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0 pointschrismorgan11mo ago0 comments

You’re not getting it: we’re not talking about the server producing templated HTML, which is fine; but rather the server producing JSON, and then the client dropping strings from that object directly into serialised HTML. That’s a problem, because the only way to be safe is to entity-encode everything, but then when you use a string in a context that doesn’t use HTML syntax, you’ll get the wrong result.

It’s not an unnecessary complication. You fundamentally need to know what format you’re embedding something into, in order to encode it, and the server can’t know that.

Depending on what you do, you may want it unencoded, encoded for HTML data or double-quoted attribute value state (& → &, < → <, " → "), encoded for a URL query string parameter value (percent-encoding but with & → %26 as well), and there are several more reasonable possibilities even in the browser frontend context.

These encodings are incompatible, therefore it’s impossible for the server to just choose one and have it work everywhere.

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naasking11mo ago

> It’s not an unnecessary complication. You fundamentally need to know what format you’re embedding something into, in order to encode it, and the server can’t know that.

There are two cases here:

1. Backend endpoints are specifically tied to the view being generated (returns viewmodels), in which case the server knows what the client is rendering and can encode it. This frankly should be the default approach because it minimizes network traffic and roundtrips. The original code displayed is perfectly fine in this case.

2. Endpoints are generic and the client assembles views by making multiple requests to various endpoints and takes on the responsibility that server-side frameworks used to do, including encoding.

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