Custom pongo2 filters for loading haproxy data.

pkg/controller/ingress/parser.go

@@ -13,6 +13,7 @@ import (
 	"github.com/flosch/pongo2"
 	kapi "k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/util/intstr"
+	"github.com/appscode/voyager/pkg/controller/ingress/template"
 )
 
 func (lbc *EngressController) parse() error {
@@ -97,13 +98,13 @@ func (lbc *EngressController) getEndpoints(s *kapi.Service, servicePort *kapi.Se
 }
 
 func (lbc *EngressController) generateTemplate() error {
-	log.Infoln("Generating Ingress templates.")
+	log.Infoln("Generating Ingress template.")
 	ctx, err := Context(lbc.Parsed)
 	if err != nil {
 		return errors.New().WithCause(err).Internal()
 	}
 
-	tpl, err := pongo2.FromString(haproxyTemplate)
+	tpl, err := pongo2.FromString(template.HAProxyTemplate)
 	if err != nil {
 		return errors.New().WithCause(err).Internal()
 	}

pkg/controller/ingress/template/filters.go

@@ -0,0 +1,39 @@
+package template
+
+import (
+	"strings"
+
+	"github.com/flosch/pongo2"
+)
+
+// custom pongo2 filters to works with
+func init() {
+	pongo2.RegisterFilter("header_name", HeaderNameFilter)
+	pongo2.RegisterFilter("host_name", HostNameFilter)
+}
+
+func HeaderNameFilter(in *pongo2.Value, param *pongo2.Value) (*pongo2.Value, *pongo2.Error) {
+	v := strings.TrimSpace(in.String())
+	if v == "" {
+		return pongo2.AsValue(v), nil
+	}
+	index := strings.Index(v, " ")
+	if index < 0 {
+		return pongo2.AsValue(""), nil
+	}
+	name := v[:index]
+	return pongo2.AsValue(name), nil
+}
+
+func HostNameFilter(in *pongo2.Value, param *pongo2.Value) (*pongo2.Value, *pongo2.Error) {
+	v := in.String()
+	v = strings.TrimSpace(v)
+	if v == "" {
+		return pongo2.AsValue(v), nil
+	}
+	if strings.HasPrefix(v, "*") {
+		v = v[1:]
+		return pongo2.AsValue("hdr_end(host) -i " + v), nil
+	}
+	return pongo2.AsValue("hdr(host) -i " + v), nil
+}

pkg/controller/ingress/template/filters_test.go

@@ -0,0 +1,57 @@
+package template
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/flosch/pongo2"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHeaderNameFilter(t *testing.T) {
+	temp := `
+{{ val|header_name }}
+{{ val2|header_name }}
+	`
+	ctx := &pongo2.Context{
+		"val":  "hello world",
+		"val2": "hello   world",
+	}
+	res, _ := render(ctx, temp)
+	exp := `
+hello
+hello
+	`
+	assert.Equal(t, res, exp)
+	fmt.Println(res)
+}
+
+func TestHostNameFilter(t *testing.T) {
+	temp := `
+{{ val|host_name }}
+{{ val2|host_name }}
+	`
+	ctx := &pongo2.Context{
+		"val":  "appscode.com",
+		"val2": "*.appscode.com",
+	}
+	res, _ := render(ctx, temp)
+	exp := `
+hdr(host) -i appscode.com
+hdr_end(host) -i .appscode.com
+	`
+	assert.Equal(t, res, exp)
+	fmt.Println(res)
+}
+
+func render(ctx *pongo2.Context, temp string) (string, error) {
+	tpl, err := pongo2.FromString(temp)
+	if err != nil {
+		return "", err
+	}
+	out, err := tpl.Execute(*ctx)
+	if err != nil {
+		return "", err
+	}
+	return out, nil
+}

pkg/controller/ingress/template.go → pkg/controller/ingress/template/template.go

@@ -1,6 +1,6 @@
-package ingress
+package template
 
-const haproxyTemplate = `# This file uses golang pongo2 templates to
+const HAProxyTemplate = `# This file uses golang pongo2 template to
 # dynamically configure the haproxy loadbalancer.
 global
     daemon