fixed utilization of updated version of tar, added unit tests

dynamodb/config.json

@@ -1,10 +1,10 @@
 {
-    "setup": {
-        "download_url": "http://s3-us-west-2.amazonaws.com/dynamodb-local/dynamodb_local_latest.tar.gz",
-        "install_path": "./bin",
-        "jar": "DynamoDBLocal.jar"
-    },
-    "start": {
-        "port": 8000
-    }
+  "setup": {
+    "download_url": "http://s3-us-west-2.amazonaws.com/dynamodb-local/dynamodb_local_latest.tar.gz",
+    "install_path": "bin",
+    "jar": "DynamoDBLocal.jar"
+  },
+  "start": {
+    "port": 8000
+  }
 }

dynamodb/installer.js

@@ -1,62 +1,75 @@
-'use strict';
+"use strict";
 
-var tar = require('tar'),
-    zlib = require('zlib'),
-    path = require('path'),
-    http = require('http'),
-    fs = require('fs'),
-    ProgressBar = require('progress'),
-    utils = require('./utils');
+var tar = require("tar"),
+  zlib = require("zlib"),
+  path = require("path"),
+  http = require("http"),
+  fs = require("fs"),
+  ProgressBar = require("progress"),
+  utils = require("./utils");
 
-var download = function (downloadUrl, installPath, callback) {
-    console.log("Started downloading Dynamodb-local. Process may take few minutes.");
-    http.get(downloadUrl, function (response) {
-            var len = parseInt(response.headers['content-length'], 10),
-            bar = new ProgressBar('Downloading dynamodb-local [:bar] :percent :etas', {
-                complete: '=',
-                incomplete: ' ',
-                width: 40,
-                total: len
-            });
+var download = function(downloadUrl, installPath, callback) {
+  console.log(
+    `Started downloading dynamodb-local from ${downloadUrl} into ${installPath}. Process may take few minutes.`
+  );
+  http
+    .get(downloadUrl, function(response) {
+      var len = parseInt(response.headers["content-length"], 10),
+        bar = new ProgressBar(
+          "Downloading dynamodb-local [:bar] :percent :etas",
+          {
+            complete: "=",
+            incomplete: " ",
+            width: 40,
+            total: len
+          }
+        );
 
-            if (200 != response.statusCode) {
-                throw new Error('Error getting DynamoDb local latest tar.gz location ' + response.headers.location + ': ' + response.statusCode);
-            }
+      if (200 != response.statusCode) {
+        throw new Error(
+          "Error getting DynamoDb local latest tar.gz location " +
+            response.headers.location +
+            ": " +
+            response.statusCode
+        );
+      }
 
-            response
-                .pipe(zlib.Unzip())
-                .pipe(tar.Extract({
-                    path: installPath
-                }))
-                .on('data', function (chunk) {
-                    bar.tick(chunk.length);
-                })
-                .on('end', function () {
-                    callback("\n Installation complete!");
-                })
-                .on('error', function (err) {
-                    throw new Error("Error in downloading Dynamodb local " + err);
-                });
-            })
-        .on('error', function (err) {
-            throw new Error("Error in downloading Dynamodb local " + err);
+      response
+        .pipe(zlib.Unzip())
+        .pipe(
+          tar.x({
+            C: installPath
+          })
+        )
+        .on("data", function(chunk) {
+          bar.tick(chunk.length);
+        })
+        .on("end", function() {
+          callback("\n Installation complete!");
+        })
+        .on("error", function(err) {
+          throw new Error("Error in downloading Dynamodb local " + err);
         });
+    })
+    .on("error", function(err) {
+      throw new Error("Error in downloading Dynamodb local " + err);
+    });
 };
 
-var install = function (config, callback) {
-    var install_path = utils.absPath(config.setup.install_path),
-        jar = config.setup.jar,
-        download_url = config.setup.download_url;
+var install = function(config, callback) {
+  var install_path = utils.absPath(config.setup.install_path),
+    jar = config.setup.jar,
+    download_url = config.setup.download_url;
 
-    try {
-        if (fs.existsSync(path.join(install_path, jar))) {
-            callback("Dynamodb is already installed on path!");
-        } else {
-            utils.createDir(config.setup.install_path);
-            download(download_url, install_path, callback);
-        }
-    } catch (err) {
-        throw new Error("Error configuring or installing Dynamodb local " + err);
+  try {
+    if (fs.existsSync(path.join(install_path, jar))) {
+      callback("Dynamodb is already installed on path!");
+    } else {
+      utils.createDir(config.setup.install_path);
+      download(download_url, install_path, callback);
     }
+  } catch (err) {
+    throw new Error("Error configuring or installing Dynamodb local " + err);
+  }
 };
 module.exports.install = install;