I am using Promised-Mongo to connect MongoDB with Promises from NodeJS backend code. It worked fine, until I enabled MongoDB's client access control. When I run this code, I get "could not authenticate" message":
var pmongo = require('promised-mongo').compatible();
var db = pmongo('myusername:mypassword#localhost/mydb', ['candidates']);
db.candidates.save(req.body)
.then(function () {
// never reached here
})
.catch(function (e) {
// it reached here, where e.message says "could not authenticate"
});
Pure MongoDB code (i.e. no Promises...) works fine:
var mongodb = require('mongodb');
var uri = 'mongodb://myusername:mypassword#localhost/mydb';
mongodb.MongoClient.connect(uri, function (err, db) {
if (err) {
// never reached here
}
var candidates = db.collection('candidates');
candidates.insert(req.body, function(err, result) {
if (err) {
// never reached here
}
res.send('{result: success}');
});
});
Any idea?
Per several issues in the github repository (see here and here) it looks like using this library with authentication is totally broken. Per the second link, most people seem to be wrapping the official library with a promise via something like promisify, bluebird, or a thin custom wrapper.
Related
I searched for a good example of Node+Express+Oracle. I need to read values from an Oracle view to create the response to a GET operation.
Most examples does not use "Express" (my choice of framework) and simply log the database information. Here are some of the best I found : from Express, from Oracle 1, from Oracle 2
Here is the one I preferred to base my code on. I like it because it includes Express, and actual manipulation of the response data. Sadly, it still does not work for me. And I am wondering what the issue is.
I think I understand the asynchronous nature of the JavaScript language (ie: callbacks), and I am beginning to suspect my problem might be tied to : A stupid variable name snafu, My version of Oracle (12c) or the fact that the source is a view (replicated from another schema).
I tried the following code in many other forms (including async functions), and also tried to switch from node 10 to 11... no changes.
Any help would be welcomed.
As of now, the code "works", in the sense that the row data from the database is printed on screen, but the response in Postman (my test tool) is empty, with no http error code... just like the connection would have been cut before replying.
Note the commented, misplaced response code, that returns a response if uncommented (and then crashes the program since the header is written twice).
Here is the code.
It is based on this project/file (and simplifed):
var express = require('express');
var oracledb = require('oracledb');
var app = express();
var connAttrs = {
"user": "user",
"password": "pass",
"connectString": "some_host/SCHEMANAME"
}
// Http Method: GET
// URI : /myObj
app.get('/myObj', function (req, res) {
"use strict";
oracledb.getConnection(connAttrs, function (err, connection) {
if (err) {
// Error connecting to DB
res.set('Content-Type', 'application/json');
res.status(500).send(JSON.stringify({
status: 500,
message: "Error connecting to DB",
detailed_message: err.message
}));
return;
}
// THIS works if uncommented. This is obviously the wrong place to put this.
//res.contentType('application/json').status(200);
//res.send("Test.1.2");
connection.execute("SELECT * FROM SCHEMA.SOMEVIEW", {}, {
outFormat: oracledb.OBJECT // Return the result as Object
}, function (err, result) {
if (err) {
res.set('Content-Type', 'application/json');
res.status(500).send(JSON.stringify({
status: 500,
message: "Error getting the user profile",
detailed_message: err.message
}));
} else {
//log first row... THIS WORKS !
console.log(result.rows[0]);
//This does not work, like if "res" could not be touched here !!!
res.contentType('application/json').status(200);
res.send(JSON.stringify(result.rows[0]));
}
// Release the connection
connection.release(
function (err) {
if (err) {
console.error(err.message);
} else {
console.log("GET /myObj: Connection released");
}
});
});
});
});
var server = app.listen(3000, function () {
"use strict";
var host = server.address().address,
port = server.address().port;
console.log(' Server is listening at http://%s:%s', host, port);
});
Here is a representation of the console:
{ field1: 'some data',
field2: 'some more data' }
GET /myObj : Connection released
And here is the behaviour in postman:
ARGGG ! It was a simple timeout ! Postman DOES mention it as a possibility (see image), but I would like the program to make it flash it bright letters !!!
