private async Task LogEventTransmissionSetup()

in src/AWS.Logger.Core/Core/AWSLoggerCore.cs [450:506]
49 lines of code
10 McCabe index (conditional complexity)

        private async Task<string> LogEventTransmissionSetup(CancellationToken token)
        {
            string serviceURL = GetServiceUrl();

            if (!_config.DisableLogGroupCreation)
            {
                var logGroupResponse = await _client.Value.DescribeLogGroupsAsync(new DescribeLogGroupsRequest
                {
                    LogGroupNamePrefix = _config.LogGroup
                }, token).ConfigureAwait(false);
                if (!IsSuccessStatusCode(logGroupResponse))
                {
                    LogLibraryServiceError(new System.Net.WebException($"Lookup LogGroup {_config.LogGroup} returned status: {logGroupResponse.HttpStatusCode}"), serviceURL);
                }

                if (logGroupResponse.LogGroups?.FirstOrDefault(x => string.Equals(x.LogGroupName, _config.LogGroup, StringComparison.Ordinal)) == null)
                {
                    var createGroupResponse = await _client.Value.CreateLogGroupAsync(new CreateLogGroupRequest { LogGroupName = _config.LogGroup }, token).ConfigureAwait(false);
                    if (!IsSuccessStatusCode(createGroupResponse))
                    {
                        LogLibraryServiceError(new System.Net.WebException($"Create LogGroup {_config.LogGroup} returned status: {createGroupResponse.HttpStatusCode}"), serviceURL);
                    }
                    else if (_config.NewLogGroupRetentionInDays.HasValue && _config.NewLogGroupRetentionInDays.Value > 0)
                    {
                        // If CreateLogGroup returns a success status code then this process is responsible for applying the retention policy.
                        // This prevents a case of multiple instances each trying to set the retention policy. 
                        PutRetentionPolicy(_config.NewLogGroupRetentionInDays.Value,_config.LogGroup, serviceURL, token);
                    }
                }
            }

            var currentStreamName = GenerateStreamName(_config);

            try
            {
                var streamResponse = await _client.Value.CreateLogStreamAsync(new CreateLogStreamRequest
                {
                    LogGroupName = _config.LogGroup,
                    LogStreamName = currentStreamName
                }, token).ConfigureAwait(false);
                if (!IsSuccessStatusCode(streamResponse))
                {
                    LogLibraryServiceError(new System.Net.WebException($"Create LogStream {currentStreamName} for LogGroup {_config.LogGroup} returned status: {streamResponse.HttpStatusCode}"), serviceURL);
                }
            }
            catch (ResourceAlreadyExistsException) when (!string.IsNullOrEmpty(_config.LogStreamName))
            {
            }
            catch (Exception ex)
            {
                LogLibraryServiceError(new Exception($"Create LogStream {currentStreamName} for LogGroup {_config.LogGroup} returned error: {ex.Message}"), serviceURL);
            }

            _repo = new LogEventBatch(_config.LogGroup, currentStreamName, Convert.ToInt32(_config.BatchPushInterval.TotalSeconds), _config.BatchSizeInBytes);

            return currentStreamName;
        }