Implemented deserializer for InfoHash

src/tracker.rs

@@ -1,4 +1,5 @@
 use std;
+use serde;
 use binascii;
 
 use server::Events;
@@ -57,6 +58,38 @@ impl serde::ser::Serialize for InfoHash {
     }
 }
 
+struct InfoHashVisitor;
+
+impl<'v> serde::de::Visitor<'v> for InfoHashVisitor {
+    type Value = InfoHash;
+
+    fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(formatter, "a 40 character long hash")
+    }
+
+    fn visit_str<E: serde::de::Error>(self, v: &str) -> Result<Self::Value, E> {
+        if v.len() != 40 {
+            return Err(serde::de::Error::invalid_value(serde::de::Unexpected::Str(v), &"expected a 40 character long string"));
+        }
+
+        let mut res = InfoHash{
+            info_hash: [0u8; 20],
+        };
+
+        if let Err(_) = binascii::hex2bin(v.as_bytes(), &mut res.info_hash) {
+            return Err(serde::de::Error::invalid_value(serde::de::Unexpected::Str(v), &"expected a hexadecimal string"));
+        } else {
+            return Ok(res);
+        }
+    }
+}
+
+impl<'de> serde::de::Deserialize<'de> for InfoHash {
+    fn deserialize<D: serde::de::Deserializer<'de>>(des: D) -> Result<Self, D::Error> {
+        des.deserialize_str(InfoHashVisitor)
+    }
+}
+
 pub type PeerId = [u8; 20];
 
 #[derive(Serialize, Deserialize)]
@@ -283,4 +316,17 @@ mod tests {
     fn tracker_sync() {
         is_sync::<TorrentTracker>();
     }
+
+    #[test]
+    fn test_infohash_de() {
+        use serde_json;
+
+        let ih: InfoHash = [0u8, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1].into();
+
+        let serialized_ih = serde_json::to_string(&ih).unwrap();
+
+        let de_ih: InfoHash = serde_json::from_str(serialized_ih.as_str()).unwrap();
+
+        assert!(de_ih == ih);
+    }
 }