking about. Puppeteer has opened the way in terms of E2E tooling, but Playwright has taken it to the next level and made it easier to await for certain selectors or conditions to be fulfilled (via locators), thus making tests more reliable and less flaky. Also, it's a game changer that it introduced a test-runner - this made the integration between the headless browser and the actual test code much smoother.

In this tutorial, our main focus will be on Playwright web scraping. So what is Playwright? It’s a handy framework created by Microsoft. It's known for making web interactions more streamlined and works reliably with all the latest browsers like WebKit, Chromium, and Firefox. You can also run tests in headless or headed mode and emulate native mobile environments like Google Chrome for Android and Mobile Safari.

// playwright.config.ts import { defineConfig } from "@playwright/test"; /** * See https://playwright.dev/docs/test-configuration. */ export default defineConfig({ testDir: "./src/pages", reporter: "list", use: { baseURL: "http://localhost:5432/", }, timeout: process.env.CI ? 10000 : 4000, // ... more options });

Issues with Playwright

Fast and reliable end-to-end testing for modern web apps | Playwright

This means you cannot place test files outside of this directory, which was brought up as a question on Github some time ago. Initially, I thought it would be nice to add another folder in the repo called "scripts", but Playwright does not allow multiple testDir values.