How to use

findLast

function

in

LoDashStatic

function extractServiceSummary(serviceTrends) {
  const successCount = extractTrendPointsForSingleServiceOperation(serviceTrends, 'count.success-span');
  const failureCount = extractTrendPointsForSingleServiceOperation(serviceTrends, 'count.failure-span');
  const countPoints = toCountPoints(successCount, failureCount);
  const tp99DurationPoints = extractTrendPointsForSingleServiceOperation(serviceTrends, '*_99.duration');
  const latestTp99DurationDatapoint = _.findLast(tp99DurationPoints, point => point.value);

  return [{
    type: 'Incoming Requests',
    totalCount: dataPointsSum(countPoints),
    countPoints,
    avgSuccessPercent: toSuccessPercent(successCount, failureCount),
    successPercentPoints: toSuccessPercentPoints(successCount, failureCount),
    latestTp99Duration: latestTp99DurationDatapoint && latestTp99DurationDatapoint.value,
    tp99DurationPoints
  }];
}

function extractOperationSummary(values) {
  const groupedByOperationName = _.groupBy(values, val => val.operationName);
  return Object.keys(groupedByOperationName).map((operationName) => {
    const operationTrends = groupedByOperationName[operationName];

    const successPoints = extractTrendPointsForSingleServiceOperation(operationTrends, 'count.success-span');
    const failurePoints = extractTrendPointsForSingleServiceOperation(operationTrends, 'count.failure-span');
    const countPoints = toCountPoints(successPoints, failurePoints);
    const tp99DurationPoints = extractTrendPointsForSingleServiceOperation(operationTrends, '*_99.duration');
    const latestTp99DurationDatapoint = _.findLast(tp99DurationPoints, point => point.value);

    return {
      operationName,
      totalCount: dataPointsSum(countPoints),
      countPoints,
      avgSuccessPercent: toSuccessPercent(successPoints, failurePoints),
      successPercentPoints: toSuccessPercentPoints(successPoints, failurePoints),
      latestTp99Duration: latestTp99DurationDatapoint && latestTp99DurationDatapoint.value,
      tp99DurationPoints,
      failurePoints
    };
  });
}