Develop Reference

Querying Azure Table Storage with Pure Javascript

I am trying to query Azure Table storage without using NodeJS. If I run the query on the whole table (sales) I get all the results fine, but when I want to filter on Partition Key and RowKey I get the error "Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature"
Here is my code
var storageAccount = 'xxxxxxxxx';
var accountKey = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
var date = new Date();
var UTCString = date.toUTCString();
var dataToEncode = UTCString + "\n" + "/" + storageAccount + "/sales";
var hash = CryptoJS.HmacSHA256(dataToEncode, CryptoJS.enc.Base64.parse(accountKey));
var strSignature = CryptoJS.enc.Base64.stringify(hash);
var auth = "SharedKeyLite " + storageAccount + ":" + strSignature;
var tableName = 'sales';
var pk ="CAR1748"
var rk = "1";
var queryString = encodeURIComponent(tableName + "(PartitionKey='" + pk + "',RowKey='" + rk + "')");
var path = "https://" + storageAccount + ".table.core.windows.net/" + queryString ;
var header = { "Accept" : "application/json;odata=nometadata", "x-ms-date" : UTCString , "Authorization" : auth , "x-ms-version": "2021-06-08", "DataServiceVersion": "3.0;NetFx","MaxDataServiceVersion": "3.0;NetFx" };
try {
var response = https.get({
url: path,
headers: header
});
context.response.write(response.code);
} catch (e) {
//context.response.write(response.code);
context.response.write(response.body);
return true;
}

Based on the documentation provided here, you would need to include the query string in your data to encode.
So your code would be something like:
var storageAccount = 'xxxxxxxxx';
var accountKey = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
var tableName = 'sales';
var pk ="CAR1748"
var rk = "1";
var date = new Date();
var UTCString = date.toUTCString();
var queryString = encodeURIComponent(tableName + "(PartitionKey='" + pk + "',RowKey='" + rk + "')");
var dataToEncode = UTCString + "\n" + "/" + storageAccount + "/" + queryString;
var hash = CryptoJS.HmacSHA256(dataToEncode, CryptoJS.enc.Base64.parse(accountKey));
var strSignature = CryptoJS.enc.Base64.stringify(hash);
var auth = "SharedKeyLite " + storageAccount + ":" + strSignature;
var path = "https://" + storageAccount + ".table.core.windows.net/" + queryString ;
var header = { "Accept" : "application/json;odata=nometadata", "x-ms-date" : UTCString , "Authorization" : auth , "x-ms-version": "2021-06-08", "DataServiceVersion": "3.0;NetFx","MaxDataServiceVersion": "3.0;NetFx" };
try {
var response = https.get({
url: path,
headers: header
});
context.response.write(response.code);
} catch (e) {
//context.response.write(response.code);
context.response.write(response.body);
return true;
}

