refactor(runtime): return iterator from resolve_addr (#8891)

3 files changed, 76 insertions, 40 deletions

diff --git a/runtime/ops/net.rs b/runtime/ops/net.rs
index a4bda585b..1ff1e3511 100644
--- a/runtime/ops/net.rs
+++ b/runtime/ops/net.rs
@@ -202,7 +202,10 @@ async fn op_datagram_send(
         s.borrow::<Permissions>()
           .check_net(&args.hostname, args.port)?;
       }
-      let addr = resolve_addr(&args.hostname, args.port).await?;
+      let addr = resolve_addr(&args.hostname, args.port)
+        .await?
+        .next()
+        .ok_or_else(|| generic_error("No resolved address found"))?;
 
       let resource = state
         .borrow_mut()
@@ -267,7 +270,10 @@ async fn op_connect(
           .borrow::<Permissions>()
           .check_net(&args.hostname, args.port)?;
       }
-      let addr = resolve_addr(&args.hostname, args.port).await?;
+      let addr = resolve_addr(&args.hostname, args.port)
+        .await?
+        .next()
+        .ok_or_else(|| generic_error("No resolved address found"))?;
       let tcp_stream = TcpStream::connect(&addr).await?;
       let local_addr = tcp_stream.local_addr()?;
       let remote_addr = tcp_stream.peer_addr()?;
@@ -469,7 +475,9 @@ fn op_listen(
         }
         permissions.check_net(&args.hostname, args.port)?;
       }
-      let addr = resolve_addr_sync(&args.hostname, args.port)?;
+      let addr = resolve_addr_sync(&args.hostname, args.port)?
+        .next()
+        .ok_or_else(|| generic_error("No resolved address found"))?;
       let (rid, local_addr) = if transport == "tcp" {
         listen_tcp(state, addr)?
       } else {
diff --git a/runtime/ops/tls.rs b/runtime/ops/tls.rs
index 0630747ed..fb8b08f00 100644
--- a/runtime/ops/tls.rs
+++ b/runtime/ops/tls.rs
@@ -8,6 +8,7 @@ use crate::resolve_addr::resolve_addr_sync;
 use deno_core::error::bad_resource;
 use deno_core::error::bad_resource_id;
 use deno_core::error::custom_error;
+use deno_core::error::generic_error;
 use deno_core::error::AnyError;
 use deno_core::serde_json;
 use deno_core::serde_json::json;
@@ -156,7 +157,10 @@ async fn op_connect_tls(
     domain.push_str("localhost");
   }
 
-  let addr = resolve_addr(&args.hostname, args.port).await?;
+  let addr = resolve_addr(&args.hostname, args.port)
+    .await?
+    .next()
+    .ok_or_else(|| generic_error("No resolved address found"))?;
   let tcp_stream = TcpStream::connect(&addr).await?;
   let local_addr = tcp_stream.local_addr()?;
   let remote_addr = tcp_stream.peer_addr()?;
@@ -295,7 +299,9 @@ fn op_listen_tls(
     .set_single_cert(load_certs(&cert_file)?, load_keys(&key_file)?.remove(0))
     .expect("invalid key or certificate");
   let tls_acceptor = TlsAcceptor::from(Arc::new(config));
-  let addr = resolve_addr_sync(&args.hostname, args.port)?;
+  let addr = resolve_addr_sync(&args.hostname, args.port)?
+    .next()
+    .ok_or_else(|| generic_error("No resolved address found"))?;
   let std_listener = std::net::TcpListener::bind(&addr)?;
   let listener = TcpListener::from_std(std_listener)?;
   let local_addr = listener.local_addr()?;
diff --git a/runtime/resolve_addr.rs b/runtime/resolve_addr.rs
index d4f500802..72c324036 100644
--- a/runtime/resolve_addr.rs
+++ b/runtime/resolve_addr.rs
@@ -1,7 +1,6 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 
 use deno_core::error::AnyError;
-use deno_core::error::Context;
 use std::net::SocketAddr;
 use std::net::ToSocketAddrs;
 use tokio::net::lookup_host;
@@ -10,24 +9,20 @@ use tokio::net::lookup_host;
 pub async fn resolve_addr(
   hostname: &str,
   port: u16,
-) -> Result<SocketAddr, AnyError> {
+) -> Result<impl Iterator<Item = SocketAddr> + '_, AnyError> {
   let addr_port_pair = make_addr_port_pair(hostname, port);
-  lookup_host(addr_port_pair)
-    .await?
-    .next()
-    .context("No resolved address found")
+  let result = lookup_host(addr_port_pair).await?;
+  Ok(result)
 }
 
