timestamp_formatter.cpp

#include <iostream>
#include "timestamp_formatter.h"
#include "logger.h"
#include "events.h"

using namespace std;

/***
 *
 * Formats given string into string needed by YANG model
 *
 * @param timestamp parsed from syslog message
 * @return formatted timestamp that conforms to YANG model
 *
 */

static const unordered_map<string, string> g_monthDict {
    { "Jan", "01" },
    { "Feb", "02" },
    { "Mar", "03" },
    { "Apr", "04" },
    { "May", "05" },
    { "Jun", "06" },
    { "Jul", "07" },
    { "Aug", "08" },
    { "Sep", "09" },
    { "Oct", "10" },
    { "Nov", "11" },
    { "Dec", "12" }
};

string TimestampFormatter::getYear(string timestamp) {
    if(!m_storedTimestamp.empty()) {
        if(m_storedTimestamp.compare(timestamp) <= 0) {
            m_storedTimestamp = timestamp;
            return m_storedYear;
        }
    }
    // no last timestamp or year change
    // Use thread-safe localtime_r instead of localtime
    // On 64-bit systems, time_t is already 64-bit and Y2038-safe
    time_t currentTime = time(nullptr);
    struct tm tm_result;
    localtime_r(&currentTime, &tm_result);
    stringstream ss;
    auto currentYear = 1900 + tm_result.tm_year;
    ss << currentYear; // get current year
    string year = ss.str();
    m_storedTimestamp = timestamp;
    m_storedYear = year;
    return year;
}

string TimestampFormatter::changeTimestampFormat(vector<string> dateComponents) {
    if(dateComponents.size() < 3) {
        SWSS_LOG_ERROR("Timestamp formatter unable to format due to invalid input");
        return "";
    }
    string formattedTimestamp; // need to change format of Mmm dd hh:mm:ss.SSSSSS to YYYY-mm-ddThh:mm:ss.SSSSSSZ
    string month;
    auto it = g_monthDict.find(dateComponents[0]);
    if(it != g_monthDict.end()) {
        month = it->second;
    } else {
        SWSS_LOG_ERROR("Timestamp month was given in wrong format.\n");
        return "";
    }
    string day = dateComponents[1];
    if(day.size() == 1) { // convert 1 -> 01
       day.insert(day.begin(), '0');
    }
    string time = dateComponents[2];
    string currentTimestamp = month + day + time;
    string year = getYear(currentTimestamp);
    formattedTimestamp = year + "-" + month + "-" + day + "T" + time + "Z";
    return formattedTimestamp;
}