internal List Validate()

in Libraries/src/Amazon.Lambda.Annotations/SQS/SQSEventAttribute.cs [123:173]
46 lines of code
19 McCabe index (conditional complexity)

        internal List<string> Validate()
        {
            var validationErrors = new List<string>();

            if (IsBatchSizeSet && (BatchSize < 1 || BatchSize > 10000))
            {
                validationErrors.Add($"{nameof(SQSEventAttribute.BatchSize)} = {BatchSize}. It must be between 1 and 10000");
            }
            if (IsMaximumConcurrencySet && (MaximumConcurrency < 2 || MaximumConcurrency > 1000))
            {
                validationErrors.Add($"{nameof(SQSEventAttribute.MaximumConcurrency)} = {MaximumConcurrency}. It must be between 2 and 1000");
            }
            if (IsMaximumBatchingWindowInSecondsSet && (MaximumBatchingWindowInSeconds < 0 || MaximumBatchingWindowInSeconds > 300))
            {
                validationErrors.Add($"{nameof(SQSEventAttribute.MaximumBatchingWindowInSeconds)} = {MaximumBatchingWindowInSeconds}. It must be between 0 and 300");
            }
            if (IsBatchSizeSet && BatchSize > 10 && (!IsMaximumBatchingWindowInSecondsSet || MaximumBatchingWindowInSeconds < 1))
            {
                validationErrors.Add($"{nameof(SQSEventAttribute.MaximumBatchingWindowInSeconds)} is not set or set to a value less than 1. " +
                    $"It must be set to at least 1 when {nameof(SQSEventAttribute.BatchSize)} is greater than 10");
            }

            // The queue is FIFO if the queue ARN ends in ".fifo"
            var isFifo = !Queue.StartsWith("@") && Queue.EndsWith(".fifo");
            if (isFifo)
            {
                if (IsMaximumBatchingWindowInSecondsSet)
                {
                    validationErrors.Add($"{nameof(SQSEventAttribute.MaximumBatchingWindowInSeconds)} must not be set when the event source mapping is for a FIFO queue");
                }
                if (IsBatchSizeSet && BatchSize > 10)
                {
                    validationErrors.Add($"{nameof(SQSEventAttribute.BatchSize)} = {BatchSize}. It must be less than or equal to 10 when the event source mapping is for a FIFO queue");
                }
            }

            if (!Queue.StartsWith("@"))
            {
                var arnTokens = Queue.Split(new char[] { ':' }, 6);
                if (arnTokens.Length != 6) 
                {
                    validationErrors.Add($"{nameof(SQSEventAttribute.Queue)} = {Queue}. The SQS queue ARN is invalid. The ARN format is 'arn:<partition>:sqs:<region>:<account-id>:<queue-name>'");
                }
            }
            if (IsResourceNameSet && !_resourceNameRegex.IsMatch(ResourceName))
            {
                validationErrors.Add($"{nameof(SQSEventAttribute.ResourceName)} = {ResourceName}. It must only contain alphanumeric characters and must not be an empty string");
            }

            return validationErrors;
        }