make plc resolver location configurable

src/lib.rs

@@ -1,4 +1,4 @@
-use std::collections::BTreeSet;
+use std::{borrow::Cow, collections::BTreeSet};
 
 use anyhow::Result;
 use bytes::Bytes;
@@ -11,6 +11,7 @@ pub struct RelayServer {
     pub db_users: sled::Tree,
     pub db_index_cursors: sled::Tree,
 
+    pub plc_resolver: Cow<'static, str>,
     pub known_good_hosts: Mutex<BTreeSet<String>>,
     pub active_indexers: Mutex<BTreeSet<String>>,
 
@@ -32,6 +33,7 @@ impl RelayServer {
             event_tx,
             raw_block_tx,
 
+            plc_resolver: Cow::Borrowed("plc.directory"),
             known_good_hosts: Mutex::new(hosts.into_iter().collect()),
             active_indexers: Default::default(),
 

src/main.rs

@@ -1,6 +1,6 @@
 use anyhow::Result;
 use clap::Parser;
-use std::{net::SocketAddr, str::FromStr, sync::Arc};
+use std::{borrow::Cow, net::SocketAddr, str::FromStr, sync::Arc};
 use tokio::sync::mpsc;
 use tracing_subscriber::{fmt, prelude::*, EnvFilter};
 
@@ -21,6 +21,10 @@ struct Args {
     /// Database RAM cache capacity in megabytes
     #[arg(long, default_value_t = 1024)]
     cache_capacity: u64,
+
+    /// did:plc directory HTTPS host. defaults to plc.directory if unset
+    #[arg(long)]
+    plc_resolver: Option<String>,
 }
 
 #[tokio::main]
@@ -41,7 +45,12 @@ async fn main() -> Result<()> {
 
     let (event_tx, event_rx) = mpsc::channel(128);
 
-    let server = Arc::new(RelayServer::new(db, event_tx));
+    let mut server = RelayServer::new(db, event_tx);
+    if let Some(plc_directory) = args.plc_resolver {
+        server.plc_resolver = Cow::Owned(plc_directory);
+    }
+
+    let server = Arc::new(server);
     let initial_hosts: Vec<String> = {
         let hosts = server.known_good_hosts.lock().await;
         hosts.iter().cloned().collect()

src/user.rs

@@ -47,8 +47,7 @@ fn create_user_from_did_doc(did_doc: DidDocument) -> Result<User> {
 pub async fn fetch_user(server: &RelayServer, did: &str) -> Result<User> {
     tracing::debug!(%did, "fetching user");
     if did.starts_with("did:plc:") {
-        // TODO: configurable plc resolver location
-        let domain = "plc.directory";
+        let domain: &str = &server.plc_resolver;
 
         let tcp_stream = TcpStream::connect((domain, 443)).await?;
         let domain_tls: ServerName<'_> = ServerName::try_from(domain.to_string())?;