add support for multiple streams

config.yaml

@@ -1,5 +1,14 @@
+# Sources
+streams:
+  # The fedi.buzz firehose stream
+  - "https://fedi.buzz/api/v1/streaming/public"
+  # You may list the streaming API of other instances here
+# external https hostname
 hostname: relay.fedi.buzz
+# where your reverse proxy will connect to
 listen_port: 3000
+# ActivityPub signing keypair
 priv_key_file: private-key.pem
 pub_key_file: public-key.pem
+# PostgreSQL
 db: "host=localhost user=relay password=xyz dbname=buzzrelay"

nixos-module.nix

@@ -2,6 +2,12 @@
 { config, lib, pkgs, ... }: {
   options.services.buzzrelay = with lib; {
     enable = mkEnableOption "Enable Fedi.buzz relay";
+    streams = mkOption {
+      type = types.listOf str;
+      default = [
+        "https://fedi.buzz/api/v1/streaming/public"
+      ];
+    };
     listenPort = mkOption {
       type = types.int;
       default = 8000;
@@ -34,6 +40,7 @@
       cfg = config.services.buzzrelay;
       configFile = builtins.toFile "buzzrelay.toml" (
         lib.generators.toYAML {} {
+          streams = cfg.streams;
           hostname = cfg.hostName;
           listen_port = cfg.listenPort;
           priv_key_file = cfg.privKeyFile;

src/config.rs

@@ -1,14 +1,9 @@
 use serde::Deserialize;
 use sigh::{PrivateKey, PublicKey, Key};
 
-fn default_upstream() -> String {
-    "fedi.buzz".to_string()
-}
-
 #[derive(Deserialize)]
 pub struct Config {
-    #[serde(default = "default_upstream")]
-    pub upstream: String,
+    pub streams: Vec<String>,
     pub db: String,
     pub hostname: String,
     pub listen_port: u16,

src/main.rs

@@ -248,6 +248,8 @@ async fn main() {
         &std::env::args().nth(1)
             .expect("Call with config.yaml")
     );
+    let priv_key = config.priv_key();
+    let pub_key = config.pub_key();
 
     let recorder = PrometheusBuilder::new()
         .add_global_label("application", env!("CARGO_PKG_NAME"))
@@ -257,7 +259,7 @@ async fn main() {
 
     let database = db::Database::connect(&config.db).await;
 
-    let stream_rx = stream::spawn(config.upstream.clone());
+    let stream_rx = stream::spawn(config.streams.into_iter());
     let client = Arc::new(
         reqwest::Client::builder()
             .timeout(Duration::from_secs(5))
@@ -272,7 +274,7 @@ async fn main() {
             .unwrap()
     );
     let hostname = Arc::new(config.hostname.clone());
-    relay::spawn(client.clone(), hostname.clone(), database.clone(), config.priv_key(), stream_rx);
+    relay::spawn(client.clone(), hostname.clone(), database.clone(), priv_key.clone(), stream_rx);
 
     let app = Router::new()
         .route("/tag/:tag", get(get_tag_actor).post(post_tag_relay))
@@ -285,8 +287,8 @@ async fn main() {
             database,
             client,
             hostname,
-            priv_key: config.priv_key(),
-            pub_key: config.pub_key(),
+            priv_key,
+            pub_key,
         })
         .merge(SpaRouter::new("/", "static"));
 

src/stream.rs

@@ -13,8 +13,7 @@ pub enum StreamError {
     InvalidContentType,
 }
 
-async fn run(host: &str) -> Result<impl Stream<Item = String>, StreamError> {
-    let url = format!("https://{}/api/v1/streaming/public", host);
+async fn run(url: &str) -> Result<impl Stream<Item = String>, StreamError> {
     let client = reqwest::Client::new();
     let res = client.get(url)
         .timeout(Duration::MAX)
@@ -44,22 +43,25 @@ async fn run(host: &str) -> Result<impl Stream<Item = String>, StreamError> {
     Ok(src)
 }
 
-pub fn spawn<H: Into<String>>(host: H) -> Receiver<String> {
-    let host = host.into();
+pub fn spawn(hosts: impl Iterator<Item = impl Into<String>>) -> Receiver<String> {
     let (tx, rx) = channel(1024);
-    tokio::spawn(async move {
-        loop {
-            match run(&host).await {
-                Ok(stream) =>
-                    stream.for_each(|post| async {
-                        tx.send(post).await.unwrap();
-                    }).await,
-                Err(e) =>
-                    tracing::error!("stream: {:?}", e),
-            }
+    for host in hosts {
+        let host = host.into();
+        let tx = tx.clone();
+        tokio::spawn(async move {
+            loop {
+                match run(&host).await {
+                    Ok(stream) =>
+                        stream.for_each(|post| async {
+                            tx.send(post).await.unwrap();
+                        }).await,
+                    Err(e) =>
+                        tracing::error!("stream: {:?}", e),
+                }
 
-            sleep(Duration::from_secs(1)).await;
-        }
-    });
+                sleep(Duration::from_secs(1)).await;
+            }
+        });
+    }
     rx
 }