From a581a856339b1b31f388217265aa042532007cad Mon Sep 17 00:00:00 2001
From: Nelson Chan <3271800+chakflying@users.noreply.github.com>
Date: Mon, 20 May 2024 04:03:32 +0800
Subject: [PATCH] Feat: Use `UptimeCalculator` for PingChart (#4264)

Co-authored-by: Frank Elsinga <frank@elsinga.de>
---
 server/server.js                              |   2 +
 .../socket-handlers/chart-socket-handler.js   |  38 ++
 server/uptime-calculator.js                   |   6 +-
 src/components/PingChart.vue                  | 418 +++++++++++++++---
 src/mixins/datetime.js                        |  27 ++
 src/mixins/socket.js                          |  11 +
 6 files changed, 426 insertions(+), 76 deletions(-)
 create mode 100644 server/socket-handlers/chart-socket-handler.js

diff --git a/server/server.js b/server/server.js
index 28fb44267..38158c546 100644
--- a/server/server.js
+++ b/server/server.js
@@ -149,6 +149,7 @@ const apicache = require("./modules/apicache");
 const { resetChrome } = require("./monitor-types/real-browser-monitor-type");
 const { EmbeddedMariaDB } = require("./embedded-mariadb");
 const { SetupDatabase } = require("./setup-database");
+const { chartSocketHandler } = require("./socket-handlers/chart-socket-handler");
 
 app.use(express.json());
 
@@ -1528,6 +1529,7 @@ let needSetup = false;
         apiKeySocketHandler(socket);
         remoteBrowserSocketHandler(socket);
         generalSocketHandler(socket, server);
+        chartSocketHandler(socket);
 
         log.debug("server", "added all socket handlers");
 
diff --git a/server/socket-handlers/chart-socket-handler.js b/server/socket-handlers/chart-socket-handler.js
new file mode 100644
index 000000000..654db0e73
--- /dev/null
+++ b/server/socket-handlers/chart-socket-handler.js
@@ -0,0 +1,38 @@
+const { checkLogin } = require("../util-server");
+const { UptimeCalculator } = require("../uptime-calculator");
+const { log } = require("../../src/util");
+
+module.exports.chartSocketHandler = (socket) => {
+    socket.on("getMonitorChartData", async (monitorID, period, callback) => {
+        try {
+            checkLogin(socket);
+
+            log.debug("monitor", `Get Monitor Chart Data: ${monitorID} User ID: ${socket.userID}`);
+
+            if (period == null) {
+                throw new Error("Invalid period.");
+            }
+
+            let uptimeCalculator = await UptimeCalculator.getUptimeCalculator(monitorID);
+
+            let data;
+            if (period <= 24) {
+                data = uptimeCalculator.getDataArray(period * 60, "minute");
+            } else if (period <= 720) {
+                data = uptimeCalculator.getDataArray(period, "hour");
+            } else {
+                data = uptimeCalculator.getDataArray(period / 24, "day");
+            }
+
+            callback({
+                ok: true,
+                data,
+            });
+        } catch (e) {
+            callback({
+                ok: false,
+                msg: e.message,
+            });
+        }
+    });
+};
diff --git a/server/uptime-calculator.js b/server/uptime-calculator.js
index 3735a79a3..55059e960 100644
--- a/server/uptime-calculator.js
+++ b/server/uptime-calculator.js
@@ -290,7 +290,7 @@ class UptimeCalculator {
         dailyStatBean.pingMax = dailyData.maxPing;
