Add OutOfRangeError and handle it properly

Author: epapbak

types/conversion.go

@@ -14,15 +14,14 @@
 
 package types
 
-import (
-	"errors"
-)
-
 // Uint64ToUint32 safely converts a uint64 into a uint32 without overflow
 func Uint64ToUint32(v uint64) (uint32, error) {
 	// Check for overflow without casting
 	if v > uint64(^uint32(0)) { // ^uint32(0) is the maximum uint32 value (4,294,967,295)
-		return 0, errors.New("value exceeds uint32 range")
+		return 0, &OutOfRangeError{
+			Value: v,
+			Type:  "uint32",
+		}
 	}
 
 	return uint32(v), nil // #nosec G103: safe after bounds check

types/conversion_test.go

@@ -22,24 +22,35 @@ func TestUint64ToUint32(t *testing.T) {
 		name    string
 		input   uint64
 		want    uint32
-		wantErr bool
+		errType error
 	}{
-		{"Zero", 0, 0, false},
-		{"Max uint32", 4294967295, 4294967295, false},
-		{"Overflow", 4294967296, 0, true},
-		{"Large overflow", 18446744073709551615, 0, true},
-		{"Mid-range value", 2147483648, 2147483648, false},
+		{"Zero", 0, 0, nil},
+		{"Max uint32", 4294967295, 4294967295, nil},
+		{"Overflow", 4294967296, 0, &OutOfRangeError{}},
+		{"Large overflow", 18446744073709551615, 0, &OutOfRangeError{}},
+		{"Mid-range value", 2147483648, 2147483648, nil},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			got, err := Uint64ToUint32(tt.input)
-			if (err != nil) != tt.wantErr {
-				t.Errorf("Uint64ToUint32() error = %v, wantErr %v", err, tt.wantErr)
-				return
-			}
-			if got != tt.want {
-				t.Errorf("Uint64ToUint32() = %v, want %v", got, tt.want)
+			if tt.errType != nil {
+				// Check if the error is of the expected type
+				if err == nil {
+					t.Errorf("Expected error type %T, got no error", tt.errType)
+				} else if _, ok := err.(interface{ Error() string }); !ok {
+					t.Errorf("Expected error type %T, got %T", tt.errType, err)
+				} else if _, ok := err.(*OutOfRangeError); !ok {
+					t.Errorf("Expected error type *OutOfRangeError, got %T", err)
+				}
+			} else {
+				if err != nil {
+					t.Errorf("Uint64ToUint32() error = %v, want no error", err)
+					return
+				}
+				if got != tt.want {
+					t.Errorf("Uint64ToUint32() = %v, want %v", got, tt.want)
+				}
 			}
 		})
 	}

types/errors.go

@@ -106,14 +106,25 @@ func (e *ValidationError) Error() string {
 	)
 }
 
+// OutOfRangeError indicates that a value is outside the expected range.
+type OutOfRangeError struct {
+	Value uint64
+	Type  string
+}
+
+// Error returns a formatted error string for the OutOfRangeError.
+func (e *OutOfRangeError) Error() string {
+	return fmt.Sprintf("value %d out of range for %s", e.Value, e.Type)
+}
+
 // HandleServerError handles separate server errors and sends appropriate responses
 func HandleServerError(writer http.ResponseWriter, err error) {
 	var level = log.Warn() // set the default log level for most HTTP responses
 
 	var respErr error
 
 	switch err := err.(type) {
-	case *RouterMissingParamError, *RouterParsingError, *json.SyntaxError, *NoBodyError, *ValidationError:
+	case *RouterMissingParamError, *RouterParsingError, *json.SyntaxError, *NoBodyError, *ValidationError, *OutOfRangeError:
 		respErr = responses.SendBadRequest(writer, err.Error())
 	case *json.UnmarshalTypeError:
 		respErr = responses.SendBadRequest(writer, "bad type in json data")