Add no responders handling

nats-io · May 25, 2022 · a3c370c · a3c370c
1 parent c279362
commit a3c370c
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Showing 3 changed files with 76 additions and 18 deletions.
diff --git a/async-nats/src/connection.rs b/async-nats/src/connection.rs
@@ -1,4 +1,4 @@
-use std::collections::HashSet;
+use std::num::{NonZeroU16, NonZeroU8};
 use std::str::FromStr;
 
 use subslice::SubsliceExt;
@@ -114,6 +114,8 @@ impl Connection {
                         headers: None,
                         subject,
                         payload,
+                        status: None,
+                        description: None,
                     }));
                 }
             }
@@ -203,20 +205,31 @@ impl Connection {
                     }
 
                     let mut headers = HeaderMap::new();
+                    let mut maybe_status: Option<NonZeroU16> = None;
+                    let mut maybe_description: Option<String> = None;
                     if let Some(slice) = version_line.get("NATS/1.0".len()..).map(|s| s.trim()) {
                         match slice.split_once(' ') {
                             Some((status, description)) => {
                                 if !status.is_empty() {
-                                    headers.append("Status", status.trim().try_into().unwrap());
+                                    maybe_status = Some(status.trim().parse().map_err(|_| {
+                                        std::io::Error::new(
+                                            io::ErrorKind::Other,
+                                            "could not covert Description header into header value",
+                                        )
+                                    })?);
                                 }
                                 if !description.is_empty() {
-                                    headers
-                                        .append("Description", status.trim().try_into().unwrap());
+                                    maybe_description = Some(description.trim().to_string());
                                 }
                             }
                             None => {
                                 if !slice.is_empty() {
-                                    headers.append("Status", slice.try_into().unwrap());
+                                    maybe_status = Some(slice.trim().parse().map_err(|_| {
+                                        std::io::Error::new(
+                                            io::ErrorKind::Other,
+                                            "could not covert Description header into header value",
+                                        )
+                                    })?);
                                 }
                             }
                         }
@@ -251,6 +264,8 @@ impl Connection {
                         subject,
                         headers: Some(headers),
                         payload,
+                        status: maybe_status,
+                        description: maybe_description,
                     }));
                 }
             }
@@ -524,6 +539,8 @@ mod read_op {
                 reply: None,
                 headers: None,
                 payload: "Hello World".into(),
+                status: None,
+                description: None,
             })
         );
 
@@ -541,6 +558,8 @@ mod read_op {
                 reply: Some("INBOX.34".into()),
                 headers: None,
                 payload: "Hello World".into(),
+                status: None,
+                description: None,
             })
         );
 
@@ -565,6 +584,8 @@ mod read_op {
                     "X".parse().unwrap()
                 )])),
                 payload: "Hello World".into(),
+                status: None,
+                description: None,
             })
         );
     }
@@ -780,7 +801,7 @@ mod write_op {
                 pass: None,
                 auth_token: None,
                 headers: false,
-                no_responders: true,
+                no_responders: false,
             }))
             .await
             .unwrap();
@@ -789,7 +810,7 @@ mod write_op {
         reader.read_line(&mut buffer).await.unwrap();
         assert_eq!(
             buffer,
-            "CONNECT {\"verbose\":false,\"pedantic\":false,\"jwt\":null,\"nkey\":null,\"sig\":null,\"name\":null,\"echo\":false,\"lang\":\"Rust\",\"version\":\"1.0.0\",\"protocol\":1,\"tls_required\":false,\"user\":null,\"pass\":null,\"auth_token\":null,\"headers\":false,\"no_responders\":true}\r\n"
+            "CONNECT {\"verbose\":false,\"pedantic\":false,\"jwt\":null,\"nkey\":null,\"sig\":null,\"name\":null,\"echo\":false,\"lang\":\"Rust\",\"version\":\"1.0.0\",\"protocol\":1,\"tls_required\":false,\"user\":null,\"pass\":null,\"auth_token\":null,\"headers\":false,\"no_responders\":false}\r\n"
         );
     }
 }
diff --git a/async-nats/src/lib.rs b/async-nats/src/lib.rs
@@ -111,6 +111,9 @@ use std::cmp;
 use std::collections::HashMap;
 use std::iter;
 use std::net::{SocketAddr, ToSocketAddrs};
+use std::num::NonZeroU128;
+use std::num::NonZeroU16;
+use std::num::NonZeroU8;
 use std::option;
 use std::pin::Pin;
 use std::slice;
@@ -223,6 +226,8 @@ pub(crate) enum ServerOp {
         reply: Option<String>,
         payload: Bytes,
         headers: Option<HeaderMap>,
+        status: Option<NonZeroU16>,
+        description: Option<String>,
     },
 }
 
