elasticsearch: Fix broken diagnostics command (#110)

Fixes the broken diagnostics command by using `os.Create` rather than
`os.Open` for the .zip bundled file. Additionally adds a notee about a
potentially necessary timeout increase in order to complete the
operation.

Signed-off-by: Marc Lopez <marc5.12@outlook.com>

Author: marclop

cmd/deployment/elasticsearch/diagnose.go

@@ -33,13 +33,14 @@ import (
 var generateElasticsearchDiagnosticsCmd = &cobra.Command{
 	Use:     "diagnose <cluster id>",
 	Short:   "Generates a diagnostics bundle for the cluster",
+	Long:    "Generates a diagnostics bundle for the cluster, a timeout increase might be necessary",
 	PreRunE: cmdutil.MinimumNArgsAndUUID(1),
 	RunE: func(cmd *cobra.Command, args []string) error {
 		location := cmd.Flag("location").Value.String()
 		filename := fmt.Sprint("diagnostic-", args[0], ".zip")
 		path := filepath.Join(location, filename)
 
-		f, err := os.Open(path)
+		f, err := os.Create(path)
 		if err != nil {
 			return err
 		}

docs/ecctl_deployment_elasticsearch_diagnose.md

@@ -4,7 +4,7 @@ Generates a diagnostics bundle for the cluster
 
 ### Synopsis
 
-Generates a diagnostics bundle for the cluster
+Generates a diagnostics bundle for the cluster, a timeout increase might be necessary
 
 ```
 ecctl deployment elasticsearch diagnose <cluster id> [flags]