H Apologies,
This is going to be an incredibly beginner question - I have been trying to figure this out on my own this afternoon. I am only beginning coding in js for the first time today.
I am trying to create a script that will monitor Mixer's constellation server, receive a response when a stream goes live. (I have this bit working fine and when the streamer goes online it send a true message, when the streamer goes offline i get false).
const Carina = require('carina').Carina;
const ws = require('ws');
Carina.WebSocket = ws;
const channelId = xxxxxx;
const ca = new Carina({ isBot: true }).open();
ca.subscribe(`channel:${channelId}:update`, data => {
console.log(data.online);
});
I then would like it to trigger a POST query to using the maker script part of IFTTT to trigger an event there (such as flash my lights when my favourite streamer goes online) - I also have this script working fine!
var request = require("request");
request({
uri:
"https://maker.ifttt.com/trigger/streaming/with/key/xxxxxxxxxxxxxxxxxx",
method: "POST",
}, function(error, response, body) {
console.log(body);
});
Problem I have, is I have zero knowledge of js, as to have to merge the 2 together, so that when I receive a 'true' response from the Mixer constellation server, it runs the second part of the script.
I hope that you go easy on my lack of knowledge and I look thank you for your assistance.
i think you have to simply use a function in callback of another function like this:
const Carina = require('carina').Carina;
const ws = require('ws');
Carina.WebSocket = ws;
const channelId = xxxxxx;
const ca = new Carina({ isBot: true }).open();
var request = require("request");
ca.subscribe(`channel:${channelId}:update`, data => {
if(data.online){
request({
uri:
"https://maker.ifttt.com/trigger/streaming/with/key/xxxxxxxxxxxxxxxxxx",
method: "POST",
}, function(error, response, body) {
console.log(body);
});
}
});
Related
I am fetching data from different API with javascript's fetch API. But how can I find out how many bytes are sent on each request for analytics?
The request could be in any method.
I know that I can get the amount of bytes received with
response.headers["content-length"].
I need to find out a way to get the amount of bytes sent on the frontend (browser or mobile using React Native). Ideally, it would be the total size of the request, but just the size of the request body would be good enough.
You can get the value that will be set in the Content-Length header by reading the Request's body as text and checking the length of the returned string:
(async () => {
const formdata = new FormData();
const file = new Blob(["data".repeat(1024)])
formdata.append("key", file)
const req = new Request("/", { method: "POST", body: formdata });
// note that we .clone() the Request
// so that we can still use the original one with fetch()
console.log((await req.clone().text()).length);
fetch(req);
console.log("check the Network panel of your dev tools to see the sent header");
})();
However this only applies for requests where this header is sent, i.e not for GET and HEAD requests.
A quick solution that I used - a tiny middleware (I use Express):
const socketBytes = new Map();
app.use((req, res, next) => {
req.socketProgress = getSocketProgress(req.socket);
next();
});
/**
* return kb read delta for given socket
*/
function getSocketProgress(socket) {
const currBytesRead = socket.bytesRead;
let prevBytesRead;
if (!socketBytes.has(socket)) {
prevBytesRead = 0;
} else {
prevBytesRead = socketBytes.get(socket).prevBytesRead;
}
socketBytes.set(socket, {prevBytesRead: currBytesRead})
return (currBytesRead-prevBytesRead)/1024;
}
And then you can use req.socketProgress in your middlewares.
After connecting and wiring the Shelly2.5 with my shutter, trying to connect it with Siri.
Decided to do this with Scriptable app and then connect Siri commands to it, so it will run.
Currently have an issue to send the request from the Scriptable app as the code is written below, when i tried to fire it from Postman it works.
// # open shutter
let url = "https://domain.shelly.cloud";
let suffix ="/device/relay/roller/control/";
let auth_key = "AAAABBBBCCCDDDEEEEFFFFFF____EXAMPLE_TOKEN___AAAABBBBCCCDDDEEEEFFFFFF";
let channel = 0;
let turn = "on";
let direction = "open";
let id = "C45bbe75f1bd";
let body = {
"auth_key":auth_key,
"id": id,
"direction":direction
};
// console.log(body);
let req = new Request(url + suffix);
// console.log(url+suffix);
req.method = "POST";
req.body = body;
req.headers = { "Content-Type":"application/x-www-form-urlencoded" };
// req.body = JSON.stringify(body)
let json = await req.loadJSON()
console.log(json);
the current response:
2021-09-13 11:20:46: {"isok":false,"errors":{"invalid_header":"Unauthorized! Wrong authorization header provided!","invalid_token":"The login information is invalid! Please login again!"}}
please notice that i change the real token and the real sub domain for shelly cloud.
