iamucil · November 15, 2021 11:47 · iamucil · Aug 4, 2021
diff --git a/generate_jwt_token_for_header_signature.js b/generate_jwt_token_for_header_signature.js
 /*
 https://jwt.io/introduction/
 In its compact form, JSON Web Tokens consist of three parts separated by dots (.), which are:

 Header
 Payload
 Signature

 Therefore, a JWT typically looks like the following.

 xxxxx.yyyyy.zzzzz

 Within Postman, this script has no dependencies.
 */
 function isNullOrEmpty(x) {
    return x === undefined || x === '' || x === null || typeof x === 'undefined';
 }

 function isNullOrEmptySpace(x) {
    return isNullOrEmpty(x) || typeof x.trim === 'function' &&
        isNullOrEmpty(x.trim().replace(/ /g, ''));
 }

 function isValidStringObject(s) {
    return isNullOrEmpty(s) === false &&
        Object.prototype.toString.call(s) === '[object String]';
 }

 /**
 * A function for logging that is browser-friendly and node.js-friendly.
 * @param  {string|object} text The text or object to be logged to the console.
 * @param  {boolean} error      If true, the text is logged as an error.
 * @return {void}
 */
 function log(text, error) {
    if (isNullOrEmptySpace(text)) {
        return;
    }

    // 2015.03.04 - if the parameter is not a string, then break down what it is
    if (isValidStringObject(text) === false) {
        text = JSON.stringify(text);
    }

    if (typeof window !== 'undefined' && window.console) {

        if (error && window.console.error) {
            window.console.error(text);
        } else if (window.console.log) {
            window.console.log(text);
        }
    } else if (typeof document !== 'undefined' && document.console) {

        if (error && document.console.error) {
            document.console.error(text);
        } else if (document.console.log) {
            document.console.log(text);
        }
    } else if (console) {
        if (error && console.error) {
            console.error(text);
        } else if (console.log) {
            console.log(text);
        }
    }
 }

 function cleanBase64(input) {
    if (isNullOrEmptySpace(input) === true) {
        return '';
    }

    return input.replace(/=+$/, '').replace(/\+/g, '-').replace(/\//g, '_');
 }

 /**
 * Base64-encoded the given string. For the header and payload, make
 * sure that JSON.stringify() was called first.
 * @param  {string} input JSON-encoded string to encode via base64.
 * @return {string} A base64-encoded JSON string with certain characters replaced for compatibility.
 */
 function toBase64UrlEncoded(input) {
    // 1. Convert the variable to base64
    // btoa - binary data to base64-encoded ascii
    // https://www.npmjs.com/package/btoa
    var converted = btoa(input);
    // 2. Clean the converted input of invalid characters
    return cleanBase64(converted);
 }

 /**
 * Creates the signature of the JWT.
 * @param  {object} encodedHeader  Base64-encoded header string.
 * @param  {object} encodedPayload Base64-encoded payload string.
 * @param  {string} secret  The API secret from Zoom.
 * @return {string} The JWT signature.
 */
 function createSignature(encodedHeader, encodedPayload, secret) {
    if (isNullOrEmptySpace(encodedHeader) === true ||
        isNullOrEmptySpace(encodedPayload) === true ||
        isNullOrEmptySpace(secret) === true) {
        log('signature could not be created due to missing JWT part')
        return '';
    }

    var hash = CryptoJS.HmacSHA256((encodedHeader + '.' + encodedPayload), secret);
    var hashBase64Encoded = CryptoJS.enc.Base64.stringify(hash);
    var hashCleaned = cleanBase64(hashBase64Encoded);

    return hashCleaned;
 }

 /**
 * Creates a JWT from a header object, payload object, and an API secret.
 * Was created with Zoom (zoom.us) in mind.
 * @param  {object} header
 * @param  {object} payload
 * @param  {string} secret  The API secret from Zoom.
 * @return {string} The JWT token.
 */
 function generateJWT(header, payload, secret) {

    const originalHeader = JSON.stringify(header);
    const originalPayload = JSON.stringify(payload);