         {
             // eslint-disable-next-line no-unused-vars
-            const { up, down, avgPing, minPing, maxPing, ...extras } = dailyData;
+            const { up, down, avgPing, minPing, maxPing, timestamp, ...extras } = dailyData;
             if (Object.keys(extras).length > 0) {
                 dailyStatBean.extras = JSON.stringify(extras);
             }
@@ -305,7 +305,7 @@ class UptimeCalculator {
         hourlyStatBean.pingMax = hourlyData.maxPing;
         {
             // eslint-disable-next-line no-unused-vars
-            const { up, down, avgPing, minPing, maxPing, ...extras } = hourlyData;
+            const { up, down, avgPing, minPing, maxPing, timestamp, ...extras } = hourlyData;
             if (Object.keys(extras).length > 0) {
                 hourlyStatBean.extras = JSON.stringify(extras);
             }
@@ -320,7 +320,7 @@ class UptimeCalculator {
         minutelyStatBean.pingMax = minutelyData.maxPing;
         {
             // eslint-disable-next-line no-unused-vars
-            const { up, down, avgPing, minPing, maxPing, ...extras } = minutelyData;
+            const { up, down, avgPing, minPing, maxPing, timestamp, ...extras } = minutelyData;
             if (Object.keys(extras).length > 0) {
                 minutelyStatBean.extras = JSON.stringify(extras);
             }
diff --git a/src/components/PingChart.vue b/src/components/PingChart.vue
index c550b4b4f..60b0d3c9c 100644
--- a/src/components/PingChart.vue
+++ b/src/components/PingChart.vue
@@ -1,16 +1,24 @@
 <template>
     <div>
         <div class="period-options">
-            <button type="button" class="btn btn-light dropdown-toggle btn-period-toggle" data-bs-toggle="dropdown" aria-expanded="false">
+            <button
+                type="button" class="btn btn-light dropdown-toggle btn-period-toggle" data-bs-toggle="dropdown"
+                aria-expanded="false"
+            >
                 {{ chartPeriodOptions[chartPeriodHrs] }}&nbsp;
             </button>
             <ul class="dropdown-menu dropdown-menu-end">
                 <li v-for="(item, key) in chartPeriodOptions" :key="key">
-                    <a class="dropdown-item" :class="{ active: chartPeriodHrs == key }" href="#" @click="chartPeriodHrs = key">{{ item }}</a>
+                    <button
+                        type="button" class="dropdown-item" :class="{ active: chartPeriodHrs == key }"
+                        @click="chartPeriodHrs = key"
+                    >
+                        {{ item }}
+                    </button>
                 </li>
             </ul>
         </div>
-        <div class="chart-wrapper" :class="{ loading : loading}">
+        <div class="chart-wrapper" :class="{ loading: loading }">
             <Line :data="chartData" :options="chartOptions" />
         </div>
     </div>
@@ -19,9 +27,8 @@
 <script lang="js">
 import { BarController, BarElement, Chart, Filler, LinearScale, LineController, LineElement, PointElement, TimeScale, Tooltip } from "chart.js";
 import "chartjs-adapter-dayjs-4";
-import dayjs from "dayjs";
 import { Line } from "vue-chartjs";
-import { DOWN, PENDING, MAINTENANCE, log } from "../util.ts";
+import { UP, DOWN, PENDING, MAINTENANCE } from "../util.ts";
 
