Add example for excel to json with mapper from file and add docker support

examples/excel2json/index.js

@@ -0,0 +1,51 @@
+const XLSX = require("xlsx");
+const fs = require("fs");
+
+const NAME = process.env.APP_NAME || "excel2json";
+console.log("App Name =>", NAME);
+
+// load from env
+const INPUT_FILE = process.env.INPUT_FILE || "./data/people.xlsx";
+const OUTPUT_PATH = process.env.OUTPUT_PATH || "./data/outputs";
+const MAPPER_FILE = process.env.MAPPER_FILE || "./data/mapper.json";
+
+// get mapper in string
+const mapperString = fs.readFileSync(
+  MAPPER_FILE,
+  { encoding: "utf-8" },
+  (err) => {
+    if (err) throw err;
+    console.log("Load file suceed =>", MAPPER_FILE);
+  }
+);
+
+// convert mapper from string to json object
+const mapperJson = JSON.parse(mapperString);
+const columsData = mapperJson.data;
+
+// read workbook from excel file
+const wb = XLSX.readFile(INPUT_FILE);
+const xlData = XLSX.utils.sheet_to_json(wb.Sheets["Sheet1"]);
+
+// mapping the data from read excel file
+const data = xlData.map((row) => {
+  var _r = {};
+
+  columsData.map((col) => {
+    _r[col.label] = row[col.dataIndex];
+  });
+
+  return _r;
+});
+console.log("Data read from excel and mapped\n", data);
+
+// check directory and create it if not exist
+if (!fs.existsSync(OUTPUT_PATH)) {
+  fs.mkdirSync(OUTPUT_PATH);
+}
+
+// write to file
+fs.writeFile(`${OUTPUT_PATH}/people_${new Date().getTime()}.json`, JSON.stringify(data), (err) => {
+  if (err) throw err;
+  console.log("Write succeed!");
+});