lighthouse/consensus/serde_utils/src/hex.rs
Michael Sproul f9d60f5436 VC: accept unknown fields in chain spec (#2277)
## Issue Addressed

Closes #2274

## Proposed Changes

* Modify the `YamlConfig` to collect unknown fields into an `extra_fields` map, instead of failing hard.
* Log a debug message if there are extra fields returned to the VC from one of its BNs.

This restores Lighthouse's compatibility with Teku beacon nodes (and therefore Infura)
2021-03-26 04:53:57 +00:00

82 lines
2.1 KiB
Rust

//! Provides utilities for parsing 0x-prefixed hex strings.
use serde::de::{self, Visitor};
use std::fmt;
/// Encode `data` as a 0x-prefixed hex string.
pub fn encode<T: AsRef<[u8]>>(data: T) -> String {
let hex = hex::encode(data);
let mut s = "0x".to_string();
s.push_str(hex.as_str());
s
}
/// Decode `data` from a 0x-prefixed hex string.
pub fn decode(s: &str) -> Result<Vec<u8>, String> {
if let Some(stripped) = s.strip_prefix("0x") {
hex::decode(stripped).map_err(|e| format!("invalid hex: {:?}", e))
} else {
Err("hex must have 0x prefix".to_string())
}
}
pub struct PrefixedHexVisitor;
impl<'de> Visitor<'de> for PrefixedHexVisitor {
type Value = Vec<u8>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a hex string with 0x prefix")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: de::Error,
{
if let Some(stripped) = value.strip_prefix("0x") {
Ok(hex::decode(stripped)
.map_err(|e| de::Error::custom(format!("invalid hex ({:?})", e)))?)
} else {
Err(de::Error::custom("missing 0x prefix"))
}
}
}
pub struct HexVisitor;
impl<'de> Visitor<'de> for HexVisitor {
type Value = Vec<u8>;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a hex string (irrelevant of prefix)")
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
where
E: de::Error,
{
hex::decode(value.trim_start_matches("0x"))
.map_err(|e| de::Error::custom(format!("invalid hex ({:?})", e)))
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn encoding() {
let bytes = vec![0, 255];
let hex = encode(&bytes);
assert_eq!(hex.as_str(), "0x00ff");
let bytes = vec![];
let hex = encode(&bytes);
assert_eq!(hex.as_str(), "0x");
let bytes = vec![1, 2, 3];
let hex = encode(&bytes);
assert_eq!(hex.as_str(), "0x010203");
}
}