template rendering, single values & tests

clab/config/ssh.go

@@ -16,7 +16,7 @@ type Session struct {
 	Session *ssh.Session
 }
 
-func NewSession(username, password string, host string) (*Session, error) {
+func NewSession(username, password, host string) (*Session, error) {
 
 	sshConfig := &ssh.ClientConfig{
 		User: username,

clab/config/template.go

@@ -103,8 +103,7 @@ func RenderLink(link *clab.Link) (*ConfigSnippet, *ConfigSnippet, error) {
 	for k, v := range link.Labels {
 		r := strings.Split(v, ",")
 		switch len(r) {
-		case 1:
-		case 2:
+		case 1, 2:
 			l[k] = r
 		default:
 			log.Warnf("%s: %s contains %d elements: %s", link, k, len(r), v)
@@ -190,24 +189,59 @@ var funcMap = map[string]interface{}{
 		return a[1], nil
 	},
 	"default": func(val interface{}, def interface{}) (interface{}, error) {
-		if val == nil {
-			return def, nil
+		if def == nil {
+			return nil, fmt.Errorf("default value expected")
+		}
+		switch val.(type) {
+		case string:
+			if val == "" {
+				return def, nil
+			}
+		default:
+			if val == nil {
+				return def, nil
+			}
 		}
 		return val, nil
 	},
 	"contains": func(str interface{}, substr interface{}) (interface{}, error) {
 		return strings.Contains(fmt.Sprintf("%v", str), fmt.Sprintf("%v", substr)), nil
 	},
 	"slice": func(val interface{}, start interface{}, end interface{}) (interface{}, error) {
-		v := fmt.Sprintf("%v", val)
-		s := int(start.(int))
-		e := int(end.(int))
-		if s < 0 {
-			s += len(v)
+		// Start and end values
+		var s, e int
+		switch tmp := start.(type) {
+		case int:
+			s = tmp
+		default:
+			return nil, fmt.Errorf("int expeted for 2nd parameter %v", tmp)
 		}
-		if e < 0 {
-			e += len(v)
+		switch tmp := end.(type) {
+		case int:
+			e = tmp
+		default:
+			return nil, fmt.Errorf("int expeted for 3rd parameter %v", tmp)
+		}
+
+		// string or array
+		switch v := val.(type) {
+		case string:
+			if s < 0 {
+				s += len(v)
+			}
+			if e < 0 {
+				e += len(v)
+			}
+			return v[s:e], nil
+		case []interface{}:
+			if s < 0 {
+				s += len(v)
+			}
+			if e < 0 {
+				e += len(v)
+			}
+			return v[s:e], nil
 		}
-		return v[s:e], nil
+		return nil, fmt.Errorf("not an array")
 	},
 }

clab/config/template_test.go

@@ -0,0 +1,40 @@
+package config
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestFuncMapDefault(t *testing.T) {
+
+	// parameters & return
+	tSet := map[string][][]interface{}{
+		"default": {
+			{nil, 1, 1},
+			{5, 1, 5},
+			{"", "1", "1"},
+			{nil, nil, fmt.Errorf("")},
+		},
+		"contains": {
+			{"aa.", ".", true},
+			{"ss", ".", false},
+		}}
+
+	for name, set := range tSet {
+		fn := funcMap[name].(func(interface{}, interface{}) (interface{}, error))
+
+		for _, p := range set {
+			exp := p[len(p)-1]
+			var expe error
+			switch v := exp.(type) {
+			case error:
+				expe = v
+				exp = nil
+			}
+			res, err := fn(p[0], p[1])
+			if res != exp || (err != nil && expe == nil) {
+				t.Errorf("%v expected %v got %v error %v err: %v", p, exp, res, expe, err)
+			}
+		}
+	}
+}

lab-examples/vr05/conf1.clab.yml

@@ -29,10 +29,11 @@ topology:
       labels:
         port: 1/1/c1/1, 1/1/c2/1
         ip: 1.1.1.2/30
-        vlan: 99
+        vlan: "99, 99"
     - endpoints: [sr2:eth1, sr3:eth2]
       labels:
-        port: 1/1/c1/1, 1/1/c2/1
+        port: 1/1/c1/1, 1/1/c2/1ssh
+        vlan: 98
     - endpoints: [sr3:eth1, sr4:eth2]
       labels:
         port: 1/1/c1/1, 1/1/c2/1