matchbox/http: Update grub endpoint to use profile kernel args

Documentation/network-setup.md

@@ -57,7 +57,18 @@ You can chainload from a menu entry or use other [iPXE commands](http://ipxe.org
 
 ## GRUB
 
-Needs docs.
+Needs more docs.
+
+`grub-mknetdir --net-directory=/var/lib/tftpboot`
+
+/var/lib/tftpboot/boot/grub/grub.cfg:
+```ini
+insmod i386-pc/http.mod
+set root=http,matchbox.foo:8080
+configfile /grub
+```
+
+Make sure to replace variables in the example config files; instead of iPXE variables, use GRUB variables. Check the [GRUB2 manual](https://www.gnu.org/software/grub/manual/grub.html#Network).
 
 ### Configuring DHCP
 

matchbox/http/grub.go

@@ -10,12 +10,19 @@ import (
 )
 
 var grubTemplate = template.Must(template.New("GRUB2 config").Parse(`default=0
+fallback=1
 timeout=1
-menuentry "CoreOS" {
+menuentry "CoreOS (EFI)" {
 echo "Loading kernel"
-linuxefi "{{.Kernel}}"{{range $key, $value := .Cmdline}} {{if $value}}"{{$key}}={{$value}}"{{else}}"{{$key}}"{{end}}{{end}}
+linuxefi "{{.Kernel}}"{{range $arg := .Args}} {{$arg}}{{end}}{{range $key, $value := .Cmdline}} {{if $value}}"{{$key}}={{$value}}"{{else}}"{{$key}}"{{end}}{{end}}
 echo "Loading initrd"
-initrdefi {{ range $element := .Initrd }}"{{$element}}" {{end}}
+initrdefi {{ range $element := .Initrd }} "{{$element}}"{{end}}
+}
+menuentry "CoreOS (BIOS)" {
+echo "Loading kernel"
+linux "{{.Kernel}}"{{range $arg := .Args}} {{$arg}}{{end}}{{range $key, $value := .Cmdline}} {{if $value}}"{{$key}}={{$value}}"{{else}}"{{$key}}"{{end}}{{end}}
+echo "Loading initrd"
+initrd {{ range $element := .Initrd }} "{{$element}}"{{end}}
 }
 `))
 

matchbox/http/grub_test.go

@@ -0,0 +1,43 @@
+package http
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"context"
+	logtest "github.com/Sirupsen/logrus/hooks/test"
+	"github.com/stretchr/testify/assert"
+
+	fake "github.com/coreos/matchbox/matchbox/storage/testfakes"
+)
+
+func TestGrubHandler(t *testing.T) {
+	logger, _ := logtest.NewNullLogger()
+	srv := NewServer(&Config{Logger: logger})
+	h := srv.grubHandler()
+	ctx := withProfile(context.Background(), fake.Profile)
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/", nil)
+	h.ServeHTTP(ctx, w, req)
+	// assert that:
+	// - the Profile's NetBoot config is rendered as a GRUB2 config
+	expectedScript := `default=0
+fallback=1
+timeout=1
+menuentry "CoreOS (EFI)" {
+echo "Loading kernel"
+linuxefi "/image/kernel" a=b c
+echo "Loading initrd"
+initrdefi  "/image/initrd_a" "/image/initrd_b"
+}
+menuentry "CoreOS (BIOS)" {
+echo "Loading kernel"
+linux "/image/kernel" a=b c
+echo "Loading initrd"
+initrd  "/image/initrd_a" "/image/initrd_b"
+}
+`
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, expectedScript, w.Body.String())
+}