 /// Resolve network address *synchronously*.
 pub fn resolve_addr_sync(
   hostname: &str,
   port: u16,
-) -> Result<SocketAddr, AnyError> {
+) -> Result<impl Iterator<Item = SocketAddr>, AnyError> {
   let addr_port_pair = make_addr_port_pair(hostname, port);
-  addr_port_pair
-    .to_socket_addrs()?
-    .next()
-    .context("No resolved address found")
+  let result = addr_port_pair.to_socket_addrs()?;
+  Ok(result)
 }
 
 fn make_addr_port_pair(hostname: &str, port: u16) -> (&str, u16) {
@@ -52,37 +47,52 @@ mod tests {
 
   #[tokio::test]
   async fn resolve_addr1() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 80));
-    let actual = resolve_addr("127.0.0.1", 80).await.unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(127, 0, 0, 1),
+      80,
+    ))];
+    let actual = resolve_addr("127.0.0.1", 80)
+      .await
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[tokio::test]
   async fn resolve_addr2() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(0, 0, 0, 0), 80));
-    let actual = resolve_addr("", 80).await.unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(0, 0, 0, 0),
+      80,
+    ))];
+    let actual = resolve_addr("", 80).await.unwrap().collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[tokio::test]
   async fn resolve_addr3() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(192, 0, 2, 1), 25));
-    let actual = resolve_addr("192.0.2.1", 25).await.unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(192, 0, 2, 1),
+      25,
+    ))];
+    let actual = resolve_addr("192.0.2.1", 25)
+      .await
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[tokio::test]
   async fn resolve_addr_ipv6() {
-    let expected = SocketAddr::V6(SocketAddrV6::new(
+    let expected = vec![SocketAddr::V6(SocketAddrV6::new(
       Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1),
       8080,
       0,
       0,
-    ));
-    let actual = resolve_addr("[2001:db8::1]", 8080).await.unwrap();
+    ))];
+    let actual = resolve_addr("[2001:db8::1]", 8080)
+      .await
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
@@ -93,37 +103,49 @@ mod tests {
 
   #[test]
   fn resolve_addr_sync1() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 80));
-    let actual = resolve_addr_sync("127.0.0.1", 80).unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(127, 0, 0, 1),
+      80,
+    ))];
+    let actual = resolve_addr_sync("127.0.0.1", 80)
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[test]
   fn resolve_addr_sync2() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(0, 0, 0, 0), 80));
-    let actual = resolve_addr_sync("", 80).unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(0, 0, 0, 0),
+      80,
+    ))];
+    let actual = resolve_addr_sync("", 80).unwrap().collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[test]
   fn resolve_addr_sync3() {
-    let expected =
-      SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(192, 0, 2, 1), 25));
-    let actual = resolve_addr_sync("192.0.2.1", 25).unwrap();
+    let expected = vec![SocketAddr::V4(SocketAddrV4::new(
+      Ipv4Addr::new(192, 0, 2, 1),
+      25,
+    ))];
+    let actual = resolve_addr_sync("192.0.2.1", 25)
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }
 
   #[test]
   fn resolve_addr_sync_ipv6() {
-    let expected = SocketAddr::V6(SocketAddrV6::new(
+    let expected = vec![SocketAddr::V6(SocketAddrV6::new(
       Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1),
       8080,
       0,
       0,
-    ));
-    let actual = resolve_addr_sync("[2001:db8::1]", 8080).unwrap();
+    ))];
+    let actual = resolve_addr_sync("[2001:db8::1]", 8080)
+      .unwrap()
+      .collect::<Vec<_>>();
     assert_eq!(actual, expected);
   }