Expose GitHub hash in UI (#604)

* Expose GitHub hash in UI

* Prettier:fix

* cargo fmt

* Update tests

* Fix test

backend/telemetry_core/src/aggregator/inner_loop.rs

@@ -451,7 +451,10 @@ impl InnerLoop {
 
                 // Tell the new feed subscription some basic things to get it going:
                 let mut feed_serializer = FeedMessageSerializer::new();
-                feed_serializer.push(feed_message::Version(32));
+                feed_serializer.push(feed_message::Version(crate::feed_message::FEED_VERSION));
+                feed_serializer.push(feed_message::TelemetryInfo {
+                    git_hash: crate::GIT_HASH,
+                });
                 for chain in self.node_state.iter_chains() {
                     feed_serializer.push(feed_message::AddedChain(
                         chain.label(),

backend/telemetry_core/src/feed_message.rs

@@ -25,6 +25,10 @@ use common::node_types::{
 };
 use serde_json::to_writer;
 
+/// The version of the feed messages. This should be incremented
+/// on the backend and frontend when the feed API changes.
+pub const FEED_VERSION: usize = 33;
+
 type FeedNodeId = usize;
 
 pub trait FeedMessage {
@@ -123,6 +127,7 @@ actions! {
     20: StaleNode,
     21: NodeIOUpdate<'_>,
     22: ChainStatsUpdate<'_>,
+    23: TelemetryInfo,
 }
 
 #[derive(Serialize)]
@@ -252,3 +257,8 @@ pub struct ChainStats {
     pub disk_random_write_score: Ranking<(u32, Option<u32>)>,
     pub cpu_vendor: Ranking<String>,
 }
+
+#[derive(Serialize)]
+pub struct TelemetryInfo {
+    pub git_hash: &'static str,
+}

backend/telemetry_core/src/main.rs

@@ -41,6 +41,7 @@ use jemallocator::Jemalloc;
 #[global_allocator]
 static GLOBAL: Jemalloc = Jemalloc;
 
+const GIT_HASH: &str = env!("GIT_HASH");
 const VERSION: &str = env!("CARGO_PKG_VERSION");
 const AUTHORS: &str = env!("CARGO_PKG_AUTHORS");
 const NAME: &str = "Substrate Telemetry Backend Core";