Relative URL support

[ufoscout]

I am trying to use surf to call my backend from a Yew-based WASM frontend running in the browser.

HTTP calls to the backend are typically performed by a frontend application using relative URLs; anyway, this is not possible with surf as every attempt to send a call with a relative URL generates a panic with this message in the browser console:

panicked at 'called `Result::unwrap()` on an `Err` value: RelativeUrlWithoutBase', /home/ufo/.cargo/registry/src/github.com-1ecc6299db9ec823/surf-2.2.0/src/client.rs:548:42

Stack:

init/imports.wbg.__wbg_new_59cb74e423758ede@http://127.0.0.1:3000/index-3c6d44c9390fc4f2.js:302:19
console_error_panic_hook::Error::new::hd990297f532a9234@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[7058]:0x186a2c
console_error_panic_hook::hook_impl::h80677aeedc307843@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[793]:0xb2e8a
console_error_panic_hook::hook::h1ee90794f5cd7865@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[7797]:0x190de1
core::ops::function::Fn::call::h474424fdd5f0e50d@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[6506]:0x17e209
std::panicking::rust_panic_with_hook::hbdbceb5cd158bf19@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[1843]:0xfd0a2
std::panicking::begin_panic_handler::{{closure}}::h9995bb2f0de4bb38@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[2837]:0x1275b0
std::sys_common::backtrace::__rust_end_short_backtrace::hc7608161a467c002@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[8331]:0x197971
rust_begin_unwind@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[7505]:0x18cfe2
core::panicking::panic_fmt::h3ab5417155b7ba3b@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[8332]:0x1979a7
core::result::unwrap_failed::h9bf99bca88ba05dc@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[3361]:0x138737
core::result::Result<T,E>::unwrap::h33bc93175c1bc582@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[2644]:0x1205a8
surf::client::Client::url::h39313a8f3aaa19cf@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[1191]:0xd4d83
surf::client::Client::get::ha967bf82289d17fc@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[1862]:0xfe06a
ajars_surf::AjarsSurf::request::h6ae85bb0d856083f@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[298]:0x6b5f8
<web_yew_surf::Model as yew::html::component::Component>::update::{{closure}}::h6bffacbfd91ec472@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[258]:0x61af7
<core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h402db801b284075c@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[695]:0xa8637
<yew::html::component::scope::Scope<COMP> as yewtil::future::LinkFuture>::send_future::{{closure}}::ha636b22ecbda53c1@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[323]:0x70b63
<core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::hf132d4cc883e3691@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[2139]:0x10b6e4
wasm_bindgen_futures::task::singlethread::Task::run::h7fe7783a8d04cc40@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[555]:0x9738b
wasm_bindgen_futures::queue::QueueState::run_all::h0079a01c6732e655@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[706]:0xa9b02
wasm_bindgen_futures::queue::Queue::new::{{closure}}::h450bfa8f161ec151@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[4272]:0x15119c
<dyn core::ops::function::FnMut<(A,)>+Output = R as wasm_bindgen::closure::WasmClosure>::describe::invoke::he5c7b3ad9ac2248f@http://127.0.0.1:3000/index-3c6d44c9390fc4f2_bg.wasm:wasm-function[1858]:0xfdd73
__wbg_adapter_27@http://127.0.0.1:3000/index-3c6d44c9390fc4f2.js:222:10
real@http://127.0.0.1:3000/index-3c6d44c9390fc4f2.js:191:20

I am also surprised that it panics instead of returning an error.

[Fishrock123]

@yoshuawuyts

[Fishrock123]

The short answer here is that we won't support that because the url crate does not support it.