private static string DeterminePayload()

in Tools/LambdaTestTool/src/Amazon.Lambda.TestTool/TestToolStartup.cs [267:347]
72 lines of code
16 McCabe index (conditional complexity)

        private static string DeterminePayload(LocalLambdaOptions localLambdaOptions, CommandLineOptions commandOptions, string lambdaAssemblyDirectory, string lambdaProjectDirectory, RunConfiguration runConfiguration)
        {
            var payload = commandOptions.Payload;

            bool payloadFileFound = false;
            if (!string.IsNullOrEmpty(payload))
            {
                if (Path.IsPathFullyQualified(payload) && File.Exists(payload))
                {
                    if (!shouldDisableLogs) runConfiguration.OutputWriter.WriteLine($"... Using payload with from the file {payload}");
                    payload = File.ReadAllText(payload);
                    payloadFileFound = true;
                }
                else
                {
                    // Look to see if the payload value is a file in
                    // * Directory with user Lambda assemblies.
                    // * Lambda project directory
                    // * Properties directory under the project directory. This is to make it easy to reconcile from the launchSettings.json file.
                    // * Is a saved sample request from the web interface
                    var possiblePaths = new[]
                    {
                        Path.Combine(lambdaAssemblyDirectory, payload),
                        Path.Combine(lambdaProjectDirectory, payload),
                        Path.Combine(lambdaProjectDirectory, "Properties", payload),
                        Path.Combine(localLambdaOptions.GetPreferenceDirectory(false), new SampleRequestManager(localLambdaOptions.GetPreferenceDirectory(false)).GetSaveRequestRelativePath(payload))
                    };
                    foreach (var possiblePath in possiblePaths)
                    {
                        if (File.Exists(possiblePath))
                        {
                            if (!shouldDisableLogs) runConfiguration.OutputWriter.WriteLine($"... Using payload with from the file {Path.GetFullPath(possiblePath)}");
                            payload = File.ReadAllText(possiblePath);
                            payloadFileFound = true;
                            break;
                        }
                    }
                }
            }

            if (!payloadFileFound)
            {
                if (!shouldDisableLogs)
                {
                    if (!string.IsNullOrEmpty(payload))
                    {
                        runConfiguration.OutputWriter.WriteLine($"... Using payload with the value {payload}");
                    }
                    else
                    {
                        runConfiguration.OutputWriter.WriteLine("... No payload configured. If a payload is required set the --payload switch to a file path or a JSON document.");
                    }
                }
            }

            try
            {
                var doc = JsonDocument.Parse(payload);
            }
            catch (JsonException)
            {
                try
                {
                    if (!payload.StartsWith("[") && !payload.StartsWith("{") && !payload.StartsWith("\""))
                    {
                        payload = "\"" + payload + "\"";
                        JsonDocument.Parse(payload);
                    }
                    else
                    {
                        throw;
                    }
                }
                catch (JsonException)
                {
                    throw new ArgumentException("Provided payload for Lambda function is not a valid JSON document.");
                }
            }

            return payload;
        }