I'm trying to connect a Node.js app with a PostgreSQL server. It seems that no matter what I use, I end up with the same error:
bundle.js:16177 ERROR: TypeError: net.Stream is not a constructor
at new Connection (bundle.js:10133)
at new Client (bundle.js:9704)
at Object.create (bundle.js:11308)
at Pool._createResource (bundle.js:510)
at Pool.dispense [as _dispense] (bundle.js:498)
at Pool.acquire (bundle.js:573)
at Pool.pool.connect (bundle.js:11359)
at PG.connect (bundle.js:10876)
at bundle.js:1642
At first I was declaring a new pg.Client() like the example in the documentation here, but got the above error discovered that might be a bad idea according to this stack overflow post.
I tried using pg.connect():
var pg = require('pg'); //postgresql dependency
var connectionString = "postgres://postgres:thisissuchagoodpassword#PostgreSQL/localhost:5432/Milestone1DB"
console.log("Initiating...");
//var connectionString = "postgres://postgres:thisissuchagoodpassword#PostgreSQL9.6/localhost:5432/Milestone1DB";
//var client = new pg.Client();
//connect to the database
console.log("Attempting to connect to the database");
pg.connect(function (err, client, done)
{
if(err)
{
console.log("Error connecting to the database.");
throw err;
}
client.query("SELECT DISTINCT state FROM business ORDER BY state", function (err, result)
{
if(err)
{
console.log("Query resulted in an error.");
throw err;
}
console.log(result.rows[0]);
client.end(function (err)
{
if(err)
{
console.log("Error disconnecting from the databse.");
throw err;
}
});
});
});
Here is the pg-promise code that I tried:
var pgp = require('pg-promise');
var cn = {
host: 'localhost', // server name or IP address;
port: 5432,
database: 'Milestone1DB',
user: 'postgres',
password: 'thisissuchagoodpassword'
};
var db = pgp(cn); // database instance;
db.any("select distict state from business order by state;")
.then(data => {
console.log("DATA:", data);
})
.catch(error => {
console.log("ERROR:", error);
});
I must be missing something, but I don't know where to look. Thank you to anyone who can help me figure out what this error means.
Make sure you are not crossing a context boundary that is corrupting the net prototype chain and stripping away methods like Stream(). I ran into a similar unhandled Promise exception w Node 7.5 and pg-live-select. However it was intermittent because of the way the net reference was being passed around. I ended up using V8 inspector and putting a 'debugger' statement directly above line 13 in connection.js to catch the corruption.
node_modules/lib/connection.js:13
this.stream = config.stream || new net.Stream();
^
TypeError: net.Stream is not a constructor
at new Connection (node_modules/pg-live-select/node_modules/pg/lib/connection.js:13:34)
at new Client (node_modules/pg-live-select/node_modules/pg/lib/client.js:26:37)
at Object.create (node_modules/pg-live-select/node_modules/pg/lib/pool.js:27:24)
at Pool._createResource (node_modules/generic-pool/lib/generic-pool.js:325:17)
at Pool.dispense [as _dispense] (node_modules/generic-pool/lib/generic-pool.js:313:12)
at Pool.acquire (node_modules/generic-pool/lib/generic-pool.js:388:8)
at Pool.pool.connect (node_modules/pg-live-select/node_modules/pg/lib/pool.js:78:14)
at PG.connect (node_modules/pg-live-select/node_modules/pg/lib/index.js:49:8)
at LivePg._updateQuery (node_modules/pg-live-select/index.js:295:6)
at node_modules/pg-live-select/index.js:160:14
at Array.forEach (native)
at Timeout.performNextUpdate [as _onTimeout] (node_modules/pg-live-select/index.js:159:23)
at ontimeout (timers.js:365:14)
at tryOnTimeout (timers.js:237:5)
at Timer.listOnTimeout (timers.js:207:5)
Related
Does this Nodejs code look right? Is there anything missing?
