internal static List LoadSQSEventSourceConfig()

in Tools/LambdaTestTool-v2/src/Amazon.Lambda.TestTool/Processes/SQSEventSource/SQSEventSourceProcess.cs [118:239]
104 lines of code
23 McCabe index (conditional complexity)

    internal static List<SQSEventSourceConfig> LoadSQSEventSourceConfig(string sqsEventSourceConfigString)
    {
        if (File.Exists(sqsEventSourceConfigString))
        {
            sqsEventSourceConfigString = File.ReadAllText(sqsEventSourceConfigString);
        }

        sqsEventSourceConfigString = sqsEventSourceConfigString.Trim();

        List<SQSEventSourceConfig>? configs = null;

        var jsonOptions = new JsonSerializerOptions
        {
            PropertyNameCaseInsensitive = true
        };

        // Check to see if the config is in JSON array format.
        // The JSON format provides consistency with the API Gateway config style.
        if (sqsEventSourceConfigString.StartsWith('['))
        {
            try
            {
                configs = JsonSerializer.Deserialize<List<SQSEventSourceConfig>>(sqsEventSourceConfigString, jsonOptions);
                if (configs == null)
                {
                    throw new InvalidOperationException("Failed to parse SQS event source JSON config: " + sqsEventSourceConfigString);
                }
            }
            catch(JsonException e)
            {
                throw new InvalidOperationException("Failed to parse SQS event source JSON config: " + sqsEventSourceConfigString, e);
            }
        }
        // Config is a single object JSON document.
        // The JSON format provides consistency with the API Gateway config style.
        else if (sqsEventSourceConfigString.StartsWith('{'))
        {
            try
            {
                var config = JsonSerializer.Deserialize<SQSEventSourceConfig>(sqsEventSourceConfigString, jsonOptions);
                if (config == null)
                {
                    throw new InvalidOperationException("Failed to parse SQS event source JSON config: " + sqsEventSourceConfigString);
                }

                configs = new List<SQSEventSourceConfig> { config };
            }
            catch (JsonException e)
            {
                throw new InvalidOperationException("Failed to parse SQS event source JSON config: " + sqsEventSourceConfigString, e);
            }
        }
        // Config is a QueueUrl only. The current test tool instance will be assumed the Lambda runtime api and the
        // messages will be sent to the default function. Support this format allows for an
        // simple CLI experience of just providing a single value for the default scenario.
        else if (Uri.TryCreate(sqsEventSourceConfigString, UriKind.Absolute, out _))
        {
            configs = new List<SQSEventSourceConfig> { new SQSEventSourceConfig { QueueUrl = sqsEventSourceConfigString } };
        }
        // Config is in comma delimited key value pair format. This format allows setting all the parameters without having
        // to deal with escaping quotes like the JSON format.
        else
        {
            var config = new SQSEventSourceConfig();
            var tokens = sqsEventSourceConfigString.Split(',');
            foreach(var token in tokens)
            {
                if (string.IsNullOrWhiteSpace(token))
                    continue;

                var keyValuePair = token.Split('=');
                if (keyValuePair.Length != 2)
                {
                    throw new InvalidOperationException("Failed to parse SQS event source config. Format should be \"QueueUrl=<value>,FunctionName=<value>,...\"");
                }

                switch (keyValuePair[0].ToLower().Trim())
                {
                    case "batchsize":
                        if (!int.TryParse(keyValuePair[1].Trim(), out var batchSize))
                        {
                            throw new InvalidOperationException("Value for batch size is not a formatted integer");
                        }
                        config.BatchSize = batchSize;
                        break;
                    case "disablemessagedelete":
                        if (!bool.TryParse(keyValuePair[1].Trim(), out var disableMessageDelete))
                        {
                            throw new InvalidOperationException("Value for disable message delete is not a formatted boolean");
                        }
                        config.DisableMessageDelete = disableMessageDelete;
                        break;
                    case "functionname":
                        config.FunctionName = keyValuePair[1].Trim();
                        break;
                    case "lambdaruntimeapi":
                        config.LambdaRuntimeApi = keyValuePair[1].Trim();
                        break;
                    case "profile":
                        config.Profile = keyValuePair[1].Trim();
                        break;
                    case "queueurl":
                        config.QueueUrl = keyValuePair[1].Trim();
                        break;
                    case "region":
                        config.Region = keyValuePair[1].Trim();
                        break;
                    case "visibilitytimeout":
                        if (!int.TryParse(keyValuePair[1].Trim(), out var visibilityTimeout))
                        {
                            throw new InvalidOperationException("Value for visibility timeout is not a formatted integer");
                        }
                        config.VisibilityTimeout = visibilityTimeout;
                        break;
                }
            }

            configs = new List<SQSEventSourceConfig> { config };
        }

        return configs;
    }