fix: return proper docker socket for remote Docker hosts (#1281)

* fix: return proper docker socket for remote Docker hosts

* chore: simplify resetting the config in tests

* docs: document that tc.host will return default docker socket path

docs/features/configuration.md

@@ -80,7 +80,8 @@ _Testcontainers for Go_ will attempt to detect the Docker socket path and config
 
 However, sometimes customization is required. _Testcontainers for Go_ will respect the following order:
 
-1. Read the **tc.host** property in the `~/.testcontainers.properties` file. E.g. `tc.host=tcp://my.docker.host:1234`
+1. Read the **tc.host** property in the `~/.testcontainers.properties` file. E.g. `tc.host=tcp://my.docker.host:1234`. If this property is set, the returned Docker socket path
+will be the default Docker socket path: `/var/run/docker.sock`.
 
 2. Read the **TESTCONTAINERS_DOCKER_SOCKET_OVERRIDE** environment variable.
 Path to Docker's socket. Used by Ryuk, Docker Compose, and a few other containers that need to perform Docker actions.  

internal/testcontainersdocker/docker_host.go

@@ -135,6 +135,11 @@ func extractDockerSocket(ctx context.Context) string {
 func extractDockerSocketFromClient(ctx context.Context, cli client.APIClient) string {
 	tcHost, err := testcontainersHostFromProperties(ctx)
 	if err == nil {
+		// this use case will cover the case when the docker host is a tcp socket
+		if strings.HasPrefix(tcHost, "tcp://") {
+			return "/var/run/docker.sock"
+		}
+
 		return tcHost
 	}
 

internal/testcontainersdocker/docker_host_test.go

@@ -58,7 +58,6 @@ func TestExtractDockerHost(t *testing.T) {
 		tmpHost := "tcp://127.0.0.1:12345"
 		content := "tc.host=" + tmpHost
 
-		config.Reset()
 		setupTestcontainersProperties(t, content)
 
 		host := extractDockerHost(context.Background())
@@ -127,9 +126,7 @@ func TestExtractDockerHost(t *testing.T) {
 			tmpSocket := "tcp://127.0.0.1:12345"
 			content := "tc.host=" + tmpSocket
 
-			config.Reset()
 			setupTestcontainersProperties(t, content)
-			defer config.Reset()
 
 			socket, err := testcontainersHostFromProperties(context.Background())
 			require.Nil(t, err)
@@ -139,9 +136,7 @@ func TestExtractDockerHost(t *testing.T) {
 		t.Run("Testcontainers host is not defined in properties", func(t *testing.T) {
 			content := "ryuk.disabled=false"
 
-			config.Reset()
 			setupTestcontainersProperties(t, content)
-			defer config.Reset()
 
 			socket, err := testcontainersHostFromProperties(context.Background())
 			require.ErrorIs(t, err, ErrTestcontainersHostNotSetInProperties)
@@ -228,7 +223,6 @@ func TestExtractDockerHost(t *testing.T) {
 			tmpSocket := "/this/is/a/sample.sock"
 			content := "docker.host=unix://" + tmpSocket
 
-			config.Reset()
 			setupTestcontainersProperties(t, content)
 
 			socket, err := dockerHostFromProperties(context.Background())
@@ -239,7 +233,6 @@ func TestExtractDockerHost(t *testing.T) {
 		t.Run("Docker host is not defined in properties", func(t *testing.T) {
 			content := "ryuk.disabled=false"
 
-			config.Reset()
 			setupTestcontainersProperties(t, content)
 
 			socket, err := dockerHostFromProperties(context.Background())
@@ -279,30 +272,28 @@ func TestExtractDockerSocketFromClient(t *testing.T) {
 		tmpSocket := "tcp://127.0.0.1:12345"
 		content := "tc.host=" + tmpSocket
 
-		config.Reset()
 		setupTestcontainersProperties(t, content)
-		defer config.Reset()
 
 		socket := extractDockerSocketFromClient(context.Background(), mockCli{OS: "foo"})
-		assert.Equal(t, tmpSocket, socket)
+		assert.Equal(t, "/var/run/docker.sock", socket)
 	})
 
 	t.Run("Docker socket from Testcontainers host takes precedence over TESTCONTAINERS_DOCKER_SOCKET_OVERRIDE", func(t *testing.T) {
 		tmpSocket := "tcp://127.0.0.1:12345"
 		content := "tc.host=" + tmpSocket
 
-		config.Reset()
 		setupTestcontainersProperties(t, content)
-		t.Cleanup(config.Reset)
 
 		t.Cleanup(resetSocketOverrideFn)
 		t.Setenv("TESTCONTAINERS_DOCKER_SOCKET_OVERRIDE", "/path/to/docker.sock")
 
 		socket := extractDockerSocketFromClient(context.Background(), mockCli{OS: "foo"})
-		assert.Equal(t, tmpSocket, socket)
+		assert.Equal(t, "/var/run/docker.sock", socket)
 	})
 
 	t.Run("Docker Socket as Testcontainers environment variable", func(t *testing.T) {
+		setupTestcontainersProperties(t, "")
+
 		t.Cleanup(resetSocketOverrideFn)
 
 		t.Setenv("TESTCONTAINERS_DOCKER_SOCKET_OVERRIDE", "/path/to/docker.sock")
@@ -312,6 +303,8 @@ func TestExtractDockerSocketFromClient(t *testing.T) {
 	})
 
 	t.Run("Unix Docker Socket is passed as DOCKER_HOST variable (Docker Desktop)", func(t *testing.T) {
+		setupTestcontainersProperties(t, "")
+
 		t.Cleanup(resetSocketOverrideFn)
 
 		ctx := context.Background()
@@ -324,6 +317,8 @@ func TestExtractDockerSocketFromClient(t *testing.T) {
 	})
 
 	t.Run("Unix Docker Socket is passed as DOCKER_HOST variable (Not Docker Desktop)", func(t *testing.T) {
+		setupTestcontainersProperties(t, "")
+
 		t.Cleanup(resetSocketOverrideFn)
 
 		ctx := context.Background()
@@ -421,6 +416,8 @@ func setupTestcontainersProperties(t *testing.T, content string) {
 		config.Reset()
 	})
 
+	config.Reset()
+
 	tmpDir := t.TempDir()
 	homeDir := filepath.Join(tmpDir, "home")
 	err := createTmpDir(homeDir)