support for updation of click count and visibility simultaneously

Author: lakshya-20

lambdas/url_access_patterns/lambda_for_updateURL/index.js

@@ -8,13 +8,42 @@ const AWS = require("aws-sdk");
 const dynamo = new AWS.DynamoDB.DocumentClient();
 
 function response(statusCode,error, message) {
-  return {
-    statusCode: statusCode,
-    body: message,
-    error:error
-  };
+    return {
+        statusCode: statusCode,
+        body: message,
+        error:error
+    };
+}
+/**
+* Checks if string is null or not based on custom conditions
+* @param {String} stringData The string to check null for
+* @return {Boolean} Tells whether [stringData] is null or not
+*/
+function nullCheck(stringData) {
+    return stringData!=="undefined" && stringData!=="null" && stringData!==""
+}
+/**
+* validate the string passed based on [nullCheck]
+* @param {String} queryString The string to be validated
+* @return {Boolean} Tells whether [queryString] is valid or not
+*/
+function isValidParam(queryString) {
+    if (queryString && nullCheck(queryString) ) {
+        return true
+    }
+        return false
+}
+/**
+* convert the passed string to boolean
+* @param {String} queryString The string to be converted
+* @return {Boolean} The converted string in boolean
+*/
+function getBoolean(queryString) {
+    if(queryString==="false"||queryString===false){
+        return false;
+    }
+    return true;
 }
-
 exports.handler = async (event) =>{
     const reqBody = event.body;
     var params = {
@@ -25,18 +54,22 @@ exports.handler = async (event) =>{
         },
         ReturnValues:"ALL_NEW"
     }
-    if(reqBody.visible!=undefined){    //request to change  visiblity of url
+    if(isValidParam(reqBody.visible) && isValidParam(reqBody.clicks_left)){  //request to change visibility and clicks_left
+        params.UpdateExpression="set visible = :val1, clicks_left = :val2"
+        params.ExpressionAttributeValues={":val1":getBoolean(reqBody.visible),":val2":parseInt(reqBody.clicks_left)}
+    }
+    else if(isValidParam(reqBody.visible)){    //request to change  visiblity of url
         params.UpdateExpression="set visible = :val"
-        params.ExpressionAttributeValues= {":val":reqBody.visible}
+        params.ExpressionAttributeValues= {":val":getBoolean(reqBody.visible)}
     }
-    else if(reqBody.clicks_left!=undefined){   //request to update clicks_left for url
+    else if(isValidParam(reqBody.clicks_left)){   //request to update clicks_left for url
         params.UpdateExpression="set clicks_left = :val"
-        params.ExpressionAttributeValues= {":val":reqBody.clicks_left}
+        params.ExpressionAttributeValues= {":val":parseInt(reqBody.clicks_left)}
     }
     try{
         const updated_url_data=  await dynamo.update(params).promise();
         return response(201,undefined,updated_url_data.Attributes);
     }catch(err){
         return response(500,"Internal Server Error",undefined);
     }
-}
+}