is it possible to stop the selenium webdriver without stopping node?
I have following issue:
I try to create a API tool that does some web automation when getting a get request. So I am basically running selenium webdriver on a get request to /start via Express. I want the tool to check for different elements and when it somehow fails I want it to stop selenium but NOT the node instance (since a new get request could be send).
This is my code so far:
"use strict";
const webdriver = require('selenium-webdriver'),
Express = require('express'),
By = webdriver.By,
until = webdriver.until,
Keys = webdriver.Key,
app = new Express();
app.get("/automate", (req, res) => {
start(res);
});
function start(res) {
const driver = new webdriver.Builder().forBrowser('chrome').build();
driver.get('https://www.google.com/');
// # --- foo --- #
let errMessage = {pos: "FOO", message: "Ooops friendly robot has some troubles!"}
checkStep("#foo", errMessage);
driver.findElement(By.id("foo"))
.sendKeys("fooz");
// # --- bar --- #
errMessage = {pos: "BAR", message: "Ooops friendly robot has some troubles!"}
checkStep("#bar", errMessage);
driver.findElement(By.id("bar"))
.sendKeys("baz");
// etc…
function checkStep(selector, errMessage) {
driver.findElement(By.css(selector))
.then(() => {
console.log(`${selector} => found`);
})
.catch(err => {
console.log(`Error: ${err}`);
res.send(errMessage);
driver.quit();
});
}
}
app.get("*", (req, res) => {
res.send("Hello World");
});
// start the server
const port = process.env.PORT || 3000;
const env = process.env.NODE_ENV || 'production';
app.listen(port, err => {
if (err) { return console.error(err); }
console.info(`Server running on http://localhost:${port} [${env}]`);
});
it is actually working so far that when selenium do not find the element the response from the API is correct. In Selenium I get back:
{
"pos": "FOO",
"message": "Ooops friendly robot has some troubles!"
}
So far all good.
BUT unfortunately stopping selenium is also stopping Node from running.
The error I get is following:
throw error;
^
WebDriverError: no such session
(Driver info: chromedriver=2.30.477690 (c53f4ad87510ee97b5c3425a14c0e79780cdf262),platform=Ma
c OS X 10.12.5 x86_64)
at WebDriverError
Please help, thank you!
ps: I am not using webdriverio as you can see I use this package: https://www.npmjs.com/package/selenium-webdriver
Ok, I got this working. It’s a bit difficult solution but it works:
Using Child Processes
Basically, every time the app gets a get request to /automate it will now create a child process in node which runs the selenium scripts (a child process is kind of like using another thread. Here is a very good tutorial on child processes):
index.js
"use strict";
const Express = require('express');
const { spawn } = require('child_process');
const data = require('./data.json');
const app = new Express();
app.get("/automate", (req, res) => {
const child = spawn(
process.execPath,
[`${__dirname}/test.js`, JSON.stringify(data)],
{ stdio: ['inherit', 'inherit', 'inherit', 'pipe'] }
);
child.stdio[3].on('data', data => {
const response = JSON.parse(data.toString());
res.send(response);
console.log(response);
child.kill();
});
});
app.get("*", (req, res) => {
res.send("Hello World");
});
const port = process.env.PORT || 3000;
const env = process.env.NODE_ENV || 'production';
app.listen(port, err => {
if (err) { return console.error(err); }
console.info(`Server running on http://localhost:${port} [${env}]`);
});
test.js
"use strict";
// hook with argument 3, that is "pipe" from parent
const Net = require('net'),
pipe = new Net.Socket({ fd: 3 });
const data = JSON.parse(process.argv[2]);
const webdriver = require('selenium-webdriver'),
By = webdriver.By,
until = webdriver.until,
Keys = webdriver.Key;
function start() {
const driver = new webdriver.Builder().forBrowser('chrome').build();
driver.get('https://www.google.com/');
// # --- foo --- #
let errMessage = {pos: "lst-ib", message: "Ooops friendly robot has some troubles!"}
checkStep("#lst-ib")
.sendKeys("fooz");
driver.get('https://www.facebook.com/');
driver.get('https://www.google.com/');
driver.get('https://www.facebook.com/');
// # --- bar --- #
errMessage = {pos: "BAR", message: "Ooops friendly robot has some troubles!"}
checkStep("#bar")
.sendKeys("baz");
function checkStep(selector) {
driver.findElement(By.css(selector))
.then(() => {
console.log(`${selector} => found`);
})
.catch(err => {
console.log(`${selector} => not found`);
publish(errMessage);
driver.quit();
});
}
}
function publish(message) {
pipe.write(JSON.stringify(message));
}
start();
It is working like a charm: on each request opening a new child process and killing that child process if it sends some message while also responding with the message to the client. Like this you can easily have several selenium instances simultaneously.