const mysql = require('mysql');
const fs = require('fs');
var config =
{
host: 'mydemoserver.mysql.database.azure.com',
user: 'myadmin#mydemoserver',
password: 'your_password',
database: 'quickstartdb',
port: 3306,
ssl: {ca: fs.readFileSync("your_path_to_ca_cert_file_BaltimoreCyberTrustRoot.crt.pem")}
};
const conn = new mysql.createConnection(config);
conn.connect(
function (err) {
if (err) {
console.log("!!! Cannot connect !!! Error:");
throw err;
}
else {
console.log("Connection established.");
readData();
}
});
function readData(){
conn.query('SELECT * FROM inventory',
function (err, results, fields) {
if (err) throw err;
else console.log('Selected ' + results.length + ' row(s).');
for (i = 0; i < results.length; i++) {
console.log('Row: ' + JSON.stringify(results[i]));
}
console.log('Done.');
})
conn.end(
function (err) {
if (err) throw err;
else console.log('Closing connection.')
});
};
This is to go inside an Azure Function that reads data from a Azure for MySQL database.
When I run it inside the Kudu window by just typing node index.js it works
When I try and test it on there Azure Function Test Page it throws a Internal Server Error 500 with the following error message
Unable to determine function entry point. If multiple functions are exported, you must indicate the entry point, either by naming it 'run' or 'index', or by naming it explicitly via the 'entryPoint' metadata property.' Stack: Error: Worker was unable to load function ListBrands: 'Unable to determine function entry point. If multiple functions are exported, you must indicate the entry point, either by naming it 'run' or 'index', or by naming it explicitly via the 'entryPoint' metadata property.' at C:\Program Files (x86)\SiteExtensions\Functions\4.14.0\workers\node\dist\src\worker-bundle.js:2:13853 at t.LegacyFunctionLoader. (C:\Program Files (x86)\SiteExtensions\Functions\4.14.0\workers\node\dist\src\worker-bundle.js:2:14092) at Generator.next () at o (C:\Program Files (x86)\SiteExtensions\Functions\4.14.0\workers\node\dist\src\worker-bundle.js:2:12538) at processTicksAndRejections (node:internal/process/task_queues:96:5)
Thanks in advance
Todd
I have recently deployed my node.js API application on live server. I am getting these issue on live server.
I have googled it, but could not get any exact solution. Can anyone suggest how can i solve this problem?
{ Error: read ETIMEDOUT at TCP.onread (net.js:622:25) errno: 'ETIMEDOUT', code: 'ETIMEDOUT', syscall: 'read', fatal: true }
{ Error: Can't add new command when connection is in closed state at PoolConnection._addCommandClosedState }
I amd using the mysql connection pool like this
var mysql = require('mysql2');
var mysqlPool = mysql.createPool({
host: 'localhost',
user: 'root',
password: 'xyz',
database: 'xyz',
waitForConnections: true,
connectionLimit: 10,
queueLimit: 0
});
module.exports = mysqlPool;
I had a similar problem and ended up having to put the connection request in it's own .js file and import it into the controller-
connectionRequest.js
module.exports = function () {
let mysql = require('mysql2')
let connCreds = require('./connectionsConfig.json');
//Establish Connection to the DB
let connection = mysql.createConnection({
host: connCreds["host"],
user: connCreds['username'],
password: connCreds['password'],
database: connCreds['database'],
port: 3306
});
//Instantiate the connection
connection.connect(function (err) {
if (err) {
console.log(`connectionRequest Failed ${err.stack}`)
} else {
console.log(`DB connectionRequest Successful ${connection.threadId}`)
}
});
//return connection object
return connection
}
Once I did that I was able to import it into my query on the controller file like so
ControllerFile.js
let connectionRequest = require('../config/connectionRequest')
controllerMethod: (req, res, next) => {
//Establish the connection on this request
connection = connectionRequest()
//Run the query
connection.query("SELECT * FROM table", function (err, result, fields) {
if (err) {
// If an error occurred, send a generic server failure
console.log(`not successful! ${err}`)
connection.destroy();
} else {
//If successful, inform as such
console.log(`Query was successful, ${result}`)
//send json file to end user if using an API
res.json(result)
//destroy the connection thread
connection.destroy();
}
});
},
After a lot of messing around I was able to solve the problem by destroying the connection, waiting (this is the important page) and getting the connection again.
conn = await connPool.getConnection();
// We have error: Can't add new command when connection is in closed state
// I'm attempting to solve it by grabbing a new connection
if (!conn || !conn.connection || conn.connection._closing) {
winston.info('Connection is in a closed state, getting a new connection');
await conn.destroy(); // Toast that guy right now
sleep.sleep(1); // Wait for the connection to be destroyed and try to get a new one, you must wait! otherwise u get the same connection
conn = await connPool.connection.getConnection(); // get a new one
}
I am trying to learn Node.js and created a simple project to query the local database. But I get failed to look up an instance error message.