Sending message to Telegram from Google Sheet via Google Scripts

I'm trying to send a telegram message to myself, every morning, with a different quote that I have listed in a Google Sheet. I wrote some code that adds messages to the list, but I can't seem to generate a random row from the list to send daily.
var token = "TOKEN";
var telegramAPI = "https://api.telegram.org/bot" + token;
var webAppAPI = "https://script.google.com/macros/s/GOOGLE_WEB_APP_ADDRESS";
var ssId = "SPREADSHEET_ID";
function getMe() {
var url = telegramAPI + "/getMe";
var response = UrlFetchApp.fetch(url);
Logger.log(response.getContentText());
}
function setWebhook() {
var url = telegramAPI + "/setWebhook?url=" + webAppAPI;
var response = UrlFetchApp.fetch(url);
Logger.log(response.getContentText());
}
function sendText(id,text) {
var url = telegramAPI + "/sendMessage?chat_id=" + id + "&text=" + text;
var response = UrlFetchApp.fetch(url);
Logger.log(response.getContentText());
}
function doGet(e) {
return HtmlService.createHtmlOutput("Test Data" + JSON.stringify(e,null,4));
}
function doPost(e) {
Logger.log(e);
var data = JSON.parse(e.postData.contents);
var text = data.message.text;
var what = data.message.text.split("-")[0]
var who = data.message.text.split("-")[1]
var id = data.message.chat.id;
var name = data.message.chat.first_name;
var response = "Hi " + name + ", this quote has been added to your database: " + text;
sendText(id,response);
SpreadsheetApp.openById(ssId).getSheets()[1].appendRow([new Date(),id,name,text,response,what,who]);
All of this works fine. I added a query that pulls them over to my Quote sheet from my Telegram Feed sheet, that I'll put here to help someone:
=IFERROR(QUERY('Telegram Feed'!$G$1:$G$98,"",-1),"Error")
Now that I'm pulling in quotes, I want to generate a random one from the list and schedule it to send to myself on a daily basis. I've included what I've tried below, but I can't seem to figure out what I'm doing wrong.
The randomizer is partially working, but seems to be grabbing all of the content, which I need to refactor to say something along the lines of:
message = f"{quote} + ' - ' + {author}"
Randomizer:
function randomizer() {
var ssa = SpreadsheetApp.openById(ssId);
var ss = ssa.getSheetByName('Quotes');
var range = ss.getRange(1,1,ss.getLastRow(), 2);
var data = range.getValues();
for(var i = 0; i < data.length; i++)
{
var j = Math.floor(Math.random()*(data[i].length));
var element = data[i][j];
ss.getRange(i+1, 6).setValue(element);
Logger.log(element);
}
}
Up until this point, it mostly works (even though I need to figure out how to fix the randomizer function as mentioned above. It's when I try to send a random message from the script to Telegram that I run into problems.
function sendQuote(what,who) {
var data = randomizer();
var dataJSON = JSON.parse(data.postData.contents);
var url = telegramAPI + "/sendMessage?chat_id=" + 'CHAT_ID_NUM' + "&text=" + what + " - " who;
}
I'm getting nothing back. Anyone know what I'm doing wrong?
EDIT:
I followed the suggestions from Дмитро-Булах & carlesgg97, and I refactored a bunch of my randomize code to give me a quote and author. For some reason, I'm now getting the error "TypeError: Cannot read property "postData" from undefined.: from the line that reads var dataJSON = JSON.parse(data.postData.contents);
Does anyone know why this is happening?
I'll close the issue within 24hrs regardless. Thanks for the help everybody!
function sendQuote(quote,author) {
var data = randomize();
var dataJSON = JSON.parse(data.postData.contents);
var encodedText = encodeURIComponent(quote + " - " + author);
var url = telegramAPI + "/sendMessage?chat_id=" + 'CHAT_ID' + "&text=" + encodedText;
UrlFetchApp.fetch(url);
}
function randomize() {
var sss = SpreadsheetApp.openById(ssId);
var ss = sss.getSheetByName('Quotes');
var length = ss.getLastRow();
var overshoot = 97 //monitor for changes as list size increases
var true_length = length-overshoot;
var line = (Math.random() * ((true_length - 2) + 1)) + 2;
var quote_cell = ss.getRange(line,2);
var quote = quote_cell.getValue();
var author_cell = ss.getRange(line,1);
var author = author_cell.getValue();
Logger.log(quote + " - " + author);
}

Seems like you may be having two different problems:
You are not encoding the text as URL-safe. To safely append data (in this case the text URL Query string parameter) to your URL, you should use encodeURIComponent().
You don't seem to actually be sending the request. Did you miss the UrlFetchApp.fetch() call?
See below an example that fixes both issues:
function sendQuote(what,who) {
var data = randomizer();
var dataJSON = JSON.parse(data.postData.contents);
var encodedText = encodeURIComponent(what + " - " + who);
var url = telegramAPI + "/sendMessage?chat_id=" + 'CHAT_ID_NUM' + "&text=" + encodedText;
UrlFetchApp.fetch(url);
}

Zapier Code (JS) + Twitter API - POST statuses/update (in_reply_to_status_id)

