marketui v0.2

This is a long-overdue feature and bugfix release. I planned to include WebSocket books too (with full depth) but didn't make it due to lack of time. Since this version has served well for months, let's release it anyway.

Highlight of this release is the opt-in automatic updating of market and book tables. I found manual update mode still valuable so keeping it for now.

User-facing changes:

• added checkbox toggle to enable auto-updating of market and book data
• show selected market price in browser tab title
• show quote currency ticker in book column header
• made tables a bit wider to fit longer numbers
• added thin 1 px border around tables
• slightly reduced font size to fit more stuff
• removed bluish background from tables
• fixed book scroll position not getting reset when selecting a different market

Internal changes:

• added graceful cancellation of requests
• fixed possibility to start concurrent requests for book or market data (watching books for multiple markets is not supported for now)
• extracted and reused code for handling fetches and auto-updating
• did some separation of "business" data from UI state data (and code updating them)
• reduced the amount of logging
• fixed ~10 bugs (mostly state management and error handling)

Full list of changes is here.

I learned something about promises and error handling. TL;DR: promises are error-prone (surprised?). I'm recording my web dev "adventures" in the Git log, mostly for myself, but you may find it fun to read too.

If marketui was useful to you, feel free to tip me with a bit of DCR at DsefC8JBDkkyASdXrqA3HDzBByNhffLMjQS

marketui v0.1

Welcome the initial public release of marketui!

This project provides a web page that you download and open locally to quickly check Poloniex order books.

There is so much more to do but I'd like to share what already works:

• show/update a list of markets and their prices
• show/update order books for a selected market (up to 100 price levels)
• updating is done manually for now

It is not too exciting when you have to click to update (what?!) but it already shows 100 price levels for each book vs 50 in the new Poloniex UI. And because it is so light and local you can check prices and books in sub-second time.

Next milestone is to update books and markets automatically. A bunch of code for that is already there and working but it is deactivated until I fix a few remaining edge cases.

Credits: I would like to thank Poloniex for shutting down the nice-and-just-works old UI in favor of the new fancy-and-inconvenient one, for giving me enough impulse to kickstart this journey.

Expectations: This is a small hobby project to get the most needed data and learn some web stack along the way. Please don't expect much ;)

Check the README for usage instructions.

Happy book reading!