split structs from service/globals/mod.rs into separate units

Signed-off-by: Jason Volk <jason@zemos.net>

src/service/globals/resolver.rs

@@ -0,0 +1,72 @@
+use std::{
+	collections::HashMap,
+	error::Error as StdError,
+	future::{self},
+	iter,
+	net::{IpAddr, SocketAddr},
+	sync::{Arc, RwLock as StdRwLock},
+};
+
+use futures_util::FutureExt;
+use hickory_resolver::TokioAsyncResolver;
+use hyper::{
+	client::connect::dns::{GaiResolver, Name},
+	service::Service as HyperService,
+};
+use reqwest::dns::{Addrs, Resolve, Resolving};
+use ruma::OwnedServerName;
+use tokio::sync::RwLock;
+use tracing::error;
+
+use crate::{api::server_server::FedDest, Config, Error};
+
+pub type WellKnownMap = HashMap<OwnedServerName, (FedDest, String)>;
+pub type TlsNameMap = HashMap<String, (Vec<IpAddr>, u16)>;
+
+pub struct Resolver {
+	inner: GaiResolver,
+	pub overrides: Arc<StdRwLock<TlsNameMap>>,
+	pub destinations: Arc<RwLock<WellKnownMap>>, // actual_destination, host
+	pub resolver: TokioAsyncResolver,
+}
+
+impl Resolver {
+	pub(crate) fn new(_config: &Config) -> Self {
+		Resolver {
+			inner: GaiResolver::new(),
+			overrides: Arc::new(StdRwLock::new(TlsNameMap::new())),
+			destinations: Arc::new(RwLock::new(WellKnownMap::new())),
+			resolver: TokioAsyncResolver::tokio_from_system_conf()
+				.map_err(|e| {
+					error!("Failed to set up trust dns resolver with system config: {}", e);
+					Error::bad_config("Failed to set up trust dns resolver with system config.")
+				})
+				.unwrap(),
+		}
+	}
+}
+
+impl Resolve for Resolver {
+	fn resolve(&self, name: Name) -> Resolving {
+		self.overrides
+			.read()
+			.unwrap()
+			.get(name.as_str())
+			.and_then(|(override_name, port)| {
+				override_name.first().map(|first_name| {
+					let x: Box<dyn Iterator<Item = SocketAddr> + Send> =
+						Box::new(iter::once(SocketAddr::new(*first_name, *port)));
+					let x: Resolving = Box::pin(future::ready(Ok(x)));
+					x
+				})
+			})
+			.unwrap_or_else(|| {
+				let this = &mut self.inner.clone();
+				Box::pin(HyperService::<Name>::call(this, name).map(|result| {
+					result
+						.map(|addrs| -> Addrs { Box::new(addrs) })
+						.map_err(|err| -> Box<dyn StdError + Send + Sync> { Box::new(err) })
+				}))
+			})
+	}
+}