What I'm trying to achieve is a Zapier Code (JS) action to preform a Twitter reply to a given status ID with a given text .
I'm already using the functioning Zapier (JS) Code action offered by #KayCee which preform a POST favorites/create and would like to modify it so it would preform a reply action to any given status_id using the POST statuses/update (in_reply_to_status_id) as instructed by Twitter API.
Here is #KayCee's code with the modifications I made to preform a reply:
// This code requires that you set the ID of the tweet that you want to reply to as an input variable called "reply_to_id" and the text you wish to reply as an input variable called "status_text". Learn more at https://zapier.com/help/code/#data-variables
// INSTUCTIONS FOR SETTING THESE REQUIRED VARIABLES: After you create a new app at https://apps.twitter.com/, click on the name of the app to open it. Then, select the "Keys and Access Tokens" tab.
var twitterApplicationConsumerKey = 'CONSUMERKEY';
var twitterApplicationConsumerSecret = 'CONSUMERSECRET';
var twitterApplicationAccessToken = 'ACCESSTOKEN';
var twitterApplicationAccessTokenSecret = 'ACCESSTOKENSECRET';
// That's it. No need to edit anything below.
function b64_hmac_sha1(k,d,_p,_z){
if(!_p){_p='=';}if(!_z){_z=8;}function _f(t,b,c,d){if(t<20){return(b&c)|((~b)&d);}if(t<40){return b^c^d;}if(t<60){return(b&c)|(b&d)|(c&d);}return b^c^d;}function _k(t){return(t<20)?1518500249:(t<40)?1859775393:(t<60)?-1894007588:-899497514;}function _s(x,y){var l=(x&0xFFFF)+(y&0xFFFF),m=(x>>16)+(y>>16)+(l>>16);return(m<<16)|(l&0xFFFF);}function _r(n,c){return(n<<c)|(n>>>(32-c));}function _c(x,l){x[l>>5]|=0x80<<(24-l%32);x[((l+64>>9)<<4)+15]=l;var w=[80],a=1732584193,b=-271733879,c=-1732584194,d=271733878,e=-1009589776;for(var i=0;i<x.length;i+=16){var o=a,p=b,q=c,r=d,s=e;for(var j=0;j<80;j++){if(j<16){w[j]=x[i+j];}else{w[j]=_r(w[j-3]^w[j-8]^w[j-14]^w[j-16],1);}var t=_s(_s(_r(a,5),_f(j,b,c,d)),_s(_s(e,w[j]),_k(j)));e=d;d=c;c=_r(b,30);b=a;a=t;}a=_s(a,o);b=_s(b,p);c=_s(c,q);d=_s(d,r);e=_s(e,s);}return[a,b,c,d,e];}function _b(s){var b=[],m=(1<<_z)-1;for(var i=0;i<s.length*_z;i+=_z){b[i>>5]|=(s.charCodeAt(i/8)&m)<<(32-_z-i%32);}return b;}function _h(k,d){var b=_b(k);if(b.length>16){b=_c(b,k.length*_z);}var p=[16],o=[16];for(var i=0;i<16;i++){p[i]=b[i]^0x36363636;o[i]=b[i]^0x5C5C5C5C;}var h=_c(p.concat(_b(d)),512+d.length*_z);return _c(o.concat(h),512+160);}function _n(b){var t="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",s='';for(var i=0;i<b.length*4;i+=3){var r=(((b[i>>2]>>8*(3-i%4))&0xFF)<<16)|(((b[i+1>>2]>>8*(3-(i+1)%4))&0xFF)<<8)|((b[i+2>>2]>>8*(3-(i+2)%4))&0xFF);for(var j=0;j<4;j++){if(i*8+j*6>b.length*32){s+=_p;}else{s+=t.charAt((r>>6*(3-j))&0x3F);}}}return s;}function _x(k,d){return _n(_h(k,d));}return _x(k,d);
}
var replyToId = input.reply_to_id;
var status = input.status_text;
//create nonce
function generateRandomString(desiredLengthOfRandomString) {
var result = '';
var possibleCharactersForRandomString = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
for( var i=0; i < desiredLengthOfRandomString; i++ )
result += possibleCharactersForRandomString.charAt(Math.floor(Math.random() * possibleCharactersForRandomString.length));
return result;
}
var randomString = generateRandomString(32);
var nonce = new Buffer(randomString).toString('base64');
//create timestamp
var timestamp = Math.floor(new Date() / 1000);
//create the signature
var signatureParameterString = 'in_reply_to_status_id=' + replyToId + '&status=' + status + '&oauth_consumer_key=' + twitterApplicationConsumerKey + '&oauth_nonce=' + encodeURIComponent(nonce) + '&oauth_signature_method=HMAC-SHA1&oauth_timestamp=' + timestamp + '&oauth_token=' + twitterApplicationAccessToken + '&oauth_version=1.0';
var signatureBaseString = 'POST&https%3A%2F%2Fapi.twitter.com%2F1.1%2Fstatuses%2Fupdate.json&' + encodeURIComponent(signatureParameterString);
var signingKey = encodeURIComponent(twitterApplicationConsumerSecret) + '&' + encodeURIComponent(twitterApplicationAccessTokenSecret);
var signature = b64_hmac_sha1(signingKey, signatureBaseString);
var apiUrl = 'https://api.twitter.com/1.1/statuses/update.json?in_reply_to_status_id=' + replyToId + '&status=' + status;
var oauthString = 'OAuth oauth_consumer_key="' + twitterApplicationConsumerKey + '", oauth_nonce="' + encodeURIComponent(nonce) + '", oauth_signature="' + encodeURIComponent(signature) + '", oauth_signature_method="HMAC-SHA1", oauth_timestamp="' + timestamp + '", oauth_token="' + twitterApplicationAccessToken + '", oauth_version="1.0"';
fetch(apiUrl, {
method: 'POST',
headers: {
'Authorization': oauthString
}
})
.then(function(res) {
return res.json();
})
.then(function(body) {
var output = body;
callback(null, output);
})
.catch(callback);
For some reason, I keep on getting error message: "Could not authenticate you" although the same code worked for performing a "like".
Not sure what am I doing wrong?

