From 0aab4b1ac2ba9c08b351aa0c0340b887eee7f060 Mon Sep 17 00:00:00 2001
From: Matthew Penner <me@matthewp.io>
Date: Fri, 8 Jan 2021 08:19:33 -0700
Subject: [PATCH] environment(docker): re-attach to container logs after EOF

---
 environment/docker/container.go | 41 ++++++++++++++++++++++-----------
 1 file changed, 28 insertions(+), 13 deletions(-)

diff --git a/environment/docker/container.go b/environment/docker/container.go
index 9effb29..1661e1e 100644
--- a/environment/docker/container.go
+++ b/environment/docker/container.go
@@ -310,23 +310,38 @@ func (e *Environment) followOutput() error {
 		return err
 	}
 
-	go func(reader io.ReadCloser) {
-		defer reader.Close()
-
-		events := e.Events()
-
-		err := system.ScanReader(reader, func(line string) {
-			events.Publish(environment.ConsoleOutputEvent, line)
-		})
-
-		if err != nil && err != io.EOF {
-			log.WithField("error", err).WithField("container_id", e.Id).Warn("error processing scanner line in console output")
-		}
-	}(reader)
+	go e.scanOutput(reader)
 
 	return nil
 }
 
+func (e *Environment) scanOutput(reader io.ReadCloser) {
+	defer reader.Close()
+
+	events := e.Events()
+
+	err := system.ScanReader(reader, func(line string) {
+		events.Publish(environment.ConsoleOutputEvent, line)
+	})
+
+	if err != nil && err != io.EOF {
+		log.WithField("error", err).WithField("container_id", e.Id).Warn("error processing scanner line in console output")
+		return
+	}
+
+	// Return here if the server is offline or currently stopping.
+	if e.State() == environment.ProcessStoppingState || e.State() == environment.ProcessOfflineState {
+		return
+	}
+
+	// Close the current reader before starting a new one, the defer will still run
+	// but it will do nothing if we already closed the stream.
+	_ = reader.Close()
+
+	// Start following the output of the server again.
+	go e.followOutput()
+}
+
 // Pulls the image from Docker. If there is an error while pulling the image from the source
 // but the image already exists locally, we will report that error to the logger but continue
 // with the process.