refactor: switch to CheckType enum

cmd/portpatrol/main.go

@@ -14,7 +14,7 @@ import (
 	"github.com/containeroo/portpatrol/internal/runner"
 )
 
-const version = "0.4.4"
+const version = "0.4.5"
 
 // run is the main function of the application
 func run(ctx context.Context, getEnv func(string) string, output io.Writer) error {

cmd/portpatrol/main_test.go

@@ -206,7 +206,7 @@ func TestRun(t *testing.T) {
 			t.Error("Expected error, got none")
 		}
 
-		expected := "configuration error: unsupported check type: invalid"
+		expected := "configuration error: invalid check type from environment: unsupported check type: invalid"
 		if err.Error() != expected {
 			t.Errorf("Expected error to contain %q, got %q", expected, err.Error())
 		}
@@ -237,7 +237,7 @@ func TestRun(t *testing.T) {
 			t.Error("Expected error, got none")
 		}
 
-		expected := "configuration error: could not infer check type for address htp://localhost:8080: unsupported scheme: htp"
+		expected := "configuration error: could not infer check type from address htp://localhost:8080: unsupported check type: htp"
 		if err.Error() != expected {
 			t.Errorf("Expected error to contain %q, got %q", expected, err.Error())
 		}

internal/checker/checker.go

@@ -7,11 +7,18 @@ import (
 	"time"
 )
 
-// SupportedCheckTypes maps check types to their supported schemes.
-var SupportedCheckTypes = map[string][]string{
-	"http": {"http", "https"},
-	"tcp":  {"tcp"},
-	"icmp": {"icmp"},
+// CheckType is an enumeration that represents the type of check being performed.
+type CheckType int
+
+const (
+	TCP  CheckType = iota // TCP represents a check over the TCP protocol.
+	HTTP                  // HTTP represents a check over the HTTP protocol.
+	ICMP                  // ICMP represents a check using the ICMP protocol (ping).
+)
+
+// String returns the string representation of the CheckType.
+func (c CheckType) String() string {
+	return [...]string{"TCP", "HTTP", "ICMP"}[c]
 }
 
 // Checker is an interface that defines methods to perform a check.
@@ -21,47 +28,29 @@ type Checker interface {
 }
 
 // Factory function that returns the appropriate Checker based on checkType
-func NewChecker(checkType, name, address string, timeout time.Duration, getEnv func(string) string) (Checker, error) {
+func NewChecker(checkType CheckType, name, address string, timeout time.Duration, getEnv func(string) string) (Checker, error) {
 	switch checkType {
-	case "http", "https":
-		// HTTP and HTTPS checkers may need environment variables for proxy settings, etc.
+	case HTTP: // HTTP and HTTPS checkers may need environment variables for proxy settings, etc.
 		return NewHTTPChecker(name, address, timeout, getEnv)
-	case "tcp":
-		// TCP checkers may not need environment variables
+	case TCP: // TCP checkers may not need environment variables
 		return NewTCPChecker(name, address, timeout)
-	case "icmp":
-		// ICMP checkers may have a different timeout logic
+	case ICMP: // ICMP checkers may have a different timeout logic
 		return NewICMPChecker(name, address, timeout, getEnv)
 	default:
-		return nil, fmt.Errorf("unsupported check type: %s", checkType)
+		return nil, fmt.Errorf("unsupported check type: %d", checkType)
 	}
 }
 
-// IsValidCheckType validates if the check type is supported.
-func IsValidCheckType(checkType string) bool {
-	_, exists := SupportedCheckTypes[checkType]
-
-	return exists
-}
-
-// InferCheckType infers the check type based on the scheme of the target address.
-// It returns an empty string and no error if no scheme is provided.
-// If an unsupported scheme is provided, it returns an error.
-func InferCheckType(address string) (string, error) {
-	scheme, _ := extractScheme(address)
-	if scheme == "" {
-		return "", nil
-	}
-
-	scheme = strings.ToLower(scheme) // Normalize the scheme to lowercase
-
-	for checkType, schemes := range SupportedCheckTypes {
-		for _, s := range schemes {
-			if s == scheme {
-				return checkType, nil
-			}
-		}
+// GetCheckTypeFromString converts a string to a CheckType enum.
+func GetCheckTypeFromString(checkTypeStr string) (CheckType, error) {
+	switch strings.ToLower(checkTypeStr) {
+	case "http", "https":
+		return HTTP, nil
+	case "tcp":
+		return TCP, nil
+	case "icmp":
+		return ICMP, nil
+	default:
+		return -1, fmt.Errorf("unsupported check type: %s", checkTypeStr)
 	}
-
-	return "", fmt.Errorf("unsupported scheme: %s", scheme)
 }

internal/checker/checker_test.go

@@ -11,7 +11,7 @@
 	t.Run("Valid HTTP checker", func(t *testing.T) {
 		t.Parallel()
 
-		check, err := NewChecker("http", "example", "http://example.com", 5*time.Second, func(s string) string {
+		check, err := NewChecker(HTTP, "example", "http://example.com", 5*time.Second, func(s string) string {
 			return ""
 		})
 		if err != nil {
@@ -27,7 +27,7 @@
 	t.Run("Valid TCP checker", func(t *testing.T) {
 		t.Parallel()
 
-		check, err := NewChecker("tcp", "example", "example.com:80", 5*time.Second, func(s string) string {
+		check, err := NewChecker(TCP, "example", "example.com:80", 5*time.Second, func(s string) string {
 			return ""
 		})
 		if err != nil {
@@ -43,7 +43,7 @@
 	t.Run("Valid ICMP checker", func(t *testing.T) {
 		t.Parallel()
 
