From 524e50aad3adc3ea616c9cb3c97892fa46b6af5c Mon Sep 17 00:00:00 2001
From: Connor Kirkpatrick <ckp@amazon.com>
Date: Wed, 19 Jan 2022 11:53:40 +0000
Subject: [PATCH] Modernise witch.js (#43)

* Use const instead of var
* Incorporate feedback
---
 source/witch/witch.js | 166 ++++++++++++++++++++++--------------------
 1 file changed, 89 insertions(+), 77 deletions(-)

diff --git a/source/witch/witch.js b/source/witch/witch.js
index 5d1f12c..b4f163b 100644
--- a/source/witch/witch.js
+++ b/source/witch/witch.js
@@ -2,94 +2,106 @@ const aws = require("aws-sdk");
 const fs = require("fs");
 const path = require("path");
 const mime = require("mime-types");
+const https = require("https");
+const url = require("url");
 
 const s3 = new aws.S3();
 
 const SUCCESS = "SUCCESS";
 const FAILED = "FAILED";
 
-const BUCKET = process.env.BUCKET;
+const { BUCKET } = process.env;
 
-exports.staticHandler = function(event, context) {
-    if (event.RequestType !== "Create" && event.RequestType !== "Update") {
-        return respond(event, context, SUCCESS, {});
-    }
+exports.staticHandler = function (event, context) {
+  if (event.RequestType !== "Create" && event.RequestType !== "Update") {
+    return respond(event, context, SUCCESS, {});
+  }
+
+  Promise.all(
+    walkSync("./").map((file) => {
+      const fileType = mime.lookup(file) || "application/octet-stream";
 
-    Promise.all(walkSync("./").map(file => {
-        var fileType = mime.lookup(file) || "application/octet-stream";
-
-        console.log(`${file} -> ${fileType}`);
-
-        return s3.upload({
-            Body: fs.createReadStream(file),
-            Bucket: BUCKET,
-            ContentType: fileType,
-            Key: file,
-            ACL: "private",
-        }).promise();
-    })).then((msg) => {
-        respond(event, context, SUCCESS, {});
-    }).catch(err => {
-        respond(event, context, FAILED, {Message: err});
+      console.log(`${file} -> ${fileType}`);
+
+      return s3
+        .upload({
+          Body: fs.createReadStream(file),
+          Bucket: BUCKET,
+          ContentType: fileType,
+          Key: file,
+          ACL: "private",
+        })
+        .promise();
+    })
+  )
+    .then((msg) => {
+      respond(event, context, SUCCESS, {});
+    })
+    .catch((err) => {
+      respond(event, context, FAILED, { Message: err });
     });
 };
 
 // List all files in a directory in Node.js recursively in a synchronous fashion
-function walkSync(dir, filelist) {
-	var files = fs.readdirSync(dir);
-	filelist = filelist || [];
-
-	files.forEach(function(file) {
-		if (fs.statSync(path.join(dir, file)).isDirectory()) {
-			filelist = walkSync(path.join(dir, file), filelist);
-		} else {
-			filelist.push(path.join(dir, file));
-		}
-	});
-
-	return filelist;
-};
+function walkSync(dir, filelist = []) {
+  const files = fs.readdirSync(dir);
 
-function respond(event, context, responseStatus, responseData, physicalResourceId, noEcho) {
-    var responseBody = JSON.stringify({
-        Status: responseStatus,
-        Reason: "See the details in CloudWatch Log Stream: " + context.logStreamName,
-        PhysicalResourceId: physicalResourceId || context.logStreamName,
-        StackId: event.StackId,
-        RequestId: event.RequestId,
-        LogicalResourceId: event.LogicalResourceId,
-        NoEcho: noEcho || false,
-        Data: responseData
-    });
- 
-    console.log("Response body:\n", responseBody);
- 
-    var https = require("https");
-    var url = require("url");
- 
-    var parsedUrl = new url.URL(event.ResponseURL);
-    var options = {
-        hostname: parsedUrl.hostname,
-        port: 443,
-        path: parsedUrl.pathname + parsedUrl.search,
-        method: "PUT",
-        headers: {
-            "content-type": "",
-            "content-length": responseBody.length
-        }
-    };
- 
-    var request = https.request(options, function(response) {
-        console.log("Status code: " + response.statusCode);
-        console.log("Status message: " + response.statusMessage);
-        context.done();
-    });
- 
-    request.on("error", function(error) {
-        console.log("send(..) failed executing https.request(..): " + error);
-        context.done();
-    });
- 
-    request.write(responseBody);
-    request.end();
+  files.forEach(function (file) {
+    if (fs.statSync(path.join(dir, file)).isDirectory()) {
+      filelist = walkSync(path.join(dir, file), filelist);
+    } else {
+      filelist.push(path.join(dir, file));
+    }
+  });
+
+  return filelist;
+}
+
+function respond(
+  event,
+  context,
+  responseStatus,
+  responseData,
+  physicalResourceId,
+  noEcho
+) {
+  const responseBody = JSON.stringify({
+    Status: responseStatus,
+    Reason:
+      "See the details in CloudWatch Log Stream: " + context.logStreamName,
+    PhysicalResourceId: physicalResourceId || context.logStreamName,
+    StackId: event.StackId,
+    RequestId: event.RequestId,
+    LogicalResourceId: event.LogicalResourceId,
+    NoEcho: noEcho || false,
+    Data: responseData,
+  });
+
+  console.log("Response body:\n", responseBody);
+
+  const { pathname, hostname, search } = new url.URL(event.ResponseURL);
+  const options = {
+    hostname,
+    port: 443,
+    path: pathname + search,
+    method: "PUT",
+    headers: {
+      "content-type": "",
+      "content-length": responseBody.length,
+    },
+  };
+
+  const request = https.request(options, function (response) {
+    console.log("Status code: " + response.statusCode);
+    console.log("Status message: " + response.statusMessage);
+    context.done();
+  });
+
+  request.on("error", function (error) {
+    console.log("send(..) failed executing https.request(..): " + error);
+    context.done();
+  });
+
+  request.write(responseBody);
+  request.end();
 }