Rework light client (#1475)

* WIP second pass over light client code for simpler API * First pass new light client * pub(crate) LightClientRpc::new_raw(), and fmt * Update examples and add back a way to configure boot nodes and fetch chainspec from a URL * Fix light client examples * remove unused deps and tidy lightclient feature flags * fix wasm error * LightClientRpc can be cloned * update light client tests * Other small fixes * exclude mod unless jsonrpsee * Fix wasm-lightclient-tests * add back docsrs bit and web+native feature flag compile error * update book and light client example names * fix docs
2026-06-13 08:11:04 +00:00 · 2024-03-15 15:21:06 +00:00
parent 4831f816f2
commit b069c4425a
32 changed files with 1236 additions and 1590 deletions
@@ -0,0 +1,71 @@
+// Copyright 2019-2023 Parity Technologies (UK) Ltd.
+// This file is dual-licensed as Apache-2.0 or GPL-3.0.
+// see LICENSE for license details.
+
+use serde_json::Value;
+use std::borrow::Cow;
+
+/// Something went wrong building chain config.
+#[non_exhaustive]
+#[derive(thiserror::Error, Debug)]
+pub enum ChainConfigError {
+    /// The provided chain spec is the wrong shape.
+    #[error("Invalid chain spec format")]
+    InvalidSpecFormat,
+}
+
+/// Configuration to connect to a chain.
+pub struct ChainConfig<'a> {
+    // The chain spec to use.
+    chain_spec: Cow<'a, str>,
+}
+
+impl<'a> From<&'a str> for ChainConfig<'a> {
+    fn from(chain_spec: &'a str) -> Self {
+        ChainConfig::chain_spec(chain_spec)
+    }
+}
+
+impl<'a> From<String> for ChainConfig<'a> {
+    fn from(chain_spec: String) -> Self {
+        ChainConfig::chain_spec(chain_spec)
+    }
+}
+
+impl<'a> ChainConfig<'a> {
+    /// Construct a chain config from a chain spec.
+    pub fn chain_spec(chain_spec: impl Into<Cow<'a, str>>) -> Self {
+        ChainConfig {
+            chain_spec: chain_spec.into(),
+        }
+    }
+
+    /// Set the bootnodes to the given ones.
+    pub fn set_bootnodes<S: AsRef<str>>(
+        self,
+        bootnodes: impl IntoIterator<Item = S>,
+    ) -> Result<Self, ChainConfigError> {
+        let mut chain_spec_json: Value = serde_json::from_str(&self.chain_spec)
+            .map_err(|_e| ChainConfigError::InvalidSpecFormat)?;
+
+        if let Value::Object(map) = &mut chain_spec_json {
+            let bootnodes = bootnodes
+                .into_iter()
+                .map(|s| Value::String(s.as_ref().to_owned()))
+                .collect();
+
+            map.insert("bootNodes".to_string(), Value::Array(bootnodes));
+        } else {
+            return Err(ChainConfigError::InvalidSpecFormat);
+        }
+
+        Ok(ChainConfig {
+            chain_spec: Cow::Owned(chain_spec_json.to_string()),
+        })
+    }
+
+    // Used internally to fetch the chain spec back out.
+    pub(crate) fn as_chain_spec(&self) -> &str {
+        &self.chain_spec
+    }
+}