Use js-xlsx library to allow to download Excel files from the displayed data

bower.json

@@ -2,14 +2,18 @@
   "name": "widget",
   "dependencies": {
     "moment": "2.22.2",
-    "echarts": "4.2.0-rc.2"
+    "echarts": "4.2.0-rc.2",
+    "js-xlsx": "0.15.2"
   },
   "exportsOverride": {
     "echarts": {
       "js": "dist/echarts.min.js"
     },
     "moment": {
       "js": "min/moment-with-locales.min.js"
+    },
+    "js-xlsx": {
+      "js": "dist/xlsx.mini.min.js"
     }
   }
 }

src/config.xml

@@ -1,8 +1,8 @@
 <?xml version='1.0' encoding='UTF-8'?>
-<widget xmlns="http://wirecloud.conwet.fi.upm.es/ns/macdescription/1" vendor="Ficodes" name="echarts" version="0.0.2">
+<widget xmlns="http://wirecloud.conwet.fi.upm.es/ns/macdescription/1" vendor="Ficodes" name="echarts" version="0.0.3a3">
 
     <details>
-        <title>ECharts widget</title>
+        <title>ECharts</title>
         <homepage>https://github.com/Wirecloud/echarts-widget</homepage>
         <authors>Carlos Blanco &lt;cblanco@ficodes.com&gt;</authors>
         <email>projects@ficodes.com</email>

src/css/style.css

@@ -4,11 +4,13 @@ html {
     width: 100%;
     height:100%;
 }
+
 body {
     font-family: 'Open Sans', sans-serif;
     font-size: 12px;
     color: #4A4A4A;
     background-color: #f9f9f9;
     width: 100%;
-    height:100%;
-}
+    height: 100%;
+    margin: 0px;
+}

src/index.html

@@ -12,8 +12,7 @@
         <script src="lib/js/moment-with-locales.min.js"></script>
 
         <!-- including eCharts lib -->
-        <!--<script src="lib/echarts_4.2.0-rc.2/echarts.min.js"></script>-->
-
+        <script src="lib/js/xlsx.mini.min.js"></script>
         <script src="lib/js/echarts.min.js"></script>
 
         <!-- style -->

src/js/ECharts.js

@@ -5,7 +5,7 @@
  */
 
 /* exported ECharts */
-/* globals echarts */
+/* globals echarts, XLSX */
 
 
 var ECharts = (function () {
@@ -73,7 +73,26 @@ var ECharts = (function () {
         echart.clear();
         echart.showLoading();
 
-        if (data && typeof data === "object") {
+        if (typeof data === "object") {
+            if (data.toolbox != null && data.toolbox.feature != null && data.toolbox.feature.saveAsExcel != null) {
+                data.toolbox.feature.mySaveAsExcel = data.toolbox.feature.saveAsExcel;
+                data.toolbox.feature.mySaveAsExcel.title = "Excel";
+                data.toolbox.feature.mySaveAsExcel.icon = "path://M432.45,595.444c0,2.177-4.661,6.82-11.305,6.82c-6.475,0-11.306-4.567-11.306-6.82s4.852-6.812,11.306-6.812C427.841,588.632,432.452,593.191,432.45,595.444L432.45,595.444z M421.155,589.876c-3.009,0-5.448,2.495-5.448,5.572s2.439,5.572,5.448,5.572c3.01,0,5.449-2.495,5.449-5.572C426.604,592.371,424.165,589.876,421.155,589.876L421.155,589.876z M421.146,591.891c-1.916,0-3.47,1.589-3.47,3.549c0,1.959,1.554,3.548,3.47,3.548s3.469-1.589,3.469-3.548C424.614,593.479,423.062,591.891,421.146,591.891L421.146,591.891zM421.146,591.891";
+                data.toolbox.feature.mySaveAsExcel.onclick = () => {
+                    let wb = XLSX.utils.book_new();
+                    let aoa = data.xAxis[0].data.map((x, index) => {
+                        let row = [x + 'Z'];
+                        data.series.forEach((serie) => {
+                            row.push(serie.data[index] * 100);
+                        });
+                        return row;
+                    });
+                    aoa.splice(0, 0, ["dateObserved", "fillLevel"]);
+                    XLSX.utils.book_append_sheet(wb, XLSX.utils.aoa_to_sheet(aoa), 'data')
+                    XLSX.writeFile(wb, 'data.xlsx');
+                };
+                delete data.toolbox.feature.saveAsExcel;
+            }
             try {
                 echart.setOption(data, true);
             } catch (e) {