public async Task <string> PostAsync([FromBody] TextAnalysisInput textAnalysisInput)
        {
            // Using Dependency Injected service
            var result = await _characterPositionsService.GetCharacterPositionsAsync(textAnalysisInput);

            string jsonResult = JsonConvert.SerializeObject(result, Formatting.Indented);

            return(jsonResult);
        }
        [InlineData("asdf", "df")]       // yet another valid text and subtext
        public async void GetCharacterPositionsAsync_InputIsValid_OkResult(string text, string subtext)
        {
            // Arrange
            var textAnalysisInput = new TextAnalysisInput()
            {
                Text    = text,
                Subtext = subtext
            };

            var validationResult = _fixture.Build <ValidationResult>().Create();

            validationResult.IsValid = true;

            _validationService
            .Setup(svc => svc.ValidateTextAnalysisInputAsync(It.IsAny <TextAnalysisInput>()))
            .ReturnsAsync(validationResult);

            // Act
            var result = await _characterPositionsService.GetCharacterPositionsAsync(textAnalysisInput);

            // Assert
            result.Should().NotBeNull();
            result.Count.Should().BeGreaterThan(0);
        }