lib/plugins/aws/logs/index.js/AwsLogs/getLogStreams
class AwsLogs:  getLogStreams() {
    const params = {
      logGroupName: this.options.logGroupName,
      descending: true,
      limit: 50,
      orderBy: 'LastEventTime',
    };

    return this.provider.request('CloudWatchLogs', 'describeLogStreams', params).then(reply => {
      if (!reply || reply.logStreams.length === 0) {
        throw new this.serverless.classes.Error('No existing streams for the function');
      }

      return _.chain(reply.logStreams)
        .filter(stream => _.includes(stream.logStreamName, '[$LATEST]'))
        .map('logStreamName')
        .value();
    });
  }