Zapier Code (JS) + Twitter API - POST favorites/create

I have recently came across this JS code for Zapier by #ReganStarr to create a "like tweet" action for any given tweet_id. I'm no expert but it sure looks fine (no error messages either), nevertheless, for some reason it doesn't work!
Would appreciate a lot if an experienced Zapier + JS eye can identify why isn't it working.
here is the code:
var twitterApplicationConsumerKey = 'MyTwitterConsumerKey';
var twitterApplicationConsumerSecret = 'MyTwitterConsumerSecret';
var twitterApplicationAccessToken = 'MyTwitterAccessToken';
var twitterApplicationAccessTokenSecret = 'MyTwitterTokenSecret';
// That's it. No need to edit anything below.
function b64_hmac_sha1(k,d,_p,_z){
if(!_p){_p='=';}if(!_z){_z=8;}function _f(t,b,c,d){if(t<20){return(b&c)|((~b)&d);}if(t<40){return b^c^d;}if(t<60){return(b&c)|(b&d)|(c&d);}return b^c^d;}function _k(t){return(t<20)?1518500249:(t<40)?1859775393:(t<60)?-1894007588:-899497514;}function _s(x,y){var l=(x&0xFFFF)+(y&0xFFFF),m=(x>>16)+(y>>16)+(l>>16);return(m<<16)|(l&0xFFFF);}function _r(n,c){return(n<<c)|(n>>>(32-c));}function _c(x,l){x[l>>5]|=0x80<<(24-l%32);x[((l+64>>9)<<4)+15]=l;var w=[80],a=1732584193,b=-271733879,c=-1732584194,d=271733878,e=-1009589776;for(var i=0;i<x.length;i+=16){var o=a,p=b,q=c,r=d,s=e;for(var j=0;j<80;j++){if(j<16){w[j]=x[i+j];}else{w[j]=_r(w[j-3]^w[j-8]^w[j-14]^w[j-16],1);}var t=_s(_s(_r(a,5),_f(j,b,c,d)),_s(_s(e,w[j]),_k(j)));e=d;d=c;c=_r(b,30);b=a;a=t;}a=_s(a,o);b=_s(b,p);c=_s(c,q);d=_s(d,r);e=_s(e,s);}return[a,b,c,d,e];}function _b(s){var b=[],m=(1<<_z)-1;for(var i=0;i<s.length*_z;i+=_z){b[i>>5]|=(s.charCodeAt(i/8)&m)<<(32-_z-i%32);}return b;}function _h(k,d){var b=_b(k);if(b.length>16){b=_c(b,k.length*_z);}var p=[16],o=[16];for(var i=0;i<16;i++){p[i]=b[i]^0x36363636;o[i]=b[i]^0x5C5C5C5C;}var h=_c(p.concat(_b(d)),512+d.length*_z);return _c(o.concat(h),512+160);}function _n(b){var t="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",s='';for(var i=0;i<b.length*4;i+=3){var r=(((b[i>>2]>>8*(3-i%4))&0xFF)<<16)|(((b[i+1>>2]>>8*(3-(i+1)%4))&0xFF)<<8)|((b[i+2>>2]>>8*(3-(i+2)%4))&0xFF);for(var j=0;j<4;j++){if(i*8+j*6>b.length*32){s+=_p;}else{s+=t.charAt((r>>6*(3-j))&0x3F);}}}return s;}function _x(k,d){return _n(_h(k,d));}return _x(k,d);
}
var tweetId = input.tweet_id;
//create nonce
function generateRandomString(desiredLengthOfRandomString) {
var result = '';
var possibleCharactersForRandomString = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
for( var i=0; i < desiredLengthOfRandomString; i++ )