    // 1. Base64 encode the header
    var encodedHeader = toBase64UrlEncoded(originalHeader);

    // 2. Base64 encode the payload
    var encodedPayload = toBase64UrlEncoded(originalPayload);
    const originalSecret = secret.trim();

    // 3. Use the encoded header and payload along with the secret to
    // create the signature
    var signature = createSignature(
        encodedHeader,
        encodedPayload,
        originalSecret
    );

    // 4. Return them combined.
    return encodedHeader + '.' + encodedPayload + '.' + signature;
 }

 var requestMethod = pm.request.method.toUpperCase();

 const header = {
    'alg': 'HS256',
    'typ': 'JWT',
    'method': requestMethod
 };

 var now = (new Date()).getTime();
 var exp = now + 5000;
 const apiKey = pm.environment.get('MERCHANT_KEY');
 const apiSecret = pm.environment.get('MERCHANT_SECRET');
 if (isNullOrEmpty(apiKey)) {
    throw new Error("Entity values do not match");
 }

 if (isNullOrEmpty(apiSecret)) {
    throw new Error("Entity values do not match");
 }
 const secretToken = apiKey + ':' + apiSecret;
 log("secret >> " + secretToken);
 /**
 * Inside the payload, the keys of the object are claims.
 * Registered claims is from request body (payload) which is json request
 */
 let requestData = pm.request.body;
 if (requestData == '') {
    var payload = {
        // retrieves the Zoom API key using the environment variable for this collection
        'iss': apiKey.trim(),
        'exp': exp,
        'iat': now
    };
 } else {
    var payload = JSON.parse(pm.request.body);
 }
 /**
 * Generates the JWT
 */

 var jwt = generateJWT(header, payload, secretToken);

 // retrieves the 'apiToken' variable from the collection
 pm.variables.set('apiToken', jwt);
 log('jwt: ' + jwt);
	/*
	https://jwt.io/introduction/
	In its compact form, JSON Web Tokens consist of three parts separated by dots (.), which are:

	Header
	Payload
	Signature

	Therefore, a JWT typically looks like the following.

	xxxxx.yyyyy.zzzzz

	Within Postman, this script has no dependencies.
	*/
	function isNullOrEmpty(x) {
	return x === undefined \|\| x === '' \|\| x === null \|\| typeof x === 'undefined';
	}

	function isNullOrEmptySpace(x) {
	return isNullOrEmpty(x) \|\| typeof x.trim === 'function' &&
	isNullOrEmpty(x.trim().replace(/ /g, ''));
	}

	function isValidStringObject(s) {
	return isNullOrEmpty(s) === false &&
	Object.prototype.toString.call(s) === '[object String]';
	}

	/**
	* A function for logging that is browser-friendly and node.js-friendly.
	* @param {string\|object} text The text or object to be logged to the console.
	* @param {boolean} error If true, the text is logged as an error.
	* @return {void}
	*/
	function log(text, error) {
	if (isNullOrEmptySpace(text)) {
	return;
	}

	// 2015.03.04 - if the parameter is not a string, then break down what it is
	if (isValidStringObject(text) === false) {
	text = JSON.stringify(text);
	}

	if (typeof window !== 'undefined' && window.console) {

	if (error && window.console.error) {
	window.console.error(text);
	} else if (window.console.log) {
	window.console.log(text);
	}
	} else if (typeof document !== 'undefined' && document.console) {

	if (error && document.console.error) {
	document.console.error(text);
	} else if (document.console.log) {
	document.console.log(text);
	}
	} else if (console) {
	if (error && console.error) {
	console.error(text);
	} else if (console.log) {
	console.log(text);
	}
	}
	}

	function cleanBase64(input) {
	if (isNullOrEmptySpace(input) === true) {
	return '';
	}