Closing the question. Sorry for the disturbance.
First of all, this is one of my first projects in Node.js so I'm very new to it.
I have a project I want to make that is a SOAP (I know, SOAP... backwards compatibility, huh?) interface that connects to an Oracle database.
So I have a WSDL describing what these functions look like (validation for addresses and stuff) and I have a connection to the database.
Now when using the SOAP npm module, you need to create a server and listen using a service that allows you to respond to requests. I have a separate file that contains my SOAP service but this service should do queries on the database to get its results.
How would I go about sort of 'injecting' my database service into my SOAP service so that whenever a SOAP call is done, it orchestrates this to the correct method in my database service?
This is what my code looks like:
databaseconnection.js
var oracledb = require('oracledb');
var dbConfig = require('../../config/development');
var setup = exports.setup = (callback) => {
oracledb.createPool (
{
user : dbConfig.user,
password : dbConfig.password,
connectString : dbConfig.connectString
},
function(err, pool)
{
if (err) { console.error(err.message); return; }
pool.getConnection (
function(err, connection)
{
if (err) {
console.error(err.message);
return callback(null);
}
return callback(connection);
}
);
}
);
};
databaseservice.js
var DatabaseService = function (connection) {
this.database = connection;
};
function doSomething(callback) {
if (!this.database) { console.log('Database not available.'); return; }
this.database.execute('SELECT * FROM HELP', function(err, result) {
callback(result);
});
};
module.exports = {
DatabaseService: DatabaseService,
doSomething: doSomething
};
soapservice.js
var myService = {
CVService: {
CVServicePort: {
countryvalidation: function (args, cb, soapHeader) {
console.log('Validating Country');
cb({
name: args
});
}
}
}
};
server.js
app.use(bodyParser.raw({type: function(){return true;}, limit: '5mb'}));
app.listen(8001, function(){
databaseconnection.setup((callback) => {
var temp = databaseservice.DatabaseService(callback);
soapservice.Init(temp);
var server = soap.listen(app, '/soapapi/*', soapservice.myService, xml);
databaseservice.doSomething((result) => {
console.log(result.rows.length, ' results.');
});
});
console.log('Server started');
});
How would I go about adding the databaseservice.doSomething() to the countryvalidation soap method instead of 'name: args'?
Also: I feel like the structure of my code is very, very messy. I tried finding some good examples on how to structure the code online but as for services and database connections + combining them, I didn't find much. Any comments on this structure are very welcome. I'm here to learn, after all.
Thank you
Dieter
The first thing I see that looks a little off is the databaseconnection.js. It should be creating the pool, but that's it. Generally speaking, a connection should be obtained from the pool when a request comes in and release when you're done using it to service that request.
Have a look at this post: https://jsao.io/2015/02/real-time-data-with-node-js-socket-io-and-oracle-database/ There are some sample apps you could have a look at that might help. Between the two demos, the "employees-cqn-demo" app is better organized.
Keep in mind that the post is a little dated now, we've made enhancements to the driver that make it easier to use now. It's on my list to do a post on how to build a RESTful API with Node.js and Oracle Database but I haven't had a chance to do it yet.
I'm working with mongojs and writing tests for mocha running coverage with istanbul. My issue is that I would like to include testing db errors.
var mongojs = require('mongojs');
var db = mongojs.connect(/* connection string */);
var collection = db.collection('test');
...
rpc.register('calendar.create', function(/*... */) {
collection.update({...}, {...}, function (err, data) {
if (err) {
// this code should be tested
return;
}
// all is good, this is usually covered
});
});
the test looks like this
it("should gracefully fail", function (done) {
/* trigger db error by some means here */
invoke("calendar.create", function (err, data) {
if (err) {
// check that the error is what we expect
return done();
}
done(new Error('No expected error in db command.'));
});
});
There is a fairly complex setup script that sets up the integration testing environment. The current solution is to disconnect the database using db.close() and run the test resulting in an error as wanted. The problem with this solution arises when all the other tests after that require the database connection fail, as I try to reconnect without success.
Any ideas on how to solve this neatly? Preferably without writing custom errors that might not be raised by