result += possibleCharactersForRandomString.charAt(Math.floor(Math.random() * possibleCharactersForRandomString.length));
return result;
}
var randomString = generateRandomString(32);
var nonce = new Buffer(randomString).toString('base64');
//create timestamp
var timestamp = Math.floor(new Date() / 1000);
//create the signature
var signatureParameterString = 'id=' + tweetId + '&oauth_consumer_key=' + twitterApplicationConsumerKey + '&oauth_nonce=' + encodeURIComponent(nonce) + '&oauth_signature_method=HMAC-SHA1&oauth_timestamp=' + timestamp + '&oauth_token=' + twitterApplicationAccessToken + '&oauth_version=1.0';
var signatureBaseString = 'POST&https%3A%2F%2Fapi.twitter.com%2F1.1%2Ffavorites%2Fcreate.json&' + encodeURIComponent(signatureParameterString);
var signingKey = encodeURIComponent(twitterApplicationConsumerSecret) + '&' + encodeURIComponent(twitterApplicationAccessTokenSecret);
var signature = b64_hmac_sha1(signingKey, signatureBaseString);
var apiUrl = 'https://api.twitter.com/1.1/favorites/create.json?id=' + tweetId;
var oauthString = 'OAuth oauth_consumer_key="' + twitterApplicationConsumerKey + '", oauth_nonce="' + encodeURIComponent(nonce) + '", oauth_signature="' + encodeURIComponent(signature) + '", oauth_signature_method="HMAC-SHA1", oauth_timestamp="' + timestamp + '", oauth_token="' + twitterApplicationAccessToken + '", oauth_version="1.0"';
fetch(apiUrl, {
method: 'POST',
headers: {
'Authorization': oauthString
}
})
.then(function(res) {
return res.json();
})
.then(function(body) {
var output = body;
callback(null, output);
})
.catch(callback);
Thanks :-)

I just tried the code you posted and it worked for me.
You might double-check that you have your Access Levels set to "read and write" for your app at https://apps.twitter.com/ so that the 4 variables you include at the top of your code have the correct permissions.
And also make sure that you pass in tweet_id in the Input Data of the Zapier code step. (screenshot)

AWS IoT: Subscribe to Topic in Browser

I'm currently developing a Serverless App with AWS.
I want to subscribe to a topic using plain JavaScript (No Node.js, React, Angular etc.)
The IoT and IoTData SDK's doesn't support a "subscribe to topic" function.
To achieve this, i need to implement the aws-iot-device sdk, via require('aws-iot-device') (which i can't use in plain JS).
Unfortunatly this SDK only works with runtimes like Node.js or Browserify.
So how can someone subscribe to a topic from browser? Is there a way to implement the SDK into plain JS?
Thanks in advance

