SEBA-580 cordctl CLI for XOS

Change-Id: I807821a12d3d0fe4aee89791e2fe46e973da8eda
diff --git a/commands/services.go b/commands/services.go
new file mode 100644
index 0000000..a38c469
--- /dev/null
+++ b/commands/services.go
@@ -0,0 +1,114 @@
+/*
+ * Portions copyright 2019-present Open Networking Foundation
+ * Original copyright 2019-present Ciena Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package commands
+
+import (
+	"context"
+	"github.com/fullstorydev/grpcurl"
+	flags "github.com/jessevdk/go-flags"
+	"github.com/jhump/protoreflect/dynamic"
+	"github.com/opencord/cordctl/format"
+)
+
+const (
+	DEFAULT_SERVICE_FORMAT = "table{{ .Name }}\t{{.Version}}\t{{.State}}"
+)
+
+type ServiceList struct {
+	OutputOptions
+}
+
+type ServiceListOutput struct {
+	Name    string `json:"name"`
+	Version string `json:"version"`
+	State   string `json:"state"`
+}
+
+type ServiceOpts struct {
+	List ServiceList `command:"list"`
+}
+
+var serviceOpts = ServiceOpts{}
+
+func RegisterServiceCommands(parser *flags.Parser) {
+	parser.AddCommand("service", "service commands", "Commands to query and manipulate dynamically loaded XOS Services", &serviceOpts)
+}
+
+func (options *ServiceList) Execute(args []string) error {
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetReflectionMethod(conn, "xos.dynamicload.GetLoadStatus")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	headers := GenerateHeaders()
+
+	h := &RpcEventHandler{}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, headers, h, h.GetParams)
+	if err != nil {
+		return err
+	}
+
+	if h.Status != nil && h.Status.Err() != nil {
+		return h.Status.Err()
+	}
+
+	d, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return err
+	}
+
+	items, err := d.TryGetFieldByName("services")
+	if err != nil {
+		return err
+	}
+
+	outputFormat := CharReplacer.Replace(options.Format)
+	if outputFormat == "" {
+		outputFormat = DEFAULT_SERVICE_FORMAT
+	}
+	if options.Quiet {
+		outputFormat = "{{.Id}}"
+	}
+
+	data := make([]ServiceListOutput, len(items.([]interface{})))
+
+	for i, item := range items.([]interface{}) {
+		val := item.(*dynamic.Message)
+		data[i].Name = val.GetFieldByName("name").(string)
+		data[i].Version = val.GetFieldByName("version").(string)
+		data[i].State = val.GetFieldByName("state").(string)
+	}
+
+	result := CommandResult{
+		Format:   format.Format(outputFormat),
+		OutputAs: toOutputType(options.OutputAs),
+		Data:     data,
+	}
+
+	GenerateOutput(&result)
+	return nil
+}