Kill running acceptance test nodes on error (#1770)

And show the output from those nodes.

These changes help us diagnose errors that happen while one or more
acceptance test nodes are running.

zebra-test/src/command.rs

@@ -320,6 +320,34 @@ impl<T> TestChild<T> {
         Err(report)
     }
 
+    /// Kill `child`, wait for its output, and use that output as the context for
+    /// an error report based on `error`.
+    #[instrument(skip(self, result))]
+    pub fn kill_on_error<V, E>(mut self, result: Result<V, E>) -> Result<(V, Self), Report>
+    where
+        E: Into<Report> + Send + Sync + 'static,
+    {
+        let mut error: Report = match result {
+            Ok(success) => return Ok((success, self)),
+            Err(error) => error.into(),
+        };
+
+        if self.is_running() {
+            let kill_res = self.kill();
+            if let Err(kill_err) = kill_res {
+                error = error.wrap_err(kill_err);
+            }
+        }
+
+        let output_res = self.wait_with_output();
+        let error = match output_res {
+            Err(output_err) => error.wrap_err(output_err),
+            Ok(output) => error.context_from(&output),
+        };
+
+        Err(error)
+    }
+
     fn past_deadline(&self) -> bool {
         self.deadline
             .map(|deadline| Instant::now() > deadline)

zebrad/tests/acceptance.rs

@@ -951,7 +951,7 @@ async fn metrics_endpoint() -> Result<()> {
     config.metrics.endpoint_addr = Some(endpoint.parse().unwrap());
 
     let dir = TempDir::new("zebrad_tests")?.with_config(&mut config)?;
-    let mut child = dir.spawn_child(&["start"])?;
+    let child = dir.spawn_child(&["start"])?;
 
     // Run `zebrad` for a few seconds before testing the endpoint
     // Since we're an async function, we have to use a sleep future, not thread sleep.
@@ -961,9 +961,11 @@ async fn metrics_endpoint() -> Result<()> {
     let client = Client::new();
 
     // Test metrics endpoint
-    let res = client.get(url.try_into().expect("url is valid")).await?;
+    let res = client.get(url.try_into().expect("url is valid")).await;
+    let (res, child) = child.kill_on_error(res)?;
     assert!(res.status().is_success());
-    let body = hyper::body::to_bytes(res).await?;
+    let body = hyper::body::to_bytes(res).await;
+    let (body, mut child) = child.kill_on_error(body)?;
     assert!(
         std::str::from_utf8(&body)
             .expect("metrics response is valid UTF-8")
@@ -1004,7 +1006,7 @@ async fn tracing_endpoint() -> Result<()> {
     config.tracing.endpoint_addr = Some(endpoint.parse().unwrap());
 
     let dir = TempDir::new("zebrad_tests")?.with_config(&mut config)?;
-    let mut child = dir.spawn_child(&["start"])?;
+    let child = dir.spawn_child(&["start"])?;
 
     // Run `zebrad` for a few seconds before testing the endpoint
     // Since we're an async function, we have to use a sleep future, not thread sleep.
@@ -1016,9 +1018,11 @@ async fn tracing_endpoint() -> Result<()> {
     // Test tracing endpoint
     let res = client
         .get(url_default.try_into().expect("url_default is valid"))
-        .await?;
+        .await;
+    let (res, child) = child.kill_on_error(res)?;
     assert!(res.status().is_success());
-    let body = hyper::body::to_bytes(res).await?;
+    let body = hyper::body::to_bytes(res).await;
+    let (body, child) = child.kill_on_error(body)?;
     assert!(std::str::from_utf8(&body).unwrap().contains(
         "This HTTP endpoint allows dynamic control of the filter applied to\ntracing events."
     ));
@@ -1027,13 +1031,16 @@ async fn tracing_endpoint() -> Result<()> {
     let request = Request::post(url_filter.clone())
         .body(Body::from("zebrad=debug"))
         .unwrap();
-    let _post = client.request(request).await?;
+    let post = client.request(request).await;
+    let (_post, child) = child.kill_on_error(post)?;
 
     let tracing_res = client
         .get(url_filter.try_into().expect("url_filter is valid"))
-        .await?;
+        .await;
+    let (tracing_res, child) = child.kill_on_error(tracing_res)?;
     assert!(tracing_res.status().is_success());
-    let tracing_body = hyper::body::to_bytes(tracing_res).await?;
+    let tracing_body = hyper::body::to_bytes(tracing_res).await;
+    let (tracing_body, mut child) = child.kill_on_error(tracing_body)?;
     assert!(std::str::from_utf8(&tracing_body)
         .unwrap()
         .contains("zebrad=debug"));
@@ -1201,25 +1208,35 @@ where
     }
 
     // Start the first node
-    let mut node1 = first_dir.spawn_child(&["start"])?;
+    let node1 = first_dir.spawn_child(&["start"])?;
 
     // Wait a bit to spawn the second node, we want the first fully started.
     std::thread::sleep(LAUNCH_DELAY);
 
     // Spawn the second node
-    let node2 = second_dir.spawn_child(&["start"])?;
+    let node2 = second_dir.spawn_child(&["start"]);
+    let (node2, mut node1) = node1.kill_on_error(node2)?;
 
     // Wait a few seconds and kill first node.
     // Second node is terminated by panic, no need to kill.
     std::thread::sleep(LAUNCH_DELAY);
-    node1.kill()?;
+    let node1_kill_res = node1.kill();
+    let (_, node2) = node2.kill_on_error(node1_kill_res)?;
 
     // In node1 we want to check for the success regex
-    let output1 = node1.wait_with_output()?;
-    output1.stdout_contains(first_stdout_regex)?;
-    output1
+    // If there are any errors, we also want to print the node2 output.
+    let output1 = node1.wait_with_output();
+    let (output1, node2) = node2.kill_on_error(output1)?;
+    let res1 = output1.stdout_contains(first_stdout_regex);
+    let (_, node2) = node2.kill_on_error(res1)?;
+    let res1 = output1
         .assert_was_killed()
-        .wrap_err("Possible port conflict. Are there other acceptance tests running?")?;
+        .wrap_err("Possible port conflict. Are there other acceptance tests running?");
+    let (_, mut node2) = node2.kill_on_error(res1)?;
+
+    // node2 should have panicked due to a conflict. Kill it here
+    // anyway, so it doesn't outlive the test on error.
+    let _ = node2.kill();
 
     // In the second node we look for the conflict regex
     let output2 = node2.wait_with_output()?;