This is how its done, works perfectly fine:
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.11.2/moment.min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/components/core-min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/components/hmac-min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/components/sha256-min.js" type="text/javascript"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/paho-mqtt/1.0.1/mqttws31.min.js" type="text/javascript"></script>
cp this libaries into your html.
function SigV4Utils(){}
SigV4Utils.sign = function(key, msg) {
var hash = CryptoJS.HmacSHA256(msg, key);
return hash.toString(CryptoJS.enc.Hex);
};
SigV4Utils.sha256 = function(msg) {
var hash = CryptoJS.SHA256(msg);
return hash.toString(CryptoJS.enc.Hex);
};
SigV4Utils.getSignatureKey = function(key, dateStamp, regionName, serviceName) {
var kDate = CryptoJS.HmacSHA256(dateStamp, 'AWS4' + key);
var kRegion = CryptoJS.HmacSHA256(regionName, kDate);
var kService = CryptoJS.HmacSHA256(serviceName, kRegion);
var kSigning = CryptoJS.HmacSHA256('aws4_request', kService);
return kSigning;
};
function createEndpoint(regionName, awsIotEndpoint, accessKey, secretKey) {
var time = moment.utc();
var dateStamp = time.format('YYYYMMDD');
var amzdate = dateStamp + 'T' + time.format('HHmmss') + 'Z';
var service = 'iotdevicegateway';
var region = regionName;
var secretKey = secretKey;
var accessKey = accessKey;
var algorithm = 'AWS4-HMAC-SHA256';
var method = 'GET';
var canonicalUri = '/mqtt';
var host = awsIotEndpoint;
var credentialScope = dateStamp + '/' + region + '/' + service + '/' + 'aws4_request';
var canonicalQuerystring = 'X-Amz-Algorithm=AWS4-HMAC-SHA256';
canonicalQuerystring += '&X-Amz-Credential=' + encodeURIComponent(accessKey + '/' + credentialScope);
canonicalQuerystring += '&X-Amz-Date=' + amzdate;
canonicalQuerystring += '&X-Amz-SignedHeaders=host';
var canonicalHeaders = 'host:' + host + '\n';
var payloadHash = SigV4Utils.sha256('');
var canonicalRequest = method + '\n' + canonicalUri + '\n' + canonicalQuerystring + '\n' + canonicalHeaders + '\nhost\n' + payloadHash;
var stringToSign = algorithm + '\n' + amzdate + '\n' + credentialScope + '\n' + SigV4Utils.sha256(canonicalRequest);
var signingKey = SigV4Utils.getSignatureKey(secretKey, dateStamp, region, service);
var signature = SigV4Utils.sign(signingKey, stringToSign);
canonicalQuerystring += '&X-Amz-Signature=' + signature;
canonicalQuerystring += '&X-Amz-Security-Token=' + encodeURIComponent(AWS.config.credentials.sessionToken);
return 'wss://' + host + canonicalUri + '?' + canonicalQuerystring;
}
var endpoint = createEndpoint(
'eu-central-1', // YOUR REGION
'xxxxxx.iot.eu-central-1.amazonaws.com', // YOUR IoT ENDPOINT
accesskey, // YOUR ACCESS KEY
secretkey); // YOUR SECRET ACCESS KEY
var clientId = Math.random().toString(36).substring(7);
var client = new Paho.MQTT.Client(endpoint, clientId);
var connectOptions = {
useSSL: true,
timeout: 3,
mqttVersion: 4,
onSuccess: subscribe
};
client.connect(connectOptions);
client.onMessageArrived = onMessage;
client.onConnectionLost = function(e) {
console.log(e)
};
function subscribe() {
client.subscribe("my/things/something");
console.log("subscribed");
}
function onMessage(message) {
var status = JSON.parse(message.payloadString);
}
With this code, you can subscribe to IoT Topics in plain client side JavaScript. No Node.js, React.js or similar is needed!

You can use paho js or mqttjs in the browser. The aws-iot-device sdk for javascript is a wrapper around mqttjs.