how to connect heroku postgres database in nodejs - node.js

Question

I have created an app on heroku server and installed Postgres free add-on. Now I have a nodejs project in which I am connecting this database using pg modules. So for this I have created
db-connect.js
var { Pool } = require('pg');
var nodeEnvFile = require("node-env-file");
nodeEnvFile(".env");
var config = {
user: process.env.DB_USER,
host: process.env.DB_IP,
database: process.env.DB,
password: process.env.DB_PASSWORD,
port: process.env.DB_PORT,
max: 10, // max number of connection can be open to database
idleTimeoutMillis: 30000, // how long a client is allowed to remain idle before being closed
};
var pool = new Pool(config);
module.exports = {
query: (query, callback) => {
console.log(query);
pool.connect().then(client => {
return client.query()
.then((result) => {
client.release();
console.log(result.rows)
callback(null, result.rows[0]);
})
.catch(err => {
client.release();
callback(err, null);
});
})
}
}
and then in the API layer, I have imported this file
const db = require("../db/db-connect");
and used like this
router.get("/getdata/", (req, res) => {
var query = "query";
db.query(query, (err, result) => {
if (err) {
res.status(400).send(err);
}
res.send(result);
})
});
and this was showing following error
(node:1984) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): error: no pg_hba.conf entry for host "157.39.161.5", user "ltolmhjmwnfokl", database "den55ln368anf8", SSL off
(node:1984) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
select * from get_notifications('sidhu',0,1);
(node:1984) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 2): error: no pg_hba.conf entry for host "157.39.161.5", user "ltolmhjmwnfokl", database "den55ln368anf8", SSL off
and then I enabled ssl option in the config object
var config = {
user: process.env.DB_USER,
host: process.env.DB_IP,
database: process.env.DB,
password: process.env.DB_PASSWORD,
port: process.env.DB_PORT,
max: 10, // max number of connection can be open to database
idleTimeoutMillis: 30000, // how long a client is allowed to remain idle before being closed
ssl: true
};
but now this is showing
(node:252) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'submit' of undefined
(node:252) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
ServiceUnavailableError: Response timeout
at IncomingMessage.<anonymous> (D:\PROJECTS\PuWifi\GitHubForHeroKu\PuWifi\node_modules\connect-timeout\index.js:84:8)
at emitOne (events.js:116:13)
at IncomingMessage.emit (events.js:211:7)
at Timeout._onTimeout (D:\PROJECTS\PuWifi\GitHubForHeroKu\PuWifi\node_modules\connect-timeout\index.js:49:11)
at ontimeout (timers.js:475:11)
at tryOnTimeout (timers.js:310:5)
at Timer.listOnTimeout (timers.js:270:5)
what is the issue? Am I missing something?

Answer 1

Actually, I was missing to pass the query in client.query(). It should be client.query(query). Here is the code
module.exports = {
query: (query, callback) => {
console.log(query);
pool.connect().then(client => {
return client.query()
.then((result) => {
client.release();
console.log(result.rows)
callback(null, result.rows[0]);
})
.catch(err => {
client.release();
callback(err, null);
});
})
}
}
The other is to use pool.query
module.exports = {
query: (query, callback) => {
console.log(query);
pool.query(query).then(response => {
callback(null, response.rows);
}).catch(err => {
callback(err, null);
})
}
}
For detail: https://github.com/brianc/node-postgres/issues/1597#issuecomment-375554709