use std::{
net::SocketAddr,
sync::Arc,
time::{Duration, Instant},
};
use anyhow::Context;
use async_trait::async_trait;
use nanorpc::{JrpcRequest, JrpcResponse, RpcTransport};
use reqwest::dns::Resolve;
pub struct FrontedHttpTransport {
pub url: String,
pub host: Option<String>,
pub dns: Option<Vec<SocketAddr>>,
}
#[async_trait]
impl RpcTransport for FrontedHttpTransport {
type Error = anyhow::Error;
async fn call_raw(&self, req: JrpcRequest) -> Result<JrpcResponse, Self::Error> {
tracing::trace!(
method = req.method,
url = self.url,
host = debug(&self.host),
"calling broker through http"
);
let start = Instant::now();
let mut request_builder = if let Some(dns) = &self.dns {
reqwest::Client::builder()
.no_proxy()
.timeout(Duration::from_secs(10))
.dns_resolver(Arc::new(OverrideDnsResolve(dns.clone())))
.build()
} else {
reqwest::Client::builder()
.no_proxy()
.timeout(Duration::from_secs(10))
.build()
}
.unwrap()
.post(&self.url)
.header("content-type", "application/json");
if let Some(host) = &self.host {
request_builder = request_builder.header("Host", host);
}
let request_body = serde_json::to_vec(&req)?;
let response = request_builder
.body(request_body)
.send()
.await
.context("cannot send request to front")?;
let resp_bytes = response.bytes().await?;
tracing::trace!(
method = req.method,
url = self.url,
host = debug(&self.host),
resp_len = resp_bytes.len(),
elapsed = debug(start.elapsed()),
"response received through http",
);
Ok(serde_json::from_slice(&resp_bytes)?)
}
}
struct OverrideDnsResolve(Vec<SocketAddr>);
impl Resolve for OverrideDnsResolve {
fn resolve(&self, _name: reqwest::dns::Name) -> reqwest::dns::Resolving {
let addrs = self.0.clone();
Box::pin(async move {
let b: Box<dyn Iterator<Item = SocketAddr> + Send + 'static> =
Box::new(addrs.into_iter());
Ok(b)
})
}
}