It will be grate if someone know how to fix this, Thanks
looks like the Shelly expect form-encoded body. Try this
let form = Object.keys(body).map( k => `${k}=${encodeURIComponent(body[k])}`).join('&')
req.body = form
File called testing.js
I can do whatever I like with the data in saveWeatherData but cannot call this function and return the data without getting 'undefined'
For example if i tried the below code in saveWeatherData it will print out the summary as expected...
console.log(The summary of the weather today is: ${dataArray[0]});
However I want to use these values within another file such as a server file that when connected to will display weather summary temperature etc.
So I need to return an array with these values in it so that I can call this function and get my data stored in an array for further use.
I know that the reason the array --dataArray is returning undefined is because asynchronous code.
The array is returned before we have gotten the data using the callback.
My question, is there anyway to do what I am trying to do?
I tried my best to explain the problem and what I want to do, hopefully its understandable.
Would I have to use a callback inside of a callback? To callback here to return the data when its been fetched?
I just cant get my head about it and have tried multiple things to try and get the result I am looking for.
My last idea and something i would prefer not to do is the use the 'fs' module to save the data to a text or json file for use in my other files through reading the data from the saved file...
I feel im close but cant get over the last hurdle, so ive decided to ask for a little help, even just point me on the right track and Ill continue to try and figure it out.
Phew...
Thank you for your time!
const request = require("request");
let dataArray = [];
let saveWeatherData = function(weatherData) {
dataArray = weatherData;
return dataArray;
};
let getWeatherData = function(callback) {
request({
url: `https://api.forecast.io/forecast/someexamplekey/1,-1`,
json: true
}, (error, response, body) => {
//Creating array to hold weather data until we can save it using callback...
let array = [];
if (error) {
console.log("Unable to connect with Dark Sky API servers.")
}
else {
console.log(`Successfully connected to Dark Sky API servers!\n`);
array.push(body.currently.summary, body.currently.temperature, body.currently.apparentTemperature, body.currently.windSpeed, body.currently.windBearing);
callback(array);
}
});
};
getWeatherData(saveWeatherData);
module.exports = {
saveWeatherData
};
My Other File...
File called server.js
const http = require("http");
const testing = require("./testing");
function onRequest(request, response){
let data = testing.saveWeatherData();
console.log(`A user made a request: ${request.url}`);
response.writeHead(200, {"context-type": "text/plain"});
response.write("<!DOCTYPE html>");
response.write("<html>");
response.write("<head>");
response.write("<title>Weather</title>");
response.write("</head>");
response.write("<body>");
response.write("Weather summary for today: " + data[0]);
response.write("</body>");
response.write("</html>");
response.end();
}
http.createServer(onRequest).listen(8888);
console.log("Server is now running on port 8888...");
I'm still not sure about what are you trying to do. However, I think you're not exporting what you suppose to be exporting. To avoid the use of so many callbacks you may use async/await.
Change this part of your server.js
async function onRequest(request, response) {
let data = await testing.getWeatherData();
console.log(`A user made a request: ${request.url}`);
response.writeHead(200, { 'context-type': 'text/plain' });
response.write('<!DOCTYPE html>');
response.write('<html>');
response.write('<head>');
response.write('<title>Weather</title>');
response.write('</head>');
response.write('<body>');
response.write('Weather summary for today: ' + data[0]);
response.write('</body>');
response.write('</html>');
response.end();
}
And this of your testing.
let getWeatherData = function() {
return new Promise(resolve =>
request(
{
url: `https://api.darksky.net/forecast/someexamplekey/1,-1`,
json: true
},
(error, response, body) => {
//Creating array to hold weather data until we can save it using callback...
let array = [];
if (error) {
console.log('Unable to connect with Dark Sky API servers.');
} else {
console.log(`Successfully connected to Dark Sky API servers!\n`);
array.push(
body.currently.summary,
body.currently.temperature,
body.currently.apparentTemperature,
body.currently.windSpeed,
body.currently.windBearing
);
resolve(array);
}
}
)
);
};
module.exports = {
getWeatherData
};
It will check for new Weather in each request. If you want to save the result to avoid checking every single time you might need to do something else. But I think for a weather app the important is to keep it updated.
