Allow specify base OCI runtime spec

Signed-off-by: Maksym Pavlenko <pavlenko.maksym@gmail.com>

pkg/server/container_create_test.go

@@ -21,6 +21,7 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/containerd/containerd/oci"
 	imagespec "github.com/opencontainers/image-spec/specs-go/v1"
 	runtimespec "github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/stretchr/testify/assert"
@@ -381,3 +382,23 @@ func TestContainerAnnotationPassthroughContainerSpec(t *testing.T) {
 		})
 	}
 }
+
+func TestBaseRuntimeSpec(t *testing.T) {
+	c := newTestCRIService()
+	c.baseOCISpecs = map[string]*oci.Spec{
+		"/etc/containerd/cri-base.json": {
+			Version:  "1.0.2",
+			Hostname: "old",
+		},
+	}
+
+	out, err := c.runtimeSpec("id1", "/etc/containerd/cri-base.json", oci.WithHostname("new"))
+	assert.NoError(t, err)
+
+	assert.Equal(t, "1.0.2", out.Version)
+	assert.Equal(t, "new", out.Hostname)
+
+	// Make sure original base spec not changed
+	assert.NotEqual(t, out, c.baseOCISpecs["/etc/containerd/cri-base.json"])
+	assert.Equal(t, c.baseOCISpecs["/etc/containerd/cri-base.json"].Hostname, "old")
+}