 Chart.register(LineController, BarController, LineElement, PointElement, TimeScale, BarElement, LinearScale, Tooltip, Filler);
 
@@ -39,8 +46,9 @@ export default {
 
             loading: false,
 
-            // Configurable filtering on top of the returned data
-            chartPeriodHrs: 0,
+            // Time period for the chart to display, in hours
+            // Initial value is 0 as a workaround for triggering a data fetch on created()
+            chartPeriodHrs: "0",
 
             chartPeriodOptions: {
                 0: this.$t("recent"),
@@ -50,9 +58,8 @@ export default {
                 168: "1w",
             },
 
-            // A heartbeatList for 3h, 6h, 24h, 1w
-            // Uses the $root.heartbeatList when value is null
-            heartbeatList: null
+            chartRawData: null,
+            chartDataFetchInterval: null,
         };
     },
     computed: {
@@ -157,34 +164,197 @@ export default {
             };
         },
         chartData() {
+            if (this.chartPeriodHrs === "0") {
+                return this.getChartDatapointsFromHeartbeatList();
+            } else {
+                return this.getChartDatapointsFromStats();
+            }
+        },
+    },
+    watch: {
+        // Update chart data when the selected chart period changes
+        chartPeriodHrs: function (newPeriod) {
+            if (this.chartDataFetchInterval) {
+                clearInterval(this.chartDataFetchInterval);
+                this.chartDataFetchInterval = null;
+            }
+
+            // eslint-disable-next-line eqeqeq
+            if (newPeriod == "0") {
+                this.heartbeatList = null;
+                this.$root.storage().removeItem(`chart-period-${this.monitorId}`);
+            } else {
+                this.loading = true;
+
+                let period;
+                try {
+                    period = parseInt(newPeriod);
+                } catch (e) {
+                    // Invalid period
+                    period = 24;
+                }
+
+                this.$root.getMonitorChartData(this.monitorId, period, (res) => {
+                    if (!res.ok) {
+                        this.$root.toastError(res.msg);
+                    } else {
+                        this.chartRawData = res.data;
+                        this.$root.storage()[`chart-period-${this.monitorId}`] = newPeriod;
+                    }
+                    this.loading = false;
+                });
+
+                this.chartDataFetchInterval = setInterval(() => {
+                    this.$root.getMonitorChartData(this.monitorId, period, (res) => {
+                        if (res.ok) {
+                            this.chartRawData = res.data;
+                        }
+                    });
+                }, 5 * 60 * 1000);
+            }
+        }
+    },
+    created() {
+        // Load chart period from storage if saved
+        let period = this.$root.storage()[`chart-period-${this.monitorId}`];
+        if (period != null) {
+            // Has this ever been not a string?
+            if (typeof period !== "string") {
+                period = period.toString();
+            }
+            this.chartPeriodHrs = period;
+        } else {
+            this.chartPeriodHrs = "24";
+        }
+    },
+    beforeUnmount() {
+        if (this.chartDataFetchInterval) {
+            clearInterval(this.chartDataFetchInterval);
+        }
+    },
+    methods: {
+        // Get color of bar chart for this datapoint
+        getBarColorForDatapoint(datapoint) {
+            if (datapoint.maintenance != null) {
+                // Target is in maintenance
+                return "rgba(23,71,245,0.41)";
+            } else if (datapoint.down === 0) {
+                // Target is up, no need to display a bar
+                return "#000";
+            } else if (datapoint.up === 0) {
+                // Target is down
+                return "rgba(220, 53, 69, 0.41)";
+            } else {
+                // Show yellow for mixed status
+                return "rgba(245, 182, 23, 0.41)";
+            }
+        },
+        // push datapoint to chartData
+        pushDatapoint(datapoint, avgPingData, minPingData, maxPingData, downData, colorData) {
+            const x = this.$root.unixToDateTime(datapoint.timestamp);
+
+            // Show ping values if it was up in this period
+            avgPingData.push({
+                x,
+                y: datapoint.up > 0 && datapoint.avgPing > 0 ? datapoint.avgPing : null,
+            });
+            minPingData.push({
+                x,
+                y: datapoint.up > 0 && datapoint.avgPing > 0 ? datapoint.minPing : null,
+            });
+            maxPingData.push({
+                x,
+                y: datapoint.up > 0 && datapoint.avgPing > 0 ? datapoint.maxPing : null,
+            });
+            downData.push({
+                x,
+                y: datapoint.down + (datapoint.maintenance || 0),
+            });
+
+            colorData.push(this.getBarColorForDatapoint(datapoint));
+        },
+        // get the average of a set of datapoints
+        getAverage(datapoints) {
+            const totalUp = datapoints.reduce((total, current) => total + current.up, 0);
+            const totalDown = datapoints.reduce((total, current) => total + current.down, 0);
+            const totalMaintenance = datapoints.reduce((total, current) => total + (current.maintenance || 0), 0);
+            const totalPing = datapoints.reduce((total, current) => total + current.avgPing * current.up, 0);
+            const minPing = datapoints.reduce((min, current) => Math.min(min, current.minPing), Infinity);
+            const maxPing = datapoints.reduce((max, current) => Math.max(max, current.maxPing), 0);
+
+            // Find the middle timestamp to use
+            let midpoint = Math.floor(datapoints.length / 2);
+
+            return {
+                timestamp: datapoints[midpoint].timestamp,
+                up: totalUp,
+                down: totalDown,
+                maintenance: totalMaintenance > 0 ? totalMaintenance : undefined,
+                avgPing: totalUp > 0 ? totalPing / totalUp : 0,
+                minPing,
+                maxPing,
+            };
+        },
+        getChartDatapointsFromHeartbeatList() {
+            // Render chart using heartbeatList
+            let lastHeartbeatTime;
+            const monitorInterval = this.$root.monitorList[this.monitorId]?.interval;
             let pingData = [];  // Ping Data for Line Chart, y-axis contains ping time
             let downData = [];  // Down Data for Bar Chart, y-axis is 1 if target is down (red color), under maintenance (blue color) or pending (orange color), 0 if target is up
             let colorData = []; // Color Data for Bar Chart
 