I'm trying to make a .js file that will constantly have the price of bitcoin updated (every five minutes or so). I've tried tons of different ways to web scrape but they always output with either null or nothing. Here is my latest code, any ideas?
var express = require('express');
var path = require('path');
var request = require('request');
var cheerio = require('cheerio');
var fs = require('fs');
var app = express();
var url = 'https://blockchain.info/charts/';
var port = 9945;
function BTC() {
request(url, function (err, res, body) {
var $ = cheerio.load(body);
var a = $(".market-price");
var b = a.text();
console.log(b);
})
setInterval(BTC, 300000)
}
BTC();
app.listen(port);
console.log('server is running on '+port);
It successfully says what port it's running on, that's not the problem. This example (when outputting) just makes a line break every time the function happens.
UPDATE:
I changed the new code I got from Wartoshika and it stopped working, but im not sure why. Here it is:
function BTCPrice() {
request('https://blockchain.info/de/ticker', (error, response, body) => {
const data = JSON.parse(body);
var value = (parseInt(data.USD.buy, 10) + parseInt(data.USD.sell, 10)) / 2;
return value;
});
};
console.log(BTCPrice());
If I have it console.log directly from inside the function it works, but when I have it console.log the output of the function it outputs undefined. Any ideas?
I would rather use a JSON api to get the current bitcoin value instead of an HTML parser. With the JSON api you get a strait forward result set that is parsable by your browser.
Checkout Exchange Rates API
Url will look like https://blockchain.info/de/ticker
Working script:
const request = require('request');
function BTC() {
// send a request to blockchain
request('https://blockchain.info/de/ticker', (error, response, body) => {
// parse the json answer and get the current bitcoin value
const data = JSON.parse(body);
value = (parseInt(data.THB.buy, 10) + parseInt(data.THB.sell, 10)) / 2;
console.log(value);
});
}
BTC();
Using the value as callback:
const request = require('request');
function BTC() {
return new Promise((resolve) => {
// send a request to blockchain
request('https://blockchain.info/de/ticker', (error, response, body) => {
// parse the json answer and get the current bitcoin value
const data = JSON.parse(body);
value = (parseInt(data.THB.buy, 10) + parseInt(data.THB.sell, 10)) / 2;
resolve(value);
});
});
}
BTC().then(val => console.log(val));
As the other answer stated, you should really use an API. You should also think about what type of price you want to request. If you just want a sort of index price that aggregates prices from multiple exchanges, use something like the CoinGecko API. Also if you need real-time data you need a websocket-based API, not a REST API.
If you need prices for a particular exchange, for example you're building a trading bot for one or more exchanges, you;ll need to communicate with each exchange's websoceket API directly. For that I would recommend something like the Coygo API, a node.js package that connects you directly to each exchange's real-time data feeds. You want something that doesn't add a middleman since that would add latency to your data.
I'm trying to download the lat/long locations of CCTV locations from the City of Baltimore website (project on the surveillance state) but not getting the console to log anything.
Here's the site:
and my code is:
const request = require('request');
const cheerio = require('cheerio');
let URL = 'https://data.baltimorecity.gov/Public-Safety/CCTV-Locations/hdyb-27ak/data'
let cameras = [];
request(URL, function(err, res, body) {
if(!err && res.statusCode == 200) {
let $ = cheerio.load(body);
$('div.blist-t1-c140113793').each(function() {
let camera = $(this);
let location = camera.text();
console.log(location);
cameras.push(location);
});
console.log(cameras);
}
});
I've tried setting the to blist-t1-c140113793 and blist-td blist-t1-c140113793 but neither has worked.
That's because data for those divs are loaded asynchronously, after the page was rendered. JavaScript is not executed by Cherrio, or any other such library. You'll need either to analyze network traffic and understand which HTTP call loads this data, or use something like Selenium, that actually executes JavaScript inside the browser.