-		check, err := NewChecker("icmp", "example", "example.com", 5*time.Second, func(s string) string {
+		check, err := NewChecker(ICMP, "example", "example.com", 5*time.Second, func(s string) string {
 			return ""
 		})
 		if err != nil {
@@ -59,130 +59,69 @@
 	t.Run("Invalid checker type", func(t *testing.T) {
 		t.Parallel()
 
-		_, err := NewChecker("invalid", "example", "example.com", 5*time.Second, func(s string) string {
+		_, err := NewChecker(8, "example", "example.com", 5*time.Second, func(s string) string {
 			return ""
 		})
 		if err == nil {
 			t.Fatal("expected an error, got none")
 		}
 
-		expected := "unsupported check type: invalid"
+		expected := "unsupported check type: 8"
 		if err.Error() != expected {
 			t.Errorf("expected error to be %q, got %q", expected, err.Error())
 		}
 	})
 }
 
-func TestIsValidCheckType(t *testing.T) {
+func TestGetCheckTypeString(t *testing.T) {
 	t.Parallel()
 
-	t.Run("Valid TCP Check Type", func(t *testing.T) {
+	t.Run("Check type string (enum)", func(t *testing.T) {
 		t.Parallel()
 
-		if isValid := IsValidCheckType("tcp"); !isValid {
-			t.Errorf("expected true for check type 'tcp', got false")
+		if HTTP.String() != "HTTP" {
+			t.Fatalf("expected 'HTTP', got %q", HTTP.String())
 		}
-	})
-
-	t.Run("Valid HTTP Check Type", func(t *testing.T) {
-		t.Parallel()
-
-		if isValid := IsValidCheckType("http"); !isValid {
-			t.Errorf("expected true for check type 'http', got false")
-		}
-	})
-
-	t.Run("Invalid Check Type", func(t *testing.T) {
-		t.Parallel()
-
-		if isValid := IsValidCheckType("invalid"); isValid {
-			t.Errorf("expected false for check type 'invalid', got true")
-		}
-	})
-
-	t.Run("Empty Check Type", func(t *testing.T) {
-		t.Parallel()
-
-		if isValid := IsValidCheckType(""); isValid {
-			t.Errorf("expected false for empty check type, got true")
-		}
-	})
-
-	t.Run("Random String Check Type", func(t *testing.T) {
-		t.Parallel()
-
-		if isValid := IsValidCheckType("random"); isValid {
-			t.Errorf("expected false for check type 'random', got true")
-		}
-	})
-}
-
-func TestInferCheckType(t *testing.T) {
-	t.Parallel()
-
-	t.Run("HTTP scheme", func(t *testing.T) {
-		t.Parallel()
-
-		checkType, err := InferCheckType("http://example.com")
-		if err != nil {
-			t.Fatalf("expected no error, got %q", err)
+		if TCP.String() != "TCP" {
+			t.Fatalf("expected 'TCP', got %q", TCP.String())
 		}
-
-		if checkType != "http" {
-			t.Fatalf("expected 'http', got %q", checkType)
+		if ICMP.String() != "ICMP" {
+			t.Fatalf("expected 'ICMP', got %q", ICMP.String())
 		}
 	})
 
-	t.Run("TCP scheme", func(t *testing.T) {
-		t.Parallel()
-
-		checkType, err := InferCheckType("tcp://example.com")
+	t.Run("Check type string (func)", func(t *testing.T) {
+		want := HTTP
+		got, err := GetCheckTypeFromString("http")
 		if err != nil {
 			t.Fatalf("expected no error, got %q", err)
 		}
-
-		if checkType != "tcp" {
-			t.Fatalf("expected 'tcp', got %q", checkType)
+		if want != got {
+			t.Fatalf("expected %q, got %q", want, got)
 		}
-	})
-
-	t.Run("ICMP scheme", func(t *testing.T) {
-		t.Parallel()
 
-		checkType, err := InferCheckType("icmp://host.example.com")
+		want = TCP
+		got, err = GetCheckTypeFromString("tcp")
 		if err != nil {
 			t.Fatalf("expected no error, got %q", err)
 		}
-
-		if checkType != "icmp" {
-			t.Fatalf("expected 'http', got %q", checkType)
+		if want != got {
+			t.Fatalf("expected %q, got %q", want, got)
 		}
-	})
-
-	t.Run("No scheme", func(t *testing.T) {
-		t.Parallel()
 
-		checkType, err := InferCheckType("example.com:80")
+		want = ICMP
+		got, err = GetCheckTypeFromString("icmp")
 		if err != nil {
 			t.Fatalf("expected no error, got %q", err)
 		}
-
-		if checkType != "" {
-			t.Fatalf("expected 'tcp', got %q", checkType)
+		if want != got {
+			t.Fatalf("expected %q, got %q", want, got)
 		}
-	})
 
-	t.Run("Unsupported scheme", func(t *testing.T) {
-		t.Parallel()
-
-		_, err := InferCheckType("ftp://example.com")
+		want = -1
+		got, err = GetCheckTypeFromString("invalid")
 		if err == nil {
 			t.Fatal("expected an error, got none")
 		}
-
-		expected := "unsupported scheme: ftp"
-		if err.Error() != expected {
-			t.Errorf("expected error to be %q, got %q", expected, err.Error())
-		}
 	})
 }