Now manage kubernetes version in ingress

The backend and ingressClassName are now under condition

generator/main.go

@@ -197,7 +197,7 @@ func createIngress(name string, port int, s *compose.Service) *helm.Ingress {
 				Paths: []helm.IngressPath{{
 					Path:     "/",
 					PathType: "Prefix",
-					Backend: helm.IngressBackend{
+					Backend: &helm.IngressBackend{
 						Service: helm.IngressService{
 							Name: RELEASE_NAME + "-" + name,
 							Port: map[string]interface{}{

generator/writers/ingress.go

@@ -10,7 +10,19 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
+const classAndVersionCondition = `{{- if and .Values.__name__.ingress.class (semverCompare ">=1.18-0" .Capabilities.KubeVersion.GitVersion) }}` + "\n"
+const versionCondition = `{{- if semverCompare ">=1.18-0" .Capabilities.KubeVersion.GitVersion }}` + "\n"
+
 func BuildIngress(ingress *helm.Ingress, name, templatesDir string) {
+	// Set the backend for 1.18
+	for _, b := range ingress.Spec.Rules {
+		for _, p := range b.Http.Paths {
+			p.Backend.ServiceName = p.Backend.Service.Name
+			if n, ok := p.Backend.Service.Port["number"]; ok {
+				p.Backend.ServicePort = n
+			}
+		}
+	}
 	kind := "ingress"
 	buffer := bytes.NewBuffer(nil)
 	fname := filepath.Join(templatesDir, name+"."+kind+".yaml")
@@ -23,18 +35,32 @@ func BuildIngress(ingress *helm.Ingress, name, templatesDir string) {
 	fp, _ := os.Create(fname)
 	content := string(buffer.Bytes())
 	lines := strings.Split(content, "\n")
+
+	backendHit := false
 	for _, l := range lines {
 		if strings.Contains(l, "ingressClassName") {
-			p := strings.Split(l, ":")
+			// should be set only if the version of Kubernetes is 1.18-0 or higher
-			condition := p[1]
+			cond := strings.ReplaceAll(classAndVersionCondition, "__name__", name)
-			condition = strings.ReplaceAll(condition, "'", "")
+			l = `  ` + cond + l + "\n" + `  {{- end }}`
-			condition = strings.ReplaceAll(condition, "{{", "")
-			condition = strings.ReplaceAll(condition, "}}", "")
-			condition = strings.TrimSpace(condition)
-			condition = "{{- if " + condition + " }}"
-			l = "  " + condition + "\n" + l + "\n  {{- end }}"
 		}
+
+		// manage the backend format following the Kubernetes 1.18-0 version or higher
+		if strings.Contains(l, "service:") {
+			n := CountSpaces(l)
+			l = strings.Repeat(" ", n) + versionCondition + l
+		}
+		if strings.Contains(l, "serviceName:") || strings.Contains(l, "servicePort:") {
+			n := CountSpaces(l)
+			if !backendHit {
+				l = strings.Repeat(" ", n) + "{{- else }}\n" + l
+			} else {
+				l = l + "\n" + strings.Repeat(" ", n) + "{{- end }}\n"
+			}
+			backendHit = true
+		}
+
 		fp.WriteString(l + "\n")
 	}
+
 	fp.Close()
 }

generator/writers/utils.go

@@ -0,0 +1,14 @@
+package writers
+
+// CountSpaces returns the number of spaces from the begining of the line
+func CountSpaces(line string) int {
+	var spaces int
+	for _, char := range line {
+		if char == ' ' {
+			spaces++
+		} else {
+			break
+		}
+	}
+	return spaces
+}

helm/ingress.go

@@ -38,14 +38,16 @@ type IngressHttp struct {
 type IngressPath struct {
 	Path     string
 	PathType string `yaml:"pathType"`
-	Backend  IngressBackend
+	Backend  *IngressBackend
 }
 
 type IngressBackend struct {
-	Service IngressService
+	Service     IngressService
+	ServiceName string      `yaml:"serviceName"` // for kubernetes version < 1.18
+	ServicePort interface{} `yaml:"servicePort"` // for kubernetes version < 1.18
 }
 
 type IngressService struct {
-	Name string
+	Name string                 `yaml:"name"`
-	Port map[string]interface{}
+	Port map[string]interface{} `yaml:"port"`
 }