feat: derive serde for header (#902)

crates/consensus/src/header.rs

@@ -22,6 +22,8 @@ pub const EMPTY_ROOT_HASH: B256 =
 
 /// Ethereum Block header
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", serde(rename_all = "camelCase"))]
 pub struct Header {
     /// The Keccak 256-bit hash of the parent
     /// block’s header, in its entirety; formally Hp.
@@ -42,6 +44,7 @@ pub struct Header {
     pub receipts_root: B256,
     /// The Keccak 256-bit hash of the withdrawals list portion of this block.
     /// <https://eips.ethereum.org/EIPS/eip-4895>
+    #[cfg_attr(feature = "serde", serde(default, skip_serializing_if = "Option::is_none"))]
     pub withdrawals_root: Option<B256>,
     /// The Bloom filter composed from indexable information (logger address and log topics)
     /// contained in each log entry from the receipt of each transaction in the transactions list;
@@ -52,13 +55,17 @@ pub struct Header {
     pub difficulty: U256,
     /// A scalar value equal to the number of ancestor blocks. The genesis block has a number of
     /// zero; formally Hi.
+    #[cfg_attr(feature = "serde", serde(with = "alloy_serde::quantity"))]
     pub number: BlockNumber,
     /// A scalar value equal to the current limit of gas expenditure per block; formally Hl.
+    #[cfg_attr(feature = "serde", serde(with = "alloy_serde::quantity"))]
     pub gas_limit: u128,
     /// A scalar value equal to the total gas used in transactions in this block; formally Hg.
+    #[cfg_attr(feature = "serde", serde(with = "alloy_serde::quantity"))]
     pub gas_used: u128,
     /// A scalar value equal to the reasonable output of Unix’s time() at this block’s inception;
     /// formally Hs.
+    #[cfg_attr(feature = "serde", serde(with = "alloy_serde::quantity"))]
     pub timestamp: u64,
     /// A 256-bit hash which, combined with the
     /// nonce, proves that a sufficient amount of computation has been carried out on this block;
@@ -73,13 +80,37 @@ pub struct Header {
     /// The algorithm results in the base fee per gas increasing when blocks are
     /// above the gas target, and decreasing when blocks are below the gas target. The base fee per
     /// gas is burned.
+    #[cfg_attr(
+        feature = "serde",
+        serde(
+            default,
+            with = "alloy_serde::quantity::opt",
+            skip_serializing_if = "Option::is_none"
+        )
+    )]
     pub base_fee_per_gas: Option<u128>,
     /// The total amount of blob gas consumed by the transactions within the block, added in
     /// EIP-4844.
+    #[cfg_attr(
+        feature = "serde",
+        serde(
+            default,
+            with = "alloy_serde::quantity::opt",
+            skip_serializing_if = "Option::is_none"
+        )
+    )]
     pub blob_gas_used: Option<u128>,
     /// A running total of blob gas consumed in excess of the target, prior to the block. Blocks
     /// with above-target blob gas consumption increase this value, blocks with below-target blob
     /// gas consumption decrease it (bounded at 0). This was added in EIP-4844.
+    #[cfg_attr(
+        feature = "serde",
+        serde(
+            default,
+            with = "alloy_serde::quantity::opt",
+            skip_serializing_if = "Option::is_none"
+        )
+    )]
     pub excess_blob_gas: Option<u128>,
     /// The hash of the parent beacon block's root is included in execution blocks, as proposed by
     /// EIP-4788.
@@ -88,11 +119,13 @@ pub struct Header {
     /// and more.
     ///
     /// The beacon roots contract handles root storage, enhancing Ethereum's functionalities.
+    #[cfg_attr(feature = "serde", serde(default, skip_serializing_if = "Option::is_none"))]
     pub parent_beacon_block_root: Option<B256>,
     /// The Keccak 256-bit hash of the root node of the trie structure populated with each
     /// [EIP-7685] request in the block body.
     ///
     /// [EIP-7685]: https://eips.ethereum.org/EIPS/eip-7685
+    #[cfg_attr(feature = "serde", serde(default, skip_serializing_if = "Option::is_none"))]
     pub requests_root: Option<B256>,
     /// An arbitrary byte array containing data relevant to this block. This must be 32 bytes or
     /// fewer; formally Hx.
@@ -492,3 +525,25 @@ impl Decodable for Header {
         Ok(this)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[cfg(feature = "serde")]
+    #[test]
+    fn header_serde() {
+        let raw = r#"{"parentHash":"0x0000000000000000000000000000000000000000000000000000000000000000","ommersHash":"0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347","beneficiary":"0x0000000000000000000000000000000000000000","stateRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","transactionsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","receiptsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","withdrawalsRoot":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","logsBloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","difficulty":"0x0","number":"0x0","gasLimit":"0x0","gasUsed":"0x0","timestamp":"0x0","mixHash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x0000000000000000","baseFeePerGas":"0x1","extraData":"0x"}"#;
+        let header = Header {
+            base_fee_per_gas: Some(1),
+            withdrawals_root: Some(EMPTY_ROOT_HASH),
+            ..Default::default()
+        };
+
+        let json = serde_json::to_string(&header).unwrap();
+        assert_eq!(json, raw);
+
+        let decoded: Header = serde_json::from_str(&json).unwrap();
+        assert_eq!(decoded, header);
+    }
+}