config: Ability to configure dns server list (#54)

CHANGELOG.md

@@ -1,3 +1,9 @@
+## Unreleased
+
+FEATURES:
+
+* config: Ability to configure dns server list
+
 ## 0.1.0
 
 FEATURES:

README.md

@@ -269,6 +269,16 @@ config {
 }
 ```
 
+* **dns** - (Optional)  A list of dns servers. Replaces the default from podman binary and containers.conf.
+
+```
+config {
+  dns = [
+    "1.1.1.1"
+  ]
+}
+```
+
 ## Example job
 
 ```

config.go

@@ -59,6 +59,7 @@ var (
 		"command":            hclspec.NewAttr("command", "string", false),
 		"cap_add":            hclspec.NewAttr("cap_add", "list(string)", false),
 		"cap_drop":           hclspec.NewAttr("cap_drop", "list(string)", false),
+		"dns":                hclspec.NewAttr("dns", "list(string)", false),
 		"entrypoint":         hclspec.NewAttr("entrypoint", "string", false),
 		"working_dir":        hclspec.NewAttr("working_dir", "string", false),
 		"hostname":           hclspec.NewAttr("hostname", "string", false),
@@ -113,4 +114,5 @@ type TaskConfig struct {
 	Volumes           []string           `codec:"volumes"`
 	CapAdd            []string           `codec:"cap_add"`
 	CapDrop           []string           `codec:"cap_drop"`
+	Dns               []string           `codec:"dns"`
 }

driver.go

@@ -433,6 +433,7 @@ func (d *Driver) StartTask(cfg *drivers.TaskConfig) (*drivers.TaskHandle, *drive
 		CpuShares:         &cpuShares,
 		CapAdd:            &driverConfig.CapAdd,
 		CapDrop:           &driverConfig.CapDrop,
+		Dns:               &driverConfig.Dns,
 		LogOpt:            &logOpts,
 		Hostname:          &driverConfig.Hostname,
 		Init:              &driverConfig.Init,

driver_test.go

@@ -916,6 +916,58 @@ func TestPodmanDriver_Caps(t *testing.T) {
 	require.NotContains(t, inspectData.EffectiveCaps, "CAP_MKNOD")
 }
 
+// check dns server configuration
+func TestPodmanDriver_Dns(t *testing.T) {
+	if !tu.IsCI() {
+		t.Parallel()
+	}
+
+	taskCfg := newTaskConfig("", []string{
+		"cat",
+		"/etc/resolv.conf",
+	})
+	// config {
+	//   dns = [
+	//     "1.1.1.1"
+	//   ]
+	// }
+	taskCfg.Dns = []string{"1.1.1.1"}
+
+	task := &drivers.TaskConfig{
+		ID:        uuid.Generate(),
+		Name:      "dns",
+		AllocID:   uuid.Generate(),
+		Resources: createBasicResources(),
+	}
+	require.NoError(t, task.EncodeConcreteDriverConfig(&taskCfg))
+
+	d := podmanDriverHarness(t, nil)
+	cleanup := d.MkAllocDir(task, true)
+	defer cleanup()
+
+	_, _, err := d.StartTask(task)
+	require.NoError(t, err)
+
+	defer d.DestroyTask(task.ID, true)
+
+	// Attempt to wait
+	waitCh, err := d.WaitTask(context.Background(), task.ID)
+	require.NoError(t, err)
+
+	select {
+	case res := <-waitCh:
+		// should have a exitcode=0 result
+		require.True(t, res.Successful())
+	case <-time.After(time.Duration(tu.TestMultiplier()*2) * time.Second):
+		t.Fatalf("Container did not exit in time")
+	}
+
+	// see if stdout was populated with the correct output
+	tasklog := readLogfile(t, task)
+	require.Contains(t, tasklog, "nameserver 1.1.1.1")
+
+}
+
 // TestPodmanDriver_NetworkMode asserts we can specify different network modes
 // Default podman cni subnet 10.88.0.0/16
 func TestPodmanDriver_NetworkMode(t *testing.T) {