@@ -507,13 +512,17 @@ impl ConnectionHandler {
                 reply,
                 payload,
                 headers,
+                status,
+                description,
             } => {
                 if let Some(subscription) = self.subscriptions.get_mut(&sid) {
                     let message = Message {
                         subject,
                         reply,
                         payload,
                         headers,
+                        status,
+                        description,
                     };
 
                     // if the channel for subscription was dropped, remove the
@@ -791,7 +800,15 @@ impl Client {
         self.publish_with_reply(subject, inbox, payload).await?;
         self.flush().await?;
         match sub.next().await {
-            Some(message) => Ok(message),
+            Some(message) => {
+                if message.is_no_responders() {
+                    return Err(Box::new(std::io::Error::new(
+                        ErrorKind::NotFound,
+                        "nats: no responders",
+                    )));
+                }
+                Ok(message)
+            }
             None => Err(Box::new(io::Error::new(
                 ErrorKind::BrokenPipe,
                 "did not receive any message",
@@ -811,7 +828,15 @@ impl Client {
             .await?;
         self.flush().await?;
         match sub.next().await {
-            Some(message) => Ok(message),
+            Some(message) => {
+                if message.is_no_responders() {
+                    return Err(Box::new(std::io::Error::new(
+                        ErrorKind::NotFound,
+                        "nats: no responders",
+                    )));
+                }
+                Ok(message)
+            }
             None => Err(Box::new(io::Error::new(
                 ErrorKind::BrokenPipe,
                 "did not receive any message",
@@ -1052,8 +1077,24 @@ pub struct Message {
     pub reply: Option<String>,
     pub payload: Bytes,
     pub headers: Option<HeaderMap>,
+    status: Option<NonZeroU16>,
+    description: Option<String>,
+}
+
+impl Message {
+    fn is_no_responders(&self) -> bool {
+        if !self.payload.is_empty() {
+            return false;
+        }
+        if self.status == NonZeroU16::new(NO_RESPONDERS) {
+            return true;
+        }
+        false
+    }
 }
 
+const NO_RESPONDERS: u16 = 503;
+
 /// Retrieves messages from given `subscription` created by [Client::subscribe].
 ///
 /// Implements [futures::stream::Stream] for ergonomic async message processing.

diff --git a/async-nats/tests/client_tests.rs b/async-nats/tests/client_tests.rs
@@ -12,7 +12,7 @@
 // limitations under the License.
 
 mod client {
-    use async_nats::{ConnectOptions, ServerError};
+    use async_nats::{ConnectOptions, Message, ServerError};
     use bytes::Bytes;
     use futures::future::join_all;
     use futures::stream::StreamExt;
@@ -198,17 +198,13 @@ mod client {
         let server = nats_server::run_basic_server();
         let client = async_nats::connect(server.client_url()).await.unwrap();
 
-        let resp = tokio::time::timeout(
-            tokio::time::Duration::from_millis(500),
+        tokio::time::timeout(
+            tokio::time::Duration::from_millis(300),
             client.request("test".into(), "request".into()),
         )
         .await
-        .unwrap();
-        println!(
-            "headers: {:?}",
-            resp.unwrap().headers.unwrap().get("Status").unwrap()
-        );
-        // assert_eq!(resp.unwrap().payload, Bytes::from("reply"));
+        .unwrap()
+        .unwrap_err();
     }
 
     #[tokio::test]