1  use std::borrow::Cow;
 2  
 3  use hex::{FromHex, ToHex};
 4  use serde::de::Error;
 5  use serde::{Deserialize, Serializer};
 6  
 7  /// Serialize a `&[u8]` to a hex String
 8  pub fn serialize<S>(data: &[u8], serializer: S) -> Result<S::Ok, S::Error>
 9  where
10      S: Serializer,
11  {
12      let hex: String = data.encode_hex();
13      serializer.serialize_str(&hex)
14  }
15  
16  /// Deserialize a hex String to a `Vec<u8>`
17  pub fn deserialize<'de, D: serde::Deserializer<'de>>(d: D) -> Result<Vec<u8>, D::Error> {
18      let hex_bytes: Cow<'de, str> = Deserialize::deserialize(d)?;
19      Vec::from_hex(hex_bytes.as_ref()).map_err(|_| D::Error::custom("invalid hex"))
20  }
21  
22  mod tests {
23      use serde::{Deserialize, Serialize};
24  
25      #[derive(Serialize, Deserialize, PartialEq, Debug)]
26      struct Data {
27          #[serde(with = "fedimint_core::hex::serde")]
28          inner: Vec<u8>,
29      }
30  
31      #[test]
32      fn hex_serialize() {
33          let data = Data {
34              inner: vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16],
35          };
36          let json = serde_json::to_string(&data).unwrap();
37  
38          assert_eq!(json, r#"{"inner":"000102030405060708090a0b0c0d0e0f10"}"#);
39      }
40  
41      #[test]
42      fn hex_deserialize() {
43          let json = r#"{"inner":"000102030405060708090a0b0c0d0e0f10"}"#;
44          let data: Data = serde_json::from_str(json).unwrap();
45  
46          assert_eq!(
47              data,
48              Data {
49                  inner: vec![0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]
50              }
51          );
52      }
53  }