Stat path to binary to handle raw exec driver interpolated binary path

client/driver/executor/executor.go

@@ -504,6 +504,12 @@ func (e *UniversalExecutor) Stats() (*cstructs.TaskResourceUsage, error) {
 // the following locations, in-order: task/local/, task/, based on host $PATH.
 // The return path is absolute.
 func lookupBin(taskDir string, bin string) (string, error) {
+	// Check the binary path first
+	// This handles the case where the job spec sends a fully interpolated path to the binary
+	if _, err := os.Stat(bin); err == nil {
+		return bin, nil
+	}
+
 	// Check in the local directory
 	local := filepath.Join(taskDir, allocdir.TaskLocal, bin)
 	if _, err := os.Stat(local); err == nil {

client/driver/executor/executor_test.go

@@ -247,3 +247,42 @@ func TestUniversalExecutor_MakeExecutable(t *testing.T) {
 		t.Fatalf("expected permissions %v; got %v", exp, act)
 	}
 }
+
+func TestUniversalExecutor_LookupPath(t *testing.T) {
+	t.Parallel()
+	// Create a temp dir
+	tmpDir, err := ioutil.TempDir("", "")
+	require := require.New(t)
+	require.Nil(err)
+	defer os.Remove(tmpDir)
+
+	// Make a foo subdir
+	os.MkdirAll(filepath.Join(tmpDir, "foo"), 0700)
+
+	// Write a file under foo
+	filePath := filepath.Join(tmpDir, "foo", "tmp.txt")
+	err = ioutil.WriteFile(filePath, []byte{1, 2}, os.ModeAppend)
+	require.Nil(err)
+
+	// Lookup with full path to binary
+	_, err = lookupBin("dummy", filePath)
+	require.Nil(err)
+
+	// Write a file under local subdir
+	os.MkdirAll(filepath.Join(tmpDir, "local"), 0700)
+	filePath2 := filepath.Join(tmpDir, "local", "tmp.txt")
+	ioutil.WriteFile(filePath2, []byte{1, 2}, os.ModeAppend)
+
+	// Lookup with file name, should find the one we wrote above
+	_, err = lookupBin(tmpDir, "tmp.txt")
+	require.Nil(err)
+
+	// Write a file under task dir
+	filePath3 := filepath.Join(tmpDir, "tmp.txt")
+	ioutil.WriteFile(filePath3, []byte{1, 2}, os.ModeAppend)
+
+	// Lookup with file name, should find the one we wrote above
+	_, err = lookupBin(tmpDir, "tmp.txt")
+	require.Nil(err)
+
+}