You’re welcome.
ps: If you hate all this asyncron stuff from Selenium webdriver-sync seems like a good choice. It basically wraps the selenium code to be syncon instead of asyncron. Like that I am able to use try {} catch {} and to driver.quit(); without any errors for code that comes later. (But this comes with a disadvantage: it is actually blocking your other nodejs code.)
Related
I'm trying to make a way to boot up a Minecraft server from nodejs, but I'm having trouble making a way to run commands from nodejs.
const { spawn } = require('node:child_process')
const express = require('express');
const bodyParser = require('body-parser');
const app = express();
const fs = require('fs');
app.get('/start', (req, res) => {
fs.writeFile('minecraftstatus.txt', 'on', (err) => {
if (err) throw err;
});
const command = spawn('java', ['-jar', '-Xms2048M','-Xmx2048M', '-Dfile.encoding=utf8', 'server.jar', 'nogui'])
// the `data` event is fired every time data is
// output from the command
command.stdout.on('data', output => {
// the output data is captured and printed in the callback
fs.appendFile('console.txt', ("\n" + output.toString()), 'utf-8', err => {
console.log(err)
})
console.log("Output: ", output.toString())
})
res.status(200).send("OK")
});
app.listen(80, () => {
console.log('Server started on port 80');
});
From what you see above, whenever a user sends a GET request, it sends a command and appends any output to a text file. I need to make a way in order to send commands to Minecraft. I need to send commands to the same shell that nodejs ran the command.
I've tried this:
app.get('/mcstop', (req, res) => {
try {
const command2 = spawn('/stop')
// the `data` event is fired every time data is
// output from the command
command2.stdout.on('data', output => {
// the output data is captured and printed in the callback
console.log("Output: ", output.toString())
})
res.status(200).send("OK")
}
catch {
console.log("Oh no...")
}
});
Where it sends /stop to the shell, but it seems like it isn't being ran on the same shell as where the Minecraft server was created from.
How could I achieve this?
I've been following a tutorial on how to connect to a mongoDB collection. The tutorial works fine but I'm trying the same code in a project I'm working on and have been getting the following error constantly:
./node_modules/raw-body/index.js
Module not found: Can't resolve 'async_hooks' in '*:\*\*\Desktop\Projects\testing-area\node_modules\raw-body'
I've tried:
-deleting node_modules and then running npm install
-running npm update to bring all dependencies to the latest version
-updating npm itself
I've read that async_hooks is used for backend work and if you try to use it in the frontend, it can cause this issue. Problem is, I don't really know a way around it.