I have checked that the SQL Server services running in services.msc
I have verified TCP/IP is enabled
I have tried with the username and password and without it as well. I connect to localdb in SQL Server Management Studio as (localdb)\v11.0 and below is the screenshot of the properties
What am I doing incorrectly? What should be actual username and password? What should be the servername?
const sql = require('mssql');
// config for your database
const config = {
user: 'mywindows username',
password: 'my windows password',
server: '(localdb)\\v11.0',
database: 'test',
options: {
encrypt: true
}
};
console.log('starting sql');
var connection = new sql.connect(config, function(err) {
console.log(err);
var request = new sql.Request(connection);
request.query('select * from employees', function(err, recordset) {
if(err) // ... error checks
console.log('Database connection error');
console.dir("User Data: "+recordset);
});
});
sql.close();
console.log('ending sql');
});
app.listen(3002, () => {
console.log('Listening on port 3002');})
Below is the error message
{ ConnectionError: Failed to lookup instance on (localdb) -
getaddrinfo ENOTFOUND (localdb)
at Connection.tedious.once.err (C:\Users\vndbsubramaniam\Desktop\React
projects\ReactWithSql\node_modules\mssql\lib\tedious.js:244:17)
at Object.onceWrapper (events.js:285:13)
at Connection.emit (events.js:197:13)
at InstanceLookup.instanceLookup (C:\Users\vndbsubramaniam\Desktop\React
projects\ReactWithSql\node_modules\tedious\lib\connection.js:945:16)
at sender.execute (C:\Users\vndbsubramaniam\Desktop\React projects\ReactWithSql\node_modules\tedious\lib\instance-lookup.js:66:13)
at GetAddrInfoReqWrap.invokeLookupAll [as callback] (C:\Users\vndbsubramaniam\Desktop\React
projects\ReactWithSql\node_modules\tedious\lib\sender.js:43:16)
at GetAddrInfoReqWrap.onlookupall [as oncomplete] (dns.js:70:17) code: 'EINSTLOOKUP', originalError: { ConnectionError: Failed to
lookup instance on (localdb) - getaddrinfo ENOTFOUND (localdb)
at ConnectionError (C:\Users\vndbsubramaniam\Desktop\React projects\ReactWithSql\node_modules\tedious\lib\errors.js:13:12)
at InstanceLookup.instanceLookup (C:\Users\vndbsubramaniam\Desktop\React
projects\ReactWithSql\node_modules\tedious\lib\connection.js:945:32)
at sender.execute (C:\Users\vndbsubramaniam\Desktop\React projects\ReactWithSql\node_modules\tedious\lib\instance-lookup.js:66:13)
at GetAddrInfoReqWrap.invokeLookupAll [as callback] (C:\Users\vndbsubramaniam\Desktop\React
projects\ReactWithSql\node_modules\tedious\lib\sender.js:43:16)
at GetAddrInfoReqWrap.onlookupall [as oncomplete] (dns.js:70:17)
message:
'Failed to lookup instance on (localdb) - getaddrinfo ENOTFOUND (localdb)',
code: 'EINSTLOOKUP' }, name: 'ConnectionError' } Database connection error
After struggling for hours on this one finally found the answer here SQL to Node connection
It seems i have to add msnodesqlv8 package and use add the driver syntax to the config.