-            let heartbeatList = this.heartbeatList ||
-             (this.monitorId in this.$root.heartbeatList && this.$root.heartbeatList[this.monitorId]) ||
-             [];
+            let heartbeatList = (this.monitorId in this.$root.heartbeatList && this.$root.heartbeatList[this.monitorId]) || [];
 
-            heartbeatList
-                .filter(
-                    // Filtering as data gets appended
-                    // not the most efficient, but works for now
-                    (beat) => dayjs.utc(beat.time).tz(this.$root.timezone).isAfter(
-                        dayjs().subtract(Math.max(this.chartPeriodHrs, 6), "hours")
-                    )
-                )
-                .map((beat) => {
-                    const x = this.$root.datetime(beat.time);
-                    pingData.push({
-                        x,
-                        y: beat.ping,
-                    });
-                    downData.push({
-                        x,
-                        y: (beat.status === DOWN || beat.status === MAINTENANCE || beat.status === PENDING) ? 1 : 0,
-                    });
-                    colorData.push((beat.status === MAINTENANCE) ? "rgba(23,71,245,0.41)" : ((beat.status === PENDING) ? "rgba(245,182,23,0.41)" : "#DC354568"));
+            for (const beat of heartbeatList) {
+                const beatTime = this.$root.toDayjs(beat.time);
+                const x = beatTime.format("YYYY-MM-DD HH:mm:ss");
+
+                // Insert empty datapoint to separate big gaps
+                if (lastHeartbeatTime && monitorInterval) {
+                    const diff = Math.abs(beatTime.diff(lastHeartbeatTime));
+                    if (diff > monitorInterval * 1000 * 10) {
+                        // Big gap detected
+                        const gapX = [
+                            lastHeartbeatTime.add(monitorInterval, "second").format("YYYY-MM-DD HH:mm:ss"),
+                            beatTime.subtract(monitorInterval, "second").format("YYYY-MM-DD HH:mm:ss")
+                        ];
+
+                        for (const x of gapX) {
+                            pingData.push({
+                                x,
+                                y: null,
+                            });
+                            downData.push({
+                                x,
+                                y: null,
+                            });
+                            colorData.push("#000");
+                        }
+
+                    }
+                }
+
+                pingData.push({
+                    x,
+                    y: beat.status === UP ? beat.ping : null,
                 });
+                downData.push({
+                    x,
+                    y: (beat.status === DOWN || beat.status === MAINTENANCE || beat.status === PENDING) ? 1 : 0,
+                });
+                switch (beat.status) {
+                    case MAINTENANCE:
+                        colorData.push("rgba(23 ,71, 245, 0.41)");
+                        break;
+                    case PENDING:
+                        colorData.push("rgba(245, 182, 23, 0.41)");
+                        break;
+                    default:
+                        colorData.push("rgba(220, 53, 69, 0.41)");
+                }
+
+                lastHeartbeatTime = beatTime;
+            }
 
             return {
                 datasets: [
@@ -214,54 +384,155 @@ export default {
                 ],
             };
         },
-    },
-    watch: {
-        // Update chart data when the selected chart period changes
-        chartPeriodHrs: function (newPeriod) {
+        getChartDatapointsFromStats() {
+            // Render chart using UptimeCalculator data
+            let lastHeartbeatTime;
+            const monitorInterval = this.$root.monitorList[this.monitorId]?.interval;
 
-            // eslint-disable-next-line eqeqeq
-            if (newPeriod == "0") {
-                this.heartbeatList = null;
-                this.$root.storage().removeItem(`chart-period-${this.monitorId}`);
-            } else {
-                this.loading = true;
+            let avgPingData = [];  // Ping Data for Line Chart, y-axis contains ping time
+            let minPingData = [];  // Ping Data for Line Chart, y-axis contains ping time
+            let maxPingData = [];  // Ping Data for Line Chart, y-axis contains ping time
+            let downData = [];  // Down Data for Bar Chart, y-axis is number of down datapoints in this period
+            let colorData = []; // Color Data for Bar Chart
 