Here's the code I'm trying to use to connect to the mongodb collection:
//give functions of mongo db to MongoClient
const { MongoClient } = require('mongodb')
let dbConnection
const bark = (input) => {
console.log(input)
}
module.exports = {
connectToDb: (cb) => {
MongoClient.connect("mongodb://localhost:27017/Treasures")
.then((client) => {
dbConnection = client.db()
return cb()
})
.catch(err => {
bark("----------")
bark("Pants shat when trying to connect to DB:\n")
bark(err)
return cb(err)
bark("----------")
})
},
getDb: () => dbConnection
}
And then in a component I have this, to try and get the data from the collection:
// Imports/Requires for mongoDb connection
const { ObjectID } = require("bson");
const express = require("express");
const { connectToDb, getDb } = require("../../db")
// COMPONENT STARTS HERE:
export const TreasureGen = () => {
//init app and middleware
const app = express();
//db connection
let db
connectToDb((err) => {
if(!err)
{
app.listen(3000, () => {
bark("App listening on port 3000")
})
db = getDb()
}
})
I'm trying to set up testing for various routes in my Express server that require connectivity to my MongoDB database.
I'm not sure how to structure the Jest file in order to allow for testing. In my normal index.js file, I'm importing the app, and running app.listen within the connect .then call, like this:
const connect = require("../dbs/mongodb/connect");
connect()
.then(_ => {
app.listen(process.env.PORT, _ => logger.info('this is running')
})
.catch(_ => logger.error('The app could not connect.');
I've tried running the same setup in my test.js files, but it's not working.
For example:
const connect = require("../dbs/mongodb/connect");
const request = require("supertest");
const runTests = () => {
describe("Test the home page", () => {
test("It should give a 200 response.", async () => {
let res = await request(app).get("/");
expect(res.statusCode).toBe(200);
});
});
};
connect()
.then(_ => app.listen(process.env.PORT))
.then(runTests)
.catch(err => {
console.error(`Could not connect to mongodb`, err);
});
How is it possible to wait for a connection to MongoDB before running my tests?
So, turns out there were a few changes that I had to make. Firstly, I had to load in my .env file before running the tests. I did this by creating a jest.config.js file in the root of my project:
module.exports = {
verbose: true,
setupFiles: ["dotenv/config"]
};
Then within the actual testing suite, I'm running beforeEach to connect to the MongoDB server.
const connect = require("../dbs/mongodb/connect");
const app = require("../app");
const request = require("supertest");
beforeEach(async() => {
await connect();
});
describe("This is the test", () => {
test("This should work", async done => {
let res = await request(app).get("/home");
expect(res.statusCode).toBe(200);
done();
})
});
I'm kinda new to module creation and was wondering about module.exports and waiting for async functions (like a mongo connect function for example) to complete and exporting the result. The variables get properly defined using async/await in the module, but when trying to log them by requiring the module, they show up as undefined. If someone could point me in the right direction, that'd be great. Here's the code I've got so far:
// module.js
const MongoClient = require('mongodb').MongoClient
const mongo_host = '127.0.0.1'
const mongo_db = 'test'
const mongo_port = '27017';
(async module => {
var client, db
var url = `mongodb://${mongo_host}:${mongo_port}/${mongo_db}`
try {
// Use connect method to connect to the Server
client = await MongoClient.connect(url, {
useNewUrlParser: true
})
db = client.db(mongo_db)
} catch (err) {
console.error(err)
} finally {
// Exporting mongo just to test things
console.log(client) // Just to test things I tried logging the client here and it works. It doesn't show 'undefined' like test.js does when trying to console.log it from there
module.exports = {
client,
db
}
}
})(module)
And here's the js that requires the module
// test.js
const {client} = require('./module')
console.log(client) // Logs 'undefined'
I'm fairly familiar with js and am still actively learning and looking into things like async/await and like features, but yeah... I can't really figure that one out
You have to export synchronously, so its impossible to export client and db directly. However you could export a Promise that resolves to client and db:
module.exports = (async function() {
const client = await MongoClient.connect(url, {
useNewUrlParser: true
});
const db = client.db(mongo_db);
return { client, db };
})();
So then you can import it as:
const {client, db} = await require("yourmodule");
(that has to be in an async function itself)
PS: console.error(err) is not a proper error handler, if you cant handle the error just crash
the solution provided above by #Jonas Wilms is working but requires to call requires in an async function each time we want to reuse the connection. an alternative way is to use a callback function to return the mongoDB client object.
