implement MultiReporter

Cargo.toml

@@ -13,6 +13,7 @@ aws-arn = { version = "0.3", optional = true }
 aws-config = { version = "1", optional = true }
 aws-sdk-s3 = { version = "1", optional = true }
 chrono = "0.4"
+futures = { version = "0.3", default-features = false }
 libloading = "0.8"
 reqwest = { version = "0.12", default-features = false, optional = true, features = ["charset", "http2", "rustls-tls"] }
 serde_json = "1"

src/metadata/mod.rs

@@ -30,3 +30,12 @@ pub struct ReportMetadata<'a> {
 
 #[cfg(feature = "aws-metadata")]
 pub mod aws;
+
+/// [private] dummy metadata to make testing easier
+#[cfg(test)]
+pub(crate) const DUMMY_METADATA: ReportMetadata<'static> = ReportMetadata {
+    instance: &AgentMetadata::Other,
+    start: Duration::from_secs(1),
+    end: Duration::from_secs(2),
+    reporting_interval: Duration::from_secs(1),
+};

src/reporter/mod.rs

@@ -7,6 +7,7 @@ use async_trait::async_trait;
 
 use crate::metadata::ReportMetadata;
 
+pub mod multi;
 #[cfg(feature = "s3")]
 pub mod s3;
 

src/reporter/multi.rs

@@ -0,0 +1,170 @@
+use async_trait::async_trait;
+
+use crate::metadata::ReportMetadata;
+
+use super::Reporter;
+
+use std::fmt;
+
+/// An aggregated error that contains an error per reporter. A reporter is identified
+/// by the result of its Debug impl.
+#[derive(Debug, thiserror::Error)]
+struct MultiError {
+    errors: Vec<(String, Box<dyn std::error::Error + Send>)>,
+}
+
+impl fmt::Display for MultiError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{{")?;
+        let mut first = true;
+        for (reporter, err) in self.errors.iter() {
+            if !first {
+                write!(f, ", ")?;
+            }
+            first = false;
+            write!(f, "{}: {}", reporter, err)?;
+        }
+        write!(f, "}}")
+    }
+}
+
+#[derive(Debug)]
+/// A reporter that reports profiling results to several destinations.
+///
+/// If one of the destinations errors, it will continue reporting to the other ones.
+pub struct MultiReporter {
+    reporters: Vec<Box<dyn Reporter + Send + Sync>>,
+}
+
+impl MultiReporter {
+    /// Create a new MultiReporter from a set of reporters
+    pub fn new(reporters: Vec<Box<dyn Reporter + Send + Sync>>) -> Self {
+        MultiReporter { reporters }
+    }
+}
+
+#[async_trait]
+impl Reporter for MultiReporter {
+    async fn report(
+        &self,
+        jfr: Vec<u8>,
+        metadata: &ReportMetadata,
+    ) -> Result<(), Box<dyn std::error::Error + Send>> {
+        let jfr_ref = &jfr[..];
+        let errors = futures::future::join_all(self.reporters.iter().map(|reporter| async move {
+            reporter
+                .report(jfr_ref.to_owned(), metadata)
+                .await
+                .map_err(move |e| (format!("{:?}", reporter), e))
+        }))
+        .await;
+        // return all errors
+        let errors: Vec<_> = errors.into_iter().flat_map(|e| e.err()).collect();
+        if errors.is_empty() {
+            Ok(())
+        } else {
+            Err(Box::new(MultiError { errors }))
+        }
+    }
+}
+
+#[cfg(test)]
+pub mod test {
+    use std::{
+        sync::{
+            atomic::{self, AtomicBool},
+            Arc,
+        },
+        time::Duration,
+    };
+
+    use async_trait::async_trait;
+
+    use crate::{
+        metadata::{ReportMetadata, DUMMY_METADATA},
+        reporter::Reporter,
+    };
+
+    use super::MultiReporter;
+
+    #[derive(Debug)]
+    struct OkReporter(Arc<AtomicBool>);
+    #[async_trait]
+    impl Reporter for OkReporter {
+        async fn report(
+            &self,
+            _jfr: Vec<u8>,
+            _metadata: &ReportMetadata,
+        ) -> Result<(), Box<dyn std::error::Error + Send>> {
+            tokio::time::sleep(tokio::time::Duration::from_secs(1)).await;
+            self.0.store(true, atomic::Ordering::Relaxed);
+            Ok(())
+        }
+    }
+
+    #[derive(Debug, thiserror::Error)]
+    enum Error {
+        #[error("failed: {0}")]
+        Failed(String),
+    }
+
+    #[derive(Debug)]
+    struct ErrReporter(String);
+    #[async_trait]
+    impl Reporter for ErrReporter {
+        async fn report(
+            &self,
+            _jfr: Vec<u8>,
+            _metadata: &ReportMetadata,
+        ) -> Result<(), Box<dyn std::error::Error + Send>> {
+            Err(Box::new(Error::Failed(self.0.clone())))
+        }
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn test_multi_reporter_ok() {
+        let signals: Vec<_> = (0..10).map(|_| Arc::new(AtomicBool::new(false))).collect();
+        let reporter = MultiReporter::new(
+            signals
+                .iter()
+                .map(|signal| {
+                    Box::new(OkReporter(signal.clone())) as Box<dyn Reporter + Send + Sync>
+                })
+                .collect(),
+        );
+        // test that reports are done in parallel
+        tokio::time::timeout(
+            Duration::from_secs(2),
+            reporter.report(vec![], &DUMMY_METADATA),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+        // test that reports are done
+        assert!(signals.iter().all(|s| s.load(atomic::Ordering::Relaxed)));
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn test_multi_reporter_err() {
+        let signal_before = Arc::new(AtomicBool::new(false));
+        let signal_after = Arc::new(AtomicBool::new(false));
+        let reporter = MultiReporter::new(vec![
+            Box::new(OkReporter(signal_before.clone())) as Box<dyn Reporter + Send + Sync>,
+            Box::new(ErrReporter("foo".to_owned())) as Box<dyn Reporter + Send + Sync>,
+            Box::new(ErrReporter("bar".to_owned())) as Box<dyn Reporter + Send + Sync>,
+            Box::new(OkReporter(signal_after.clone())) as Box<dyn Reporter + Send + Sync>,
+        ]);
+        // test that reports are done and return an error
+        let err = format!(
+            "{}",
+            reporter.report(vec![], &DUMMY_METADATA).await.unwrap_err()
+        );
+        assert_eq!(
+            err,
+            "{ErrReporter(\"foo\"): failed: foo, ErrReporter(\"bar\"): failed: bar}"
+        );
+        // test that reports are done even though a reporter errored
+        assert!(signal_before.load(atomic::Ordering::Relaxed));
+        assert!(signal_after.load(atomic::Ordering::Relaxed));
+    }
+}