support ipv6 connect

[sallyyu0]

There are places that connect() still uses string url stored in slots(ex: "redis://fd00:10:0:5:5861:50ff:fe00:85:6379") instead of ConnectionInfo. Please update those to use ConnectionInfo instead to avoid parse error. Below is an example for converting string to ConnectionInfo.

fn get_conn_info(redis_url: &str) -> Option<ConnectionInfo> {
    let v: Vec<&str> = redis_url.split("://").collect();
    if v.len() == 2 {
        let h: Vec<&str> = v[1].split(":").collect();
        let port: u16 = h[h.len() - 1].parse().unwrap();
        let (host, _) = v[1].split_at(v[1].len() - port.to_string().len() - 1);
        return Some(ConnectionInfo {
            addr: Box::new(ConnectionAddr::Tcp(host.to_string(), port)),
            db: 0,
            passwd: None,
        });
    } else {
        return None;
    }
}

[sallyyu0]

Maybe it's better to fix format "redis://{}:{}" to "redis://[{}]:{}" for IPv6 address as root cause.

[sallyyu0]

diff --git a/src/cluster.rs b/src/cluster.rs
index 0d74feb..5b67384 100644
--- a/src/cluster.rs
+++ b/src/cluster.rs
@@ -41,6 +41,8 @@
 use std::cell::RefCell;
 use std::collections::{BTreeMap, HashMap, HashSet};
 use std::iter::Iterator;
+use std::net::Ipv6Addr;
+use std::str::FromStr;
 use std::thread;
 use std::time::Duration;
 
@@ -262,7 +264,10 @@ impl ClusterConnection {
 
         for info in initial_nodes.iter() {
             let addr = match *info.addr {
-                ConnectionAddr::Tcp(ref host, port) => format!("redis://{}:{}", host, port),
+                ConnectionAddr::Tcp(ref host, port) => match Ipv6Addr::from_str(host) {
+                    Ok(_) => format!("redis://[{}]:{}", host, port),
+                    Err(_) => format!("redis://{}:{}", host, port),
+                },
                 _ => panic!("No reach."),
             };
 
@@ -314,12 +319,11 @@ impl ClusterConnection {
                             continue;
                         }
                     }
-
-                    if let Ok(mut conn) =
-                        connect(addr.as_ref(), self.readonly, self.password.clone())
-                    {
-                        if check_connection(&mut conn) {
-                            new_connections.insert(addr.to_string(), conn);
+                    if let Some(info) = get_conn_info(addr.as_ref()) {
+                        if let Ok(mut conn) = connect(info, self.readonly, self.password.clone()) {
+                            if check_connection(&mut conn) {
+                                new_connections.insert(addr.to_string(), conn);
+                            }
                         }
                     }
                 }
@@ -413,8 +417,15 @@ impl ClusterConnection {
         } else {
             // Create new connection.
             // TODO: error handling
-            let conn = connect(addr, self.readonly, self.password.clone())?;
-            Ok(connections.entry(addr.to_string()).or_insert(conn))
+            if let Some(info) = get_conn_info(addr) {
+                let conn = connect(info, self.readonly, self.password.clone())?;
+                Ok(connections.entry(addr.to_string()).or_insert(conn))
+            } else {
+                Err(RedisError::from((
+                    ErrorKind::ExecAbortError,
+                    "Cannot translate url to ConnectionInfo.",
+                )))
+            }
         }
     }
 
@@ -825,7 +836,10 @@ fn get_slots(connection: &mut Connection) -> RedisResult<Vec<Slot>> {
                         } else {
                             return None;
                         };
-                        Some(format!("redis://{}:{}", ip, port))
+                        match Ipv6Addr::from_str(&ip) {
+                            Ok(_) => Some(format!("redis://[{}]:{}", ip, port)),
+                            Err(_) => Some(format!("redis://{}:{}", ip, port)),
+                        }
                     } else {
                         None
                     }
@@ -848,7 +862,27 @@ fn get_slots(connection: &mut Connection) -> RedisResult<Vec<Slot>> {
 
     Ok(result)
 }
-
+// translate redis_url to ConnectionInfo
+fn get_conn_info(redis_url: &str) -> Option<ConnectionInfo> {
+    let v: Vec<&str> = redis_url.split("://").collect();
+    if v.len() == 2 {
+        let h: Vec<&str> = v[1].split(":").collect();
+        let port: u16 = h[h.len() - 1].parse().unwrap();
+        let (host, _) = v[1].split_at(v[1].len() - port.to_string().len() - 1);
+        return Some(ConnectionInfo {
+            addr: Box::new(ConnectionAddr::Tcp(
+                host.trim_start_matches('[')
+                    .trim_end_matches(']')
+                    .to_string(),
+                port,
+            )),
+            db: 0,
+            passwd: None,
+        });
+    } else {
+        return None;
+    }
+}
 #[cfg(test)]

[vstakhov]

Is there any workaround for this issue? I have tried to specify IPv6 address in many ways: as [::1]:6379, as ::1:6379, parse it to url::Url (which worked for [::1]:6379 but still failed with redis-rs with the following error: failed to lookup address information: nodename nor servname provided, or not known).

I'd be happy to use any workaround for IPv6 addresses in fact.

[djc]

Should be fixed with #679.