rpc: add digest

easytier/src/proto/dns.rs

@@ -1,7 +1,21 @@
+use serde::Serialize;
+use sha2::{Digest, Sha256};
 use std::fmt::Display;
 
 include!(concat!(env!("OUT_DIR"), "/dns.rs"));
 
+pub trait DeterministicDigest: Serialize {
+    fn digest(&self) -> Vec<u8> {
+        let json = serde_json::to_vec(self).expect("failed to serialize the object to json");
+        let mut hasher = Sha256::new();
+        hasher.update(json);
+        hasher.finalize().to_vec()
+    }
+}
+
+impl DeterministicDigest for DnsConfigPb {}
+impl DeterministicDigest for ZoneConfigPb {}
+
 impl Display for ZoneConfigPb {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         writeln!(f, "; EasyTier Magic DNS zone file")?;