oem: refactor the config

- Seperate the config from File()
- Add YAML tags for the fields

system/oem.go

@@ -0,0 +1,32 @@
+package system
+
+import (
+	"fmt"
+	"path"
+
+	"github.com/coreos/coreos-cloudinit/config"
+)
+
+// OEM is a top-level structure which embeds its underlying configuration,
+// config.OEM, and provides the system-specific File().
+type OEM struct {
+	config.OEM
+}
+
+func (oem OEM) File(_ string) (*File, error) {
+	if oem.ID == "" {
+		return nil, nil
+	}
+
+	content := fmt.Sprintf("ID=%s\n", oem.ID)
+	content += fmt.Sprintf("VERSION_ID=%s\n", oem.VersionID)
+	content += fmt.Sprintf("NAME=%q\n", oem.Name)
+	content += fmt.Sprintf("HOME_URL=%q\n", oem.HomeURL)
+	content += fmt.Sprintf("BUG_REPORT_URL=%q\n", oem.BugReportURL)
+
+	return &File{
+		Path:               path.Join("etc", "oem-release"),
+		RawFilePermissions: "0644",
+		Content:            content,
+	}, nil
+}

system/oem_test.go

@@ -0,0 +1,47 @@
+package system
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/coreos/coreos-cloudinit/config"
+)
+
+func TestOEMFile(t *testing.T) {
+	for _, tt := range []struct {
+		config config.OEM
+		file   *File
+	}{
+		{
+			config.OEM{},
+			nil,
+		},
+		{
+			config.OEM{
+				ID:           "rackspace",
+				Name:         "Rackspace Cloud Servers",
+				VersionID:    "168.0.0",
+				HomeURL:      "https://www.rackspace.com/cloud/servers/",
+				BugReportURL: "https://github.com/coreos/coreos-overlay",
+			},
+			&File{
+				Path:               "etc/oem-release",
+				RawFilePermissions: "0644",
+				Content: `ID=rackspace
+VERSION_ID=168.0.0
+NAME="Rackspace Cloud Servers"
+HOME_URL="https://www.rackspace.com/cloud/servers/"
+BUG_REPORT_URL="https://github.com/coreos/coreos-overlay"
+`,
+			},
+		},
+	} {
+		file, err := OEM{tt.config}.File("")
+		if err != nil {
+			t.Errorf("bad error (%q): want %q, got %q", tt.config, nil, err)
+		}
+		if !reflect.DeepEqual(tt.file, file) {
+			t.Errorf("bad file (%q): want %#v, got %#v", tt.config, tt.file, file)
+		}
+	}
+}