-                this.$root.getMonitorBeats(this.monitorId, newPeriod, (res) => {
-                    if (!res.ok) {
-                        this.$root.toastError(res.msg);
+            const period = parseInt(this.chartPeriodHrs);
+            let aggregatePoints = period > 6 ? 12 : 4;
+
+            let aggregateBuffer = [];
+
+            if (this.chartRawData) {
+                for (const datapoint of this.chartRawData) {
+                    // Empty datapoints are ignored
+                    if (datapoint.up === 0 && datapoint.down === 0 && datapoint.maintenance === 0) {
+                        continue;
+                    }
+
+                    const beatTime = this.$root.unixToDayjs(datapoint.timestamp);
+
+                    // Insert empty datapoint to separate big gaps
+                    if (lastHeartbeatTime && monitorInterval) {
+                        const diff = Math.abs(beatTime.diff(lastHeartbeatTime));
+                        const oneSecond = 1000;
+                        const oneMinute = oneSecond * 60;
+                        const oneHour = oneMinute * 60;
+                        if ((period <= 24 && diff > Math.max(oneMinute * 10, monitorInterval * oneSecond * 10)) ||
+                            (period > 24 && diff > Math.max(oneHour * 10, monitorInterval * oneSecond * 10))) {
+                            // Big gap detected
+                            // Clear the aggregate buffer
+                            if (aggregateBuffer.length > 0) {
+                                const average = this.getAverage(aggregateBuffer);
+                                this.pushDatapoint(average, avgPingData, minPingData, maxPingData, downData, colorData);
+                                aggregateBuffer = [];
+                            }
+
+                            const gapX = [
+                                lastHeartbeatTime.subtract(monitorInterval, "second").format("YYYY-MM-DD HH:mm:ss"),
+                                this.$root.unixToDateTime(datapoint.timestamp + 60),
+                            ];
+
+                            for (const x of gapX) {
+                                avgPingData.push({
+                                    x,
+                                    y: null,
+                                });
+                                minPingData.push({
+                                    x,
+                                    y: null,
+                                });
+                                maxPingData.push({
+                                    x,
+                                    y: null,
+                                });
+                                downData.push({
+                                    x,
+                                    y: null,
+                                });
+                                colorData.push("#000");
+                            }
+
+                        }
+                    }
+
+                    if (datapoint.up > 0 && this.chartRawData.length > aggregatePoints * 2) {
+                        // Aggregate Up data using a sliding window
+                        aggregateBuffer.push(datapoint);
+
+                        if (aggregateBuffer.length === aggregatePoints) {
+                            const average = this.getAverage(aggregateBuffer);
+                            this.pushDatapoint(average, avgPingData, minPingData, maxPingData, downData, colorData);
+                            // Remove the first half of the buffer
+                            aggregateBuffer = aggregateBuffer.slice(Math.floor(aggregatePoints / 2));
+                        }
                     } else {
-                        this.heartbeatList = res.data;
-                        this.$root.storage()[`chart-period-${this.monitorId}`] = newPeriod;
-                    }
-                    this.loading = false;
-                });
-            }
-        }
-    },
-    created() {
-        // Setup Watcher on the root heartbeatList,
-        // And mirror latest change to this.heartbeatList
-        this.$watch(() => this.$root.heartbeatList[this.monitorId],
-            (heartbeatList) => {
+                        // datapoint is fully down or too few datapoints, no need to aggregate
+                        // Clear the aggregate buffer
+                        if (aggregateBuffer.length > 0) {
+                            const average = this.getAverage(aggregateBuffer);
+                            this.pushDatapoint(average, avgPingData, minPingData, maxPingData, downData, colorData);
+                            aggregateBuffer = [];
+                        }
 
-                log.debug("ping_chart", `this.chartPeriodHrs type ${typeof this.chartPeriodHrs}, value: ${this.chartPeriodHrs}`);
-
-                // eslint-disable-next-line eqeqeq
-                if (this.chartPeriodHrs != "0") {
-                    const newBeat = heartbeatList.at(-1);
-                    if (newBeat && dayjs.utc(newBeat.time) > dayjs.utc(this.heartbeatList.at(-1)?.time)) {
-                        this.heartbeatList.push(heartbeatList.at(-1));
+                        this.pushDatapoint(datapoint, avgPingData, minPingData, maxPingData, downData, colorData);
                     }
+
+                    lastHeartbeatTime = beatTime;
                 }
-            },
-            { deep: true }
-        );
+                // Clear the aggregate buffer if there are still datapoints
+                if (aggregateBuffer.length > 0) {
+                    const average = this.getAverage(aggregateBuffer);
+                    this.pushDatapoint(average, avgPingData, minPingData, maxPingData, downData, colorData);
+                    aggregateBuffer = [];
+                }
+            }
 
