Trait TransportInstaller 

pub trait TransportInstaller:
    Send
    + Sync
    + 'static {
    // Required method
    fn build(
        &self,
        profile: &TransportProfile,
    ) -> Result<TransportConfig, TransportProfileError>;
}

Builds the quinn::TransportConfig a leg installs.

A leg with a TransportProfile and no installer of its own uses DefaultInstaller, so supplying one replaces exactly one step and nothing else: the leg still installs whatever comes back, still installs it before its endpoint exists, and still refuses a leg that names a raw quinn::TransportConfig as well as a profile.

What this is for: a base configuration and a profile

A leg takes a raw config or a profile, never both — see ProxyError::TransportConfigAndProfile, which is where the reason is written out. The short form is that quinn::TransportConfig can be neither cloned nor read back, so no code here can accept a caller’s config and return a modified copy of it.

An installer is how a caller has both anyway, and it works because it builds the base rather than being handed one: build constructs its own quinn::TransportConfig, applies the profile over it with TransportProfile::apply_to, and returns the result. Nothing is copied, so nothing is silently dropped, and the caller’s own settings survive because the caller is the one making them.

Send + Sync + 'static because one installer serves every connection a leg carries, for as long as the proxy runs, from whichever task accepts them.

Required Methods

fn build( &self, profile: &TransportProfile, ) -> Result<TransportConfig, TransportProfileError>

Turn profile into the config this leg will install.

An error refuses the connection instead of falling back to a default. A leg that connected anyway would be running with parameters nobody chose while reporting success, which is the one outcome every rule in this module exists to prevent.

Owned, not Arc

The return type is a plain quinn::TransportConfig and the reason is what the caller may still need to do to it. A QUIC-level capture sink is installed by mutating a quinn::TransportConfig, and an Arc that may already be shared cannot be mutated — Arc::get_mut hands back nothing the moment a second handle exists. An installer that returned one would therefore be unusable on any leg that also asked for a capture, and the only way to keep such a leg working would be to skip the installer: a caller who supplied one would find it never called, with nothing saying so. Handing back the value means the leg can attach whatever else it owes to it and every setting survives.

The leg wraps the result in an Arc itself, once, after it has finished with it. An implementation that has an Arc already should build a fresh config rather than trying to unwrap one — that is the same rebuild-per-leg this trait exists for.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl TransportInstaller for DefaultInstaller