net.Stream is not a constructor - Node Postgres

Question

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.

Your `pg-promise` usage is incorrect. Instead of `var pgp = require('pg-promise');` there must be `var pgp = require('pg-promise')(/*initialization options*/);`, as per the documentation. — vitaly-t, Feb 02 '17 at 08:43
@vitaly-t, thank you for responding. I'm using Browserify to define `require()` in my application, and when I add the second set of parameters - `var pgp = require('pg-promise')();` as in the documentation, I get `require(...) is not a function`. Should I be using something besides Browserify? — Megan McPherson, Feb 02 '17 at 18:47
`pg-promise` is strictly a server-side module, why on earth would you ever need to use Browserify on it? :) — vitaly-t, Feb 02 '17 at 20:05

Rein · Answer 1 · 2017-02-10T01:22:14.957

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)

net.Stream is not a constructor - Node Postgres

1 Answers1