	return input.replace(/=+$/, '').replace(/\+/g, '-').replace(/\//g, '_');
	}

	/**
	* Base64-encoded the given string. For the header and payload, make
	* sure that JSON.stringify() was called first.
	* @param {string} input JSON-encoded string to encode via base64.
	* @return {string} A base64-encoded JSON string with certain characters replaced for compatibility.
	*/
	function toBase64UrlEncoded(input) {
	// 1. Convert the variable to base64
	// btoa - binary data to base64-encoded ascii
	// https://www.npmjs.com/package/btoa
	var converted = btoa(input);
	// 2. Clean the converted input of invalid characters
	return cleanBase64(converted);
	}

	/**
	* Creates the signature of the JWT.
	* @param {object} encodedHeader Base64-encoded header string.
	* @param {object} encodedPayload Base64-encoded payload string.
	* @param {string} secret The API secret from Zoom.
	* @return {string} The JWT signature.
	*/
	function createSignature(encodedHeader, encodedPayload, secret) {
	if (isNullOrEmptySpace(encodedHeader) === true \|\|
	isNullOrEmptySpace(encodedPayload) === true \|\|
	isNullOrEmptySpace(secret) === true) {
	log('signature could not be created due to missing JWT part')
	return '';
	}

	var hash = CryptoJS.HmacSHA256((encodedHeader + '.' + encodedPayload), secret);
	var hashBase64Encoded = CryptoJS.enc.Base64.stringify(hash);
	var hashCleaned = cleanBase64(hashBase64Encoded);

	return hashCleaned;
	}

	/**
	* Creates a JWT from a header object, payload object, and an API secret.
	* Was created with Zoom (zoom.us) in mind.
	* @param {object} header
	* @param {object} payload
	* @param {string} secret The API secret from Zoom.
	* @return {string} The JWT token.
	*/
	function generateJWT(header, payload, secret) {

	const originalHeader = JSON.stringify(header);
	const originalPayload = JSON.stringify(payload);

	// 1. Base64 encode the header
	var encodedHeader = toBase64UrlEncoded(originalHeader);

	// 2. Base64 encode the payload
	var encodedPayload = toBase64UrlEncoded(originalPayload);
	const originalSecret = secret.trim();

	// 3. Use the encoded header and payload along with the secret to
	// create the signature
	var signature = createSignature(
	encodedHeader,
	encodedPayload,
	originalSecret
	);

	// 4. Return them combined.
	return encodedHeader + '.' + encodedPayload + '.' + signature;
	}

	var requestMethod = pm.request.method.toUpperCase();

	const header = {
	'alg': 'HS256',
	'typ': 'JWT',
	'method': requestMethod
	};

	var now = (new Date()).getTime();
	var exp = now + 5000;
	const apiKey = pm.environment.get('MERCHANT_KEY');
	const apiSecret = pm.environment.get('MERCHANT_SECRET');
	if (isNullOrEmpty(apiKey)) {
	throw new Error("Entity values do not match");
	}

	if (isNullOrEmpty(apiSecret)) {
	throw new Error("Entity values do not match");
	}
	const secretToken = apiKey + ':' + apiSecret;
	log("secret >> " + secretToken);
	/**
	* Inside the payload, the keys of the object are claims.
	* Registered claims is from request body (payload) which is json request
	*/
	let requestData = pm.request.body;
	if (requestData == '') {
	var payload = {
	// retrieves the Zoom API key using the environment variable for this collection
	'iss': apiKey.trim(),
	'exp': exp,
	'iat': now
	};
	} else {
	var payload = JSON.parse(pm.request.body);
	}
	/**
	* Generates the JWT
	*/

	var jwt = generateJWT(header, payload, secretToken);

	// retrieves the 'apiToken' variable from the collection
	pm.variables.set('apiToken', jwt);
	log('jwt: ' + jwt);