From 7c83a5206fbe4d844e10a1a49be7a15054d9ef54 Mon Sep 17 00:00:00 2001
From: Chi-Sheng Liu <chishengliu@chishengliu.com>
Date: Wed, 14 Feb 2024 05:19:40 +0800
Subject: [PATCH] fix: Use ExtraHosts only for linux machines with native
 docker engine

Signed-off-by: Chi-Sheng Liu <chishengliu@chishengliu.com>
---
 pkg/docker/docker_util.go      | 16 +++++++++++++++-
 pkg/docker/docker_util_test.go |  8 ++++----
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/pkg/docker/docker_util.go b/pkg/docker/docker_util.go
index e9315cab..f15c2a8b 100644
--- a/pkg/docker/docker_util.go
+++ b/pkg/docker/docker_util.go
@@ -6,7 +6,9 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/fs"
 	"os"
+	"runtime"
 	"strings"
 
 	"github.com/docker/docker/client"
@@ -60,6 +62,18 @@ var (
 	ExtraHosts         = []string{"host.docker.internal:host-gateway"}
 )
 
+// GetExtraHosts will return extra hosts for the container
+func GetExtraHosts() []string {
+	// Linux machine with native docker engine does not have host.docker.internal and needs to add the hostname mapping manually.
+	if runtime.GOOS == "linux" {
+		// Here assume that if /var/run/docker.sock exists and is a socket file and is not symbolic link, then the docker engine is native
+		if fileInfo, err := os.Lstat("/var/run/docker.sock"); err == nil && fileInfo.Mode().Type() == fs.ModeSocket {
+			return ExtraHosts
+		}
+	}
+	return []string{}
+}
+
 // GetDockerClient will returns the docker client
 func GetDockerClient() (Docker, error) {
 	if Client == nil {
@@ -266,7 +280,7 @@ func StartContainer(ctx context.Context, cli Docker, volumes []mount.Mount, expo
 		Mounts:       volumes,
 		PortBindings: portBindings,
 		Privileged:   true,
-		ExtraHosts:   ExtraHosts, // add it because linux machine doesn't have this host name by default
+		ExtraHosts:   GetExtraHosts(),
 	}, nil,
 		nil, name)
 
diff --git a/pkg/docker/docker_util_test.go b/pkg/docker/docker_util_test.go
index 0de840bb..48937c6c 100644
--- a/pkg/docker/docker_util_test.go
+++ b/pkg/docker/docker_util_test.go
@@ -196,7 +196,7 @@ func TestStartContainer(t *testing.T) {
 			Mounts:       Volumes,
 			PortBindings: p2,
 			Privileged:   true,
-			ExtraHosts:   ExtraHosts,
+			ExtraHosts:   GetExtraHosts(),
 		}, nil, nil, mock.Anything).Return(container.ContainerCreateCreatedBody{
 			ID: "Hello",
 		}, nil)
@@ -226,7 +226,7 @@ func TestStartContainer(t *testing.T) {
 			Mounts:       Volumes,
 			PortBindings: p2,
 			Privileged:   true,
-			ExtraHosts:   ExtraHosts,
+			ExtraHosts:   GetExtraHosts(),
 		}, nil, nil, mock.Anything).Return(container.ContainerCreateCreatedBody{
 			ID: "Hello",
 		}, nil)
@@ -253,7 +253,7 @@ func TestStartContainer(t *testing.T) {
 			Mounts:       Volumes,
 			PortBindings: p2,
 			Privileged:   true,
-			ExtraHosts:   ExtraHosts,
+			ExtraHosts:   GetExtraHosts(),
 		}, nil, nil, mock.Anything).Return(container.ContainerCreateCreatedBody{
 			ID: "",
 		}, fmt.Errorf("error"))
@@ -279,7 +279,7 @@ func TestStartContainer(t *testing.T) {
 			Mounts:       Volumes,
 			PortBindings: p2,
 			Privileged:   true,
-			ExtraHosts:   ExtraHosts,
+			ExtraHosts:   GetExtraHosts(),
 		}, nil, nil, mock.Anything).Return(container.ContainerCreateCreatedBody{
 			ID: "Hello",
 		}, nil)