Improve template extraction (#49)

Functions to extract templates from a thing and a dashboard does not return errors anymore (they're not needed).
Default template filenames have been changed: whitespaces are stripped and a suffix '-thing' or '-dashboard' has been added.
Destination files are now logged. 

* Remove useless error parameter
* Strip spaces from extracted template names
* Extraction: Log destination file

Author: Paolo Calao

Diff for: command/dashboard/extract.go

@@ -25,6 +25,7 @@ import (
 	"github.com/arduino/arduino-cloud-cli/internal/config"
 	"github.com/arduino/arduino-cloud-cli/internal/iot"
 	"github.com/arduino/arduino-cloud-cli/internal/template"
+	"github.com/sirupsen/logrus"
 )
 
 // ExtractParams contains the parameters needed to
@@ -58,20 +59,19 @@ func Extract(params *ExtractParams) error {
 		return err
 	}
 
-	templ, err := template.FromDashboard(dashboard)
-	if err != nil {
-		return err
-	}
+	templ := template.FromDashboard(dashboard)
 
 	if params.Outfile == nil {
 		name, ok := templ["name"].(string)
 		if name == "" || !ok {
 			return errors.New("dashboard template does not have a valid name")
 		}
-		outfile := name + "-dashboard" + "." + params.Format
+		name = strings.Join(strings.Fields(name), "")
+		outfile := name + "-dashboard." + params.Format
 		params.Outfile = &outfile
 	}
 
+	logrus.Infof("Extracting template in file: %s", *params.Outfile)
 	err = template.ToFile(templ, *params.Outfile, params.Format)
 	if err != nil {
 		return fmt.Errorf("saving template: %w", err)

Diff for: command/thing/extract.go

@@ -25,6 +25,7 @@ import (
 	"github.com/arduino/arduino-cloud-cli/internal/config"
 	"github.com/arduino/arduino-cloud-cli/internal/iot"
 	"github.com/arduino/arduino-cloud-cli/internal/template"
+	"github.com/sirupsen/logrus"
 )
 
 // ExtractParams contains the parameters needed to
@@ -58,20 +59,19 @@ func Extract(params *ExtractParams) error {
 		return err
 	}
 
-	templ, err := template.FromThing(thing)
-	if err != nil {
-		return err
-	}
+	templ := template.FromThing(thing)
 
 	if params.Outfile == nil {
 		name, ok := templ["name"].(string)
 		if name == "" || !ok {
 			return errors.New("thing template does not have a valid name")
 		}
-		outfile := name + "." + params.Format
+		name = strings.Join(strings.Fields(name), "")
+		outfile := name + "-thing." + params.Format
 		params.Outfile = &outfile
 	}
 
+	logrus.Infof("Extracting template in file: %s", *params.Outfile)
 	err = template.ToFile(templ, *params.Outfile, params.Format)
 	if err != nil {
 		return fmt.Errorf("saving template: %w", err)

Diff for: internal/template/extract.go

@@ -29,7 +29,7 @@ import (
 )
 
 // FromThing extracts a template of type map[string]interface{} from a thing.
-func FromThing(thing *iotclient.ArduinoThing) (map[string]interface{}, error) {
+func FromThing(thing *iotclient.ArduinoThing) map[string]interface{} {
 	template := make(map[string]interface{})
 	template["name"] = thing.Name
 
@@ -47,11 +47,11 @@ func FromThing(thing *iotclient.ArduinoThing) (map[string]interface{}, error) {
 	}
 	template["variables"] = props
 
-	return template, nil
+	return template
 }
 
 // FromDashboard extracts a template of type map[string]interface{} from a dashboard.
-func FromDashboard(dashboard *iotclient.ArduinoDashboardv2) (map[string]interface{}, error) {
+func FromDashboard(dashboard *iotclient.ArduinoDashboardv2) map[string]interface{} {
 	template := make(map[string]interface{})
 	template["name"] = dashboard.Name
 
@@ -94,7 +94,7 @@ func FromDashboard(dashboard *iotclient.ArduinoDashboardv2) (map[string]interfac
 	if len(widgets) > 0 {
 		template["widgets"] = widgets
 	}
-	return template, nil
+	return template
 }
 
 // ToFile takes a generic template and saves it into a file,