mongo.js:
const MongoClient = require('mongodb').MongoClient;
const uri = "mongodb+srv://<user>:<pwd>#<host and port>?retryWrites=true";
const mongoClient = async function(cb) {
const client = await MongoClient.connect(uri, {
useNewUrlParser: true
});
cb(client);
};
module.exports = {mongoClient}
then we can use mongoClient method in a diffrent file(express route or any other js file).
app.js:
var client;
const mongo = require('path to mongo.js');
mongo.mongoClient((connection) => {
client = connection;
});
//declare express app and listen....
//simple post reuest to store a student..
app.post('/', async (req, res, next) => {
const newStudent = {
name: req.body.name,
description: req.body.description,
studentId: req.body.studetId,
image: req.body.image
};
try
{
await client.db('university').collection('students').insertOne({newStudent});
}
catch(err)
{
console.log(err);
return res.status(500).json({ error: err});
}
return res.status(201).json({ message: 'Student added'});
};
I am using xterm.js in my web project to have a terminal on the web page. Every time I refresh my page or reconnect socket when a socket connection is broken due to internet fluctuation from the client. The current PWD directory is lost and it falls to specified CWD directory which is user home in my case. So again I have to do cd where I was working.
How can I connect and remain at same PWD where I was last time before page refreshing or socket disconnect?
One of the things I tried is to store term object and connect through the same object when reconnecting if it is already present. Not deleting process and object in on WebSocket disconnect.
var http = require('http');
var express = require('express');
var app = express();
var expressWs = require('express-ws')(app);
var pty = require('node-pty');
var cors = require('cors');
app.use(cors());
app.options('*', cors());
var terminals = {}; //global terminals
function getUser(token) {
return new Promise((resolve, reject) => {
try {
return http.get({
host: '',
path: '',
headers: {'token': token}
}, function(response) {
// Continuously update stream with data
var body = '';
response.on('data', function(d) {
body += d;
});
response.on('end', function() {
return resolve(JSON.parse(body));
});
});
} catch (err) {
console.log('Api failed');
console.log(err);
reject;
}
})
}
app.ws('/terminals/:user_id', function (ws, req) {
try {
getUser(req.params.user_id) /* cheking with api if user exist in my database*/
.then(user_info => {
if(terminals[parseInt(req.params.user_id)]){
var term = terminals[parseInt(req.params.user_id)];
}else {
var term = pty.spawn(process.platform === 'win32' ? 'cmd.exe' : 'bash', [], {
name: 'xterm-color',
cwd: cwd,
env: process.env
});
terminals[parseInt(req.params.user_id)] = term;
}
term.on('data', function(data) {
ws.send(data);
});
ws.on('message', function(msg) {
term.write(msg);
});
ws.on('close', function () {
// process.kill(term.pid);
// delete terminals[parseInt(req.params.pid)];
// delete logs[req.params.pid];
});
})
.catch(err => {
})
} catch (err) {
console.log('Terminal webSocket failed');
console.log(err);
}
});
app.listen(3000);
This is not working for me. This gets me connect only first time but when I refresh my page terminal does not connect with existing store object.
Also, this has a problem if the spawned process is killed by the system but it still remains in javascript object and script try to reconnect with same term object it will fail.
Any guidelines how to achieve reconnect with same PWD.
Details
OS version: Mac OS ,
xterm.js version: 2.2.3
This can be solved very easily by just updating the ~/.bashrc on server
Putting below two line in ~/.bashrc file worked for me
PROMPT_COMMAND+='printf %s "$PWD" > ~/.storepwd'
[ -s ~/.lastdirectory ] && cd `cat ~/.lastdirectory`
Ref Save last working directory on Bash logout