Configurable URL length limit

[michaelsproul]

Description

It may be useful to have a way of bumping the URL length limit for the HTTP API. Some VCs will use long query strings to determine the validator indices of a bunch of pubkeys, e.g. Nimbus: status-im/nimbus-eth2#4980.

Version

v4.2.0

[aoikurokawa]

@michaelsproul
Hello.

I am considering to work on this issue. I have checked some libraries like warp and hyper so far.
Then I found this code in hyper.
https://github.com/hyperium/hyper/blob/96d54b10689042222032f312216ce1df457982f8/src/proto/h1/role.rs#L155-L157

We can not request like 1024 validator's public key as query.

So I think we have to handle 414URI Too Long error in handle_rejection function.

lighthouse/common/warp_utils/src/reject.rs

Line 144 in 441fc16

pub async fn handle_rejection(err: warp::Rejection) -> Result<impl warp::Reply, Infallible> {

[michaelsproul]

Thanks for looking into this @aoikurokawa.

I think the best thing would be to reply with a 414 when the request is too large.

To address the underlying issue of not being able to request enough validators, I've opened a PR to the spec: ethereum/beacon-APIs#367

And a draft impl in Lighthouse: #4872

[michaelsproul]

Closing as obsoleted by #4872.