-        // Load chart period from storage if saved
-        let period = this.$root.storage()[`chart-period-${this.monitorId}`];
-        if (period != null) {
-            this.chartPeriodHrs = Math.min(period, 6);
-        }
+            return {
+                datasets: [
+                    {
+                        // average ping chart
+                        data: avgPingData,
+                        fill: "origin",
+                        tension: 0.2,
+                        borderColor: "#5CDD8B",
+                        backgroundColor: "#5CDD8B06",
+                        yAxisID: "y",
+                        label: "avg-ping",
+                    },
+                    {
+                        // minimum ping chart
+                        data: minPingData,
+                        fill: "origin",
+                        tension: 0.2,
+                        borderColor: "#3CBD6B38",
+                        backgroundColor: "#5CDD8B06",
+                        yAxisID: "y",
+                        label: "min-ping",
+                    },
+                    {
+                        // maximum ping chart
+                        data: maxPingData,
+                        fill: "origin",
+                        tension: 0.2,
+                        borderColor: "#7CBD6B38",
+                        backgroundColor: "#5CDD8B06",
+                        yAxisID: "y",
+                        label: "max-ping",
+                    },
+                    {
+                        // Bar Chart
+                        type: "bar",
+                        data: downData,
+                        borderColor: "#00000000",
+                        backgroundColor: colorData,
+                        yAxisID: "y1",
+                        barThickness: "flex",
+                        barPercentage: 1,
+                        categoryPercentage: 1,
+                        inflateAmount: 0.05,
+                        label: "status",
+                    },
+                ],
+            };
+        },
     }
 };
 </script>
@@ -296,6 +567,7 @@ export default {
 
             .dark & {
                 background: $dark-bg;
+                color: $dark-font-color;
             }
 
             .dark &:hover {
diff --git a/src/mixins/datetime.js b/src/mixins/datetime.js
index 1946d1902..ca2d8f018 100644
--- a/src/mixins/datetime.js
+++ b/src/mixins/datetime.js
@@ -41,6 +41,33 @@ export default {
             return this.datetimeFormat(value, "YYYY-MM-DD HH:mm:ss");
         },
 
+        /**
+         * Converts a Unix timestamp to a formatted date and time string.
+         * @param {number} value - The Unix timestamp to convert.
+         * @returns {string} The formatted date and time string.
+         */
+        unixToDateTime(value) {
+            return dayjs.unix(value).tz(this.timezone).format("YYYY-MM-DD HH:mm:ss");
+        },
+
+        /**
+         * Converts a Unix timestamp to a dayjs object.
+         * @param {number} value - The Unix timestamp to convert.
+         * @returns {dayjs.Dayjs} The dayjs object representing the given timestamp.
+         */
+        unixToDayjs(value) {
+            return dayjs.unix(value).tz(this.timezone);
+        },
+
+        /**
+         * Converts the given value to a dayjs object.
+         * @param {string} value - the value to be converted
+         * @returns {dayjs.Dayjs} a dayjs object in the timezone of this instance
+         */
+        toDayjs(value) {
+            return dayjs.utc(value).tz(this.timezone);
+        },
+
         /**
          * Get time for maintenance
          * @param {string | number | Date | dayjs.Dayjs} value Time to
diff --git a/src/mixins/socket.js b/src/mixins/socket.js
index a7a66fcab..150e39a25 100644
--- a/src/mixins/socket.js
+++ b/src/mixins/socket.js
@@ -673,6 +673,17 @@ export default {
         getMonitorBeats(monitorID, period, callback) {
             socket.emit("getMonitorBeats", monitorID, period, callback);
         },
+
+        /**
+         * Retrieves monitor chart data.
+         * @param {string} monitorID - The ID of the monitor.
+         * @param {number} period - The time period for the chart data, in hours.
+         * @param {socketCB} callback - The callback function to handle the chart data.
+         * @returns {void}
+         */
+        getMonitorChartData(monitorID, period, callback) {
+            socket.emit("getMonitorChartData", monitorID, period, callback);
+        }
     },
 
     computed: {