Expose GitHub hash in UI (#604)

* Expose GitHub hash in UI

* Prettier:fix

* cargo fmt

* Update tests

* Fix test

backend/Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "ahash"
@@ -1806,6 +1806,7 @@ dependencies = [
  "futures",
  "http",
  "log",
+ "serde",
  "serde_json",
  "soketto",
  "thiserror",

backend/telemetry_core/build.rs

@@ -0,0 +1,12 @@
+use std::process::Command;
+
+fn main() {
+    // Fetch the git hash if possible, <unknown> if not.
+    let git_hash = Command::new("git")
+        .args(&["rev-parse", "HEAD"])
+        .output()
+        .map(|output| String::from_utf8(output.stdout).unwrap_or_default())
+        .unwrap_or_default();
+
+    println!("cargo:rustc-env=GIT_HASH={}", git_hash);
+}

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";

backend/telemetry_core/tests/e2e_tests.rs

@@ -46,6 +46,8 @@ use test_utils::{
     workspace::{start_server, start_server_debug, CoreOpts, ServerOpts, ShardOpts},
 };
 
+const GIT_HASH: &str = env!("GIT_HASH");
+
 fn polkadot_genesis_hash() -> BlockHash {
     BlockHash::from_str("0x91b171bb158e2d3848fa23a9f1c25182fb8e20313b2c1eb49219da7a70ce90c3")
         .expect("valid polkadot genesis hash")
@@ -69,7 +71,12 @@ async fn e2e_feed_sent_version_on_connect() {
     let feed_messages = feed_rx.recv_feed_messages().await.unwrap();
     assert_eq!(
         feed_messages,
-        vec![FeedMessage::Version(32)],
+        vec![
+            FeedMessage::Version(33),
+            FeedMessage::TelemetryInfo {
+                git_hash: GIT_HASH.to_string()
+            }
+        ],
         "expecting version"
     );
 
@@ -127,7 +134,12 @@ async fn e2e_multiple_feeds_sent_version_on_connect() {
     for feed_messages in responses {
         assert_eq!(
             feed_messages.expect("should have messages"),
-            vec![FeedMessage::Version(32)],
+            vec![
+                FeedMessage::Version(33),
+                FeedMessage::TelemetryInfo {
+                    git_hash: GIT_HASH.to_string()
+                }
+            ],
             "expecting version"
         );
     }

backend/test_utils/Cargo.toml

@@ -11,6 +11,7 @@ anyhow = "1.0.41"
 futures = "0.3.15"
 http = "0.2.4"
 log = "0.4.14"
+serde = "1"
 serde_json = "1.0.64"
 soketto = "0.7.1"
 thiserror = "1.0.25"

backend/test_utils/src/feed_message_de.rs

@@ -122,6 +122,9 @@ pub enum FeedMessage {
         node_id: usize,
         // details: NodeIO, // can't losslessly deserialize
     },
+    TelemetryInfo {
+        git_hash: String,
+    },
     /// A "special" case when we don't know how to decode an action:
     UnknownValue {
         action: u8,
@@ -367,6 +370,18 @@ impl FeedMessage {
                 let (node_id, _node_io): (_, &RawValue) = serde_json::from_str(raw_val.get())?;
                 FeedMessage::NodeIOUpdate { node_id }
             }
+            // Note: 22: ChainStatsUpdate is not here. Add when we want to test it.
+            // TelemetryInfo
+            23 => {
+                #[derive(serde::Deserialize)]
+                struct TelemetryInfo {
+                    git_hash: String,
+                }
+                let val: TelemetryInfo = serde_json::from_str(raw_val.get())?;
+                FeedMessage::TelemetryInfo {
+                    git_hash: val.git_hash,
+                }
+            }
             // A catchall for messages we don't know/care about yet:
             _ => {
                 let value = raw_val.to_string();