feat: allow to connect via node id only

Author: Frando

iroh-net/src/magic_endpoint.rs

@@ -442,23 +442,8 @@ impl MagicEndpoint {
         node_id: &PublicKey,
         alpn: &[u8],
     ) -> Result<quinn::Connection> {
-        let addr = match self.msock.get_mapping_addr(node_id).await {
-            Some(addr) => addr,
-            None => {
-                let info = self.resolve(node_id).await?;
-                let peer_addr = NodeAddr {
-                    node_id: *node_id,
-                    info,
-                };
-                self.add_node_addr(peer_addr)?;
-                self.msock.get_mapping_addr(node_id).await.ok_or_else(|| {
-                    anyhow!("Failed to retrieve the mapped address from the magic socket. Unable to dial node {node_id:?}")
-                })?
-            }
-        };
-
-        debug!("connecting to {}: (via {})", node_id, addr);
-        self.connect_inner(node_id, alpn, addr).await
+        let addr = NodeAddr::new(*node_id);
+        self.connect(addr, alpn).await
     }
 
     /// Connect to a remote endpoint.
@@ -468,21 +453,42 @@ impl MagicEndpoint {
     /// connection without involving a DERP server. If no addresses are specified, the endpoint
     /// will try to dial the peer through the configured DERP servers.
     ///
-    /// If the `derp_url` is not `None` and the configured DERP servers do not include a DERP node from the given `derp_url`, it will error.
+    /// If the `derp_url` is not `None` and the configured DERP servers do not include a DERP node from the given `derp_url`,
+    /// it will use the configures [`Discovery`] service to retrieve DERP or direct addresses. If
+    /// this fails to return any info, it will error.
     ///
     /// If no UDP addresses and no DERP Url is provided, it will error.
+    //
+    // TODO: We should try to use the discovery service even if direct or derp addresses are
+    // provided.
     pub async fn connect(&self, node_addr: NodeAddr, alpn: &[u8]) -> Result<quinn::Connection> {
-        self.add_node_addr(node_addr.clone())?;
+        if !node_addr.info.is_empty() {
+            self.add_node_addr(node_addr.clone())?;
+        }
 
         let NodeAddr { node_id, info } = node_addr;
-        let addr = self.msock.get_mapping_addr(&node_id).await;
-        let Some(addr) = addr else {
-            return Err(match (info.direct_addresses.is_empty(), info.derp_url) {
-                (true, None) => {
-                    anyhow!("No UDP addresses or DERP Url provided. Unable to dial node {node_id:?}")
+
+        let addr = match self.msock.get_mapping_addr(&node_id).await {
+            Some(addr) => addr,
+            None => {
+                // Try to resolve the node address through the configured discovery service
+                let discovery = self.resolve(&node_id).await;
+                match discovery {
+                    Ok(info) if !info.is_empty() => {
+                        let node_addr = NodeAddr { node_id, info };
+                        self.add_node_addr(node_addr)?;
+                        self.msock.get_mapping_addr(&node_id).await.ok_or_else(|| {
+                            anyhow!("Failed to retrieve the mapped address from the magic socket. Unable to dial node {node_id:?}")
+                        })?
+                    }
+                    Ok(_info) => {
+                        return Err(anyhow!("Failed to discover Derp or direct adddresses for node {node_id:?}, unable to dial"));
+                    }
+                    Err(_err) => {
+                        return Err(anyhow!("Failed to discover Derp or direct adddresses for node {node_id:?}, unable to dial"));
+                    }
                 }
-                _ => anyhow!("Failed to retrieve the mapped address from the magic socket. Unable to dial node {node_id:?}")
-            });
+            }
         };
 
         debug!(

iroh/src/commands/blob.rs

@@ -199,11 +199,6 @@ impl BlobCommands {
                     return Err(anyhow::anyhow!("The input arguments refer to a collection of blobs and output is set to STDOUT. Only single blobs may be passed in this case."));
                 }
 
-                if node_addr.info.is_empty() {
-                    return Err(anyhow::anyhow!(
-                        "no Derp url provided and no direct addresses provided"
-                    ));
-                }
                 let tag = match tag {
                     Some(tag) => SetTagOption::Named(Tag::from(tag)),
                     None => SetTagOption::Auto,