feat: add a target URL to the welcome message (#13)

* feat: add a target URL to the welcome message (#13)

Author: agneum

main.go

@@ -29,7 +29,7 @@ func main() {
 		log.Fatalf("failed to init a query plan exporter: %v", err)
 	}
 
-	fmt.Printf("Welcome to the query plan exporter. Target: %s.\n", *target)
+	fmt.Println(generateWelcomeMessage(planner))
 
 	scannerCfg := &pgscanner.Config{
 		AutoConfirm: *autoConfirm,
@@ -38,3 +38,7 @@ func main() {
 	pgScanner := pgscanner.New(scannerCfg, os.Stdin, os.Stdout, planner)
 	pgScanner.Run(ctx)
 }
+
+func generateWelcomeMessage(planner pgscanner.PlanExporter) string {
+	return fmt.Sprintf("Welcome to the query plan exporter.\nURL: %s", planner.Target())
+}

pgscanner/pgscanner.go

@@ -22,6 +22,7 @@ const confirmationResponse = "Y"
 // PlanExporter defines the interface to post query plans.
 type PlanExporter interface {
 	Export(string) (string, error)
+	Target() string
 }
 
 // PgScanner provides a psql output scanner.

pgscanner/pgscanner_test.go

@@ -15,6 +15,10 @@ func (m Mock) Export(s string) (string, error) {
 	return m.url, m.err
 }
 
+func (m Mock) Target() string {
+	return m.url
+}
+
 func TestSuccessfulPlanPosting(t *testing.T) {
 	buf := &bytes.Buffer{}
 

visualizer/dalibo/dalibo.go

@@ -8,7 +8,7 @@ import (
 	"github.com/agneum/plan-exporter/client"
 )
 
-// visualizer constants
+// Visualizer constants.
 const (
 	VisualizerType = "dalibo"
 	defaultPostURL = "https://explain.dalibo.com/new"
@@ -40,3 +40,8 @@ func (d *Dalibo) Export(plan string) (string, error) {
 
 	return explainURL, nil
 }
+
+// Target returns a post URL.
+func (d *Dalibo) Target() string {
+	return d.postURL
+}

visualizer/depesz/depesz.go

@@ -8,7 +8,7 @@ import (
 	"github.com/agneum/plan-exporter/client"
 )
 
-// visualizer constants
+// Visualizer constants.
 const (
 	VisualizerType = "depesz"
 	defaultPostURL = "https://explain.depesz.com/"
@@ -40,3 +40,8 @@ func (d *Depesz) Export(plan string) (string, error) {
 
 	return explainURL, nil
 }
+
+// Target returns a post URL.
+func (d *Depesz) Target() string {
+	return d.postURL
+}

visualizer/tensor/tensor.go

@@ -8,7 +8,7 @@ import (
 	"github.com/agneum/plan-exporter/client"
 )
 
-// visualizer constants
+// Visualizer constants.
 const (
 	VisualizerType = "tensor"
 	defaultPostURL = "https://explain.tensor.ru/explain"
@@ -30,13 +30,18 @@ func New(postURL string) *Tensor {
 }
 
 // Export posts plan to a visualizer and returns link to the visualization plan page.
-func (d *Tensor) Export(plan string) (string, error) {
+func (t *Tensor) Export(plan string) (string, error) {
 	formVal := url.Values{planKey: []string{plan}}
 
-	explainURL, err := client.MakeRequest(d.postURL, formVal)
+	explainURL, err := client.MakeRequest(t.postURL, formVal)
 	if err != nil {
 		return "", fmt.Errorf("failed to make a request: %w", err)
 	}
 
 	return explainURL, nil
 }
+
+// Target returns a post URL.
+func (t *Tensor) Target() string {
+	return t.postURL
+}