feat: Add save config feature within the config subcommand (#315)

Summary:
Pull Request resolved: #315

Calnex builds a desired config by applying changes to the original config fetched from the device. If anything is updated, it will print the diff.

This feature allows users to show the entire config and not only the diff, even if there are no changes to the config. Which might be useful for debugging.

It is done by adding a --save <PATH> flag to Calnex's config subcommand. When --save <PATH> is provided, Calnex will dump the config file to <PATH>. Note that --save and --apply is mutually exclusive so either none is provided or one of the two.

Reviewed By: leoleovich

Differential Revision: D52538805

fbshipit-source-id: 25ba33331655e9fefdee9dfc57c8c453434c7470

calnex/cmd/cmd.go

@@ -36,6 +36,7 @@ var (
 	insecureTLS bool
 	source      string
 	target      string
+	saveConfig  string
 )
 
 // Execute is the main entry point for CLI interface

calnex/cmd/config.go

@@ -32,12 +32,14 @@ func init() {
 	configCmd.Flags().BoolVar(&insecureTLS, "insecureTLS", false, "Ignore TLS certificate errors")
 	configCmd.Flags().StringVar(&target, "target", "", "device to configure")
 	configCmd.Flags().StringVar(&source, "file", "", "configuration file")
+	configCmd.Flags().StringVar(&saveConfig, "save", "", "save configuration to the specified path")
 	if err := configCmd.MarkFlagRequired("target"); err != nil {
 		log.Fatal(err)
 	}
 	if err := configCmd.MarkFlagRequired("file"); err != nil {
 		log.Fatal(err)
 	}
+	configCmd.MarkFlagsMutuallyExclusive("apply", "save")
 }
 
 var configCmd = &cobra.Command{
@@ -65,8 +67,14 @@ var configCmd = &cobra.Command{
 			log.Fatalf("Failed to find config for %s in %s", target, source)
 		}
 
-		if err := config.Config(target, insecureTLS, dc, apply); err != nil {
-			log.Fatal(err)
+		if saveConfig != "" {
+			if err := config.Save(target, insecureTLS, dc, saveConfig); err != nil {
+				log.Fatal(err)
+			}
+		} else {
+			if err := config.Config(target, insecureTLS, dc, apply); err != nil {
+				log.Fatal(err)
+			}
 		}
 	},
 }

calnex/config/config.go

@@ -193,20 +193,12 @@ func Config(target string, insecureTLS bool, cc *CalnexConfig, apply bool) error
 	var c config
 	api := api.NewAPI(target, insecureTLS)
 
-	f, err := api.FetchSettings()
+	f, err := prepare(&c, api, target, cc)
+
 	if err != nil {
 		return err
 	}
 
-	m := f.Section("measure")
-	g := f.Section("gnss")
-
-	// set base config
-	c.baseConfig(m, g, target, cc.AntennaDelayNS)
-
-	// set measure config
-	c.measureConfig(m, cc.Measure)
-
 	if !apply {
 		log.Info("dry run. Exiting")
 		return nil
@@ -246,3 +238,41 @@ func Config(target string, insecureTLS bool, cc *CalnexConfig, apply bool) error
 
 	return nil
 }
+
+// Save saves the Network/Calnex configs to file
+func Save(target string, insecureTLS bool, cc *CalnexConfig, saveConfig string) error {
+	var c config
+	api := api.NewAPI(target, insecureTLS)
+
+	f, err := prepare(&c, api, target, cc)
+
+	if err != nil {
+		return err
+	}
+
+	err = f.SaveTo(saveConfig)
+
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func prepare(c *config, api *api.API, target string, cc *CalnexConfig) (*ini.File, error) {
+	f, err := api.FetchSettings()
+	if err != nil {
+		return nil, err
+	}
+
+	m := f.Section("measure")
+	g := f.Section("gnss")
+
+	// set base config
+	c.baseConfig(m, g, target, cc.AntennaDelayNS)
+
+	// set measure config
+	c.measureConfig(m, cc.Measure)
+
+	return f, nil
+}