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Paul Hauner 2019-08-21 14:48:49 +10:00
parent a6da933886
commit a8daf46d5f
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2 changed files with 23 additions and 0 deletions

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@ -20,17 +20,31 @@ impl From<HttpError> for Error {
}
}
/// Used to load "bootstrap" information from the HTTP API of another Lighthouse beacon node.
///
/// Bootstrapping information includes things like genesis and finalized states and blocks, and
/// libp2p connection details.
pub struct Bootstrapper {
url: Url,
}
impl Bootstrapper {
/// Parses the given `server` as a URL, instantiating `Self`.
pub fn from_server_string(server: String) -> Result<Self, String> {
Ok(Self {
url: Url::parse(&server).map_err(|e| format!("Invalid bootstrap server url: {}", e))?,
})
}
/// Build a multiaddr using the HTTP server URL that is not guaranteed to be correct.
///
/// The address is created by querying the HTTP server for it's listening libp2p addresses.
/// Then, we find the first TCP port in those addresses and combine the port with the URL of
/// the server.
///
/// For example, the server `http://192.168.0.1` might end up with a `best_effort_multiaddr` of
/// `/ipv4/192.168.0.1/tcp/9000` if the server advertises a listening address of
/// `/ipv4/172.0.0.1/tcp/9000`.
pub fn best_effort_multiaddr(&self) -> Option<Multiaddr> {
let tcp_port = self.first_listening_tcp_port()?;
@ -47,6 +61,8 @@ impl Bootstrapper {
Some(multiaddr)
}
/// Reads the server's listening libp2p addresses and returns the first TCP port protocol it
/// finds, if any.
fn first_listening_tcp_port(&self) -> Option<u16> {
self.listen_addresses().ok()?.iter().find_map(|multiaddr| {
multiaddr.iter().find_map(|protocol| match protocol {
@ -56,6 +72,7 @@ impl Bootstrapper {
})
}
/// Returns the IPv4 address of the server URL, unless it contains a FQDN.
pub fn server_ipv4_addr(&self) -> Option<Ipv4Addr> {
match self.url.host()? {
Host::Ipv4(addr) => Some(addr),
@ -63,15 +80,18 @@ impl Bootstrapper {
}
}
/// Returns the servers ENR address.
pub fn enr(&self) -> Result<Enr, String> {
get_enr(self.url.clone()).map_err(|e| format!("Unable to get ENR: {:?}", e))
}
/// Returns the servers listening libp2p addresses.
pub fn listen_addresses(&self) -> Result<Vec<Multiaddr>, String> {
get_listen_addresses(self.url.clone())
.map_err(|e| format!("Unable to get listen addresses: {:?}", e))
}
/// Returns the genesis block and state.
pub fn genesis<T: EthSpec>(&self) -> Result<(BeaconState<T>, BeaconBlock<T>), String> {
let genesis_slot = Slot::new(0);
@ -83,6 +103,7 @@ impl Bootstrapper {
Ok((state, block))
}
/// Returns the most recent finalized state and block.
pub fn finalized<T: EthSpec>(&self) -> Result<(BeaconState<T>, BeaconBlock<T>), String> {
let slots_per_epoch = get_slots_per_epoch(self.url.clone())
.map_err(|e| format!("Unable to get slots per epoch: {:?}", e))?;

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@ -158,6 +158,8 @@ impl Config {
}
}
/// Perform the HTTP bootstrapping procedure, reading an ENR and multiaddr from the HTTP server and
/// adding them to the `config`.
fn do_bootstrapping(config: &mut Config, server: String, log: &slog::Logger) -> Result<(), String> {
// Set the genesis state source.
config.genesis_state = GenesisState::HttpBootstrap {