app.get('/test', (req, res) => {
const sql = require('mssql/msnodesqlv8');
// config for your database
const config = {
database: 'test',
server: '(localdb)\\v11.0',
driver: 'msnodesqlv8',
options : {
trustedConnection : true
}
};
console.log('starting sql');
const pool = new sql.ConnectionPool(config);
pool.connect().then(() => {
//simple query
pool.request().query('select * from employees', (err, result) => {
if(err) res.send(err)
else{
return res.json({
data : result.recordset
})
}
})
sql.close();
})
console.log('ending sql');
});
you will need msnodesqlv8 driver, which you have to paste it in require as
var sql = require('mssql/msnodesqlv8'),
as well as you will have to include it in driver section in config object.
var config = {
user:"*****",
password:"*****",
database:"*****",
driver: 'msnodesqlv8',
server:"*****",
options: {
trustedConnection : true
}
}
I am using node.js ssh2 module.I have installed ssh2 module by executing the command 'npm install ssh2'.However, when I use ssh2 to connect to a remote server, it always output the error:
[Error: All configured authentication methods failed] levels: 'client-authentication'
This is my code
var Client = require('ssh2').Client
var conn = new Client();
var option = {
host: '10.171.65.154',
port: 22,
username: 'root',
password: '123456'
};
conn.on('ready', function(){
console.log('Client :: ready');
conn.sftp(function(err, sftp){
if(err) throw err;
sftp.readdir('home', function(err, list){
if(err) throw err;
console.dir(list);
conn.end();
});
});
}).on('error', function(err){
console.log(err);
}).connect(option);
However, I can not connect successfully.I am sure the username and password are correct and I can connect successfully by SecureCRT.
it always output the error:
[Error: All configured authentication methods failed] levels: 'client-authentication'
Probably, you have to handle keyboard-interactive authentication (which is not the same as password). Try something like this:
connection.on('ready', function(){
console.log("Connected!");
}).on('error', function(err){
console.error(err);
}).on('keyboard-interactive', function (name, descr, lang, prompts, finish) {
// For illustration purposes only! It's not safe to do this!
// You can read it from process.stdin or whatever else...
var password = "your_password_here";
return finish([password]);
// And remember, server may trigger this event multiple times
// and for different purposes (not only auth)
}).connect({
host: "your.host.or.ip",
port: 22,
username: "your_login",
tryKeyboard: true
});
I am using Redis and consulting it from nodejs, using the module Redis.
When i exec a client.multi() and the redis server is down the callback doesn't send the error and the nodejs app terminates.
This is the error
/Users/a/db/node_modules/redis/index.js:151
throw callback_err;
^
TypeError: Cannot read property 'length' of undefined
at Command.callback (/Users/a/db/node_modules/redis/index.js:1098:35)
at RedisClient.flush_and_error (/Users/a/db/node_modules/redis/index.js:148:29)
at RedisClient.on_error (/Users/a/db/node_modules/redis/index.js:184:10)
at Socket.<anonymous> (/Users/a/db/node_modules/redis/index.js:95:14)
at Socket.EventEmitter.emit (events.js:95:17)
at net.js:441:14
at process._tickCallback (node.js:415:13)
this is my code:
Constructor class
var redis = require('redis');
var client;
function Redis(){
client = redis.createClient();
client.on("error", function (err) {
console.log("Error " + err);
});
}
Redis.prototype.multi = function(commands,callback){
var err = null;
client.multi(commands).exec(function (error, res) {
if(error){
process.nextTick(function(){
callback(error,null)
})
}else{
process.nextTick(function(){
callback(null,res)
})
}
});
}
FYI, I ran across this in an old lib that depended on old version of node_redis.
This issue was a bug and was fixed in v0.9.1 - November 23, 2013: https://github.com/mranney/node_redis/pull/457
I think that people are still reaching here... (not sure if this answers this specific question directly, but I assume people reaching here since the multi.exec() returns true / the event loop is not waiting for it's response.
After the fixes that went in (in node-redis), it is possible to wrap the result of exec with Promise, and then you will be sure that the result will include the replies from the multi.
So, you can add some redis commands to the multi:
await multi.exists(key);
await multi.sadd(key2,member);
And then in the result do something like:
return new Promise((resolve, reject) => {
multi.exec((err, replies) => {
if (err) {
reject(err);
}
return resolve(replies);
});
});
Otherwise, if you will just do: const reply = await multi.exec();
it will just return you true, and not the replies
** Important to mention - this refers to 'async-redis' and 'node-redis'