src/lib: Add Multiaddr::protocol_stack

src/lib.rs

@@ -191,6 +191,10 @@ impl Multiaddr {
         }
         self.bytes[(n - m)..] == other.bytes[..]
     }
+
+    pub fn protocol_stack(&self) -> ProtoStackIter {
+        ProtoStackIter{ parts: self.iter() }
+    }
 }
 
 impl fmt::Debug for Multiaddr {
@@ -293,6 +297,17 @@ impl<'a> Iterator for Iter<'a> {
     }
 }
 
+pub struct ProtoStackIter<'a>{
+    parts: Iter<'a>
+}
+
+impl<'a> Iterator for ProtoStackIter<'a> {
+    type Item =  &'static str;
+    fn next(&mut self) -> Option<Self::Item> {
+        self.parts.next().map(|p|p.tag())
+    }
+}
+
 impl<'a> From<Protocol<'a>> for Multiaddr {
     fn from(p: Protocol<'a>) -> Multiaddr {
         let mut w = Vec::new();

src/protocol.rs

@@ -510,6 +510,44 @@ impl<'a> Protocol<'a> {
             Wss(cow) => Wss(Cow::Owned(cow.into_owned())),
         }
     }
+
+    pub fn tag(&self) -> &'static str {
+        use self::Protocol::*;
+        match self {
+            Dccp(_) => "dccp",
+            Dns(_) => "dns",
+            Dns4(_) => "dns4",
+            Dns6(_) => "dns6",
+            Dnsaddr(_) => "dnsaddr",
+            Http => "http",
+            Https => "https",
+            Ip4(_) => "ip4",
+            Ip6(_) => "ip6",
+            P2pWebRtcDirect => "p2p-webrtc-direct",
+            P2pWebRtcStar => "p2p-webrtc-star",
+            WebRTC => "webrtc",
+            Certhash(_) => "certhash",
+            P2pWebSocketStar => "p2p-websocket-star",
+            Memory(_) => "memory",
+            Onion(_, _) => "onion",
+            Onion3(_) => "onion3",
+            P2p(_) =>"p2p",
+            P2pCircuit => "p2p-circuit",
+            Quic => "quic",
+            Sctp(_) => "sctp",
+            Tcp(_) => "tcp",
+            Tls => "tls",
+            Noise => "noise",
+            Udp(_) => "udp",
+            Udt => "udt",
+            Unix(_) => "unix",
+            Utp => "utp",
+            Ws(ref s)  if s == "/" =>  "ws",
+            Ws(_) => "x-parity-ws",
+            Wss(ref s)  if s == "/" =>  "wss",
+            Wss(_) => "x-parity-wss",
+        }
+    }
 }
 
 impl<'a> fmt::Display for Protocol<'a> {

tests/lib.rs

@@ -1,3 +1,5 @@
+extern crate core;
+
 use data_encoding::HEXUPPER;
 use multiaddr::*;
 use multihash::Multihash;
@@ -527,3 +529,79 @@ fn unknown_protocol_string() {
         },
     }
 }
+
+#[test]
+fn protocol_stack() {
+    let addresses = [
+        "/ip4/0.0.0.0",
+        "/ip6/::1",
+        "/ip6/2601:9:4f81:9700:803e:ca65:66e8:c21",
+        "/udp/0",
+        "/tcp/0",
+        "/sctp/0",
+        "/udp/1234",
+        "/tcp/1234",
+        "/sctp/1234",
+        "/udp/65535",
+        "/tcp/65535",
+        "/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/udp/1234/sctp/1234",
+        "/udp/1234/udt",
+        "/udp/1234/utp",
+        "/tcp/1234/http",
+        "/tcp/1234/tls/http",
+        "/tcp/1234/https",
+        "/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC/tcp/1234",
+        "/ip4/127.0.0.1/udp/1234",
+        "/ip4/127.0.0.1/udp/0",
+        "/ip4/127.0.0.1/tcp/1234",
+        "/ip4/127.0.0.1/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/ip4/127.0.0.1/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC/tcp/1234",
+        "/ip6/2001:8a0:7ac5:4201:3ac9:86ff:fe31:7095/tcp/8000/ws/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/p2p-webrtc-star/ip4/127.0.0.1/tcp/9090/ws/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/ip6/2001:8a0:7ac5:4201:3ac9:86ff:fe31:7095/tcp/8000/wss/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/ip4/127.0.0.1/tcp/9090/p2p-circuit/p2p/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
+        "/onion/aaimaq4ygg2iegci:80",
+        "/dnsaddr/sjc-1.bootstrap.libp2p.io",
+        "/dnsaddr/sjc-1.bootstrap.libp2p.io/tcp/1234/p2p/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN",
+        "/ip4/127.0.0.1/tcp/127/ws",
+        "/ip4/127.0.0.1/tcp/127/tls",
+        "/ip4/127.0.0.1/tcp/127/tls/ws",
+        "/ip4/127.0.0.1/tcp/127/noise",
+        "/ip4/127.0.0.1/udp/1234/webrtc",
+    ];
+    let argless = std::collections::HashSet::from([
+        "http",
+        "https",
+        "noise",
+        "p2p-circuit",
+        "p2p-webrtc-direct",
+        "p2p-webrtc-star",
+        "p2p-websocket-star",
+        "quic",
+        "tls",
+        "udt",
+        "utp",
+        "webrtc",
+        "ws",
+        "wss",
+    ]);
+    for addr_str in addresses {
+        let ma = Multiaddr::from_str(addr_str).expect("These are supposed to be valid multiaddrs");
+        let ps: Vec<&str> = ma.protocol_stack().collect();
+        let mut toks: Vec<&str> = addr_str.split("/").collect();
+        assert_eq!("", toks[0]);
+        toks.remove(0);
+        let mut i = 0;
+        while i < toks.len() {
+            let proto_tag = toks[i];
+            i += 1;
+            if argless.contains(proto_tag) {
+                //skip
+            } else {
+                toks.remove(i);
+            }
+        }
+        assert_eq!(ps, toks);
+    }
+}