There's a post on the
fetch() API by Ludovico Fischer doing the rounds. As a co-instigator for adding the API to the platform, it's always a curious thing to read commentary about an API you designed, but this one more than most. It brings together the epic slog that was the Promises design (which we also waded into in order to get Service Workers done and which will improve with await/async) with the in-process improvements that will come from Streams and it mixes it with a dollop of FUD, misunderstanding, and derision.
This sort of article is emblematic of a common misunderstanding. It expresses (at the end) a latent belief that there is some better alternative available for making progress on the web platform than to work feature-by-feature, compromise-by-compromise towards a better world. That because the first version of
fetch() didn't have everything we want, it won't ever. That there was either some other way to get
fetch() shipped or that there was a way to get cancellation through TC39 in '13. Or that subclassing is somehow illegitimate and "non-standard" (even though the subclass would clearly be part of the Fetch Standard).
These sorts of undirected, context-free critiques rely on snapshots of the current situation (particularly deficiencies thereof) to argue implicitly that someone must be to blame for the current situation not yet being as good as the future we imagine. To get there, one must apply skepticism about all future progress; "who knows when that'll be done!" or "yeah, fine, you shipped it but it isn't available in Browser X!!!".
They're hard to refute because they're both true and wrong. It's the prepper/end-of-the-world mentality applied to technological progress. Sure, the world could come to a grinding halt, society could disintegrate, and the things we're currently working on could never materialize. But, realistically, is that likely? The worst-case-scenario peddlers don't need to bother with that question. It's cheap and easy to "teach the controversy". The appearance of drama is its own reward.
Perhaps most infuriatingly, these sorts of cheap snapshots laced with FUD do real harm to the process of progress. They make it harder for the better things to actually appear because "controversy" can frequently become a self fulfilling prophesy; browser makers get cold feet for stupid reasons which can create negative feedback loops of indecision and foot-gazing. It won't prevent progress forever, but it sure can slow it down.
I'm disappointed in SitePoint for publishing the last few paragraphs in an otherwise brilliant article, but the good news is that it (probably) won't slow Cancellation or Streams down. They are composable additions to
fetch() and Promises. We didn't block the initial versions on them because they are straightforward to add later and getting the first versions done required cuts. Both APIs were designed with extensions in mind, and the controversies are small. Being tactical is how we make progress happen, even if it isn't all at once. Those of us engaged in this struggle for progress are going to keep at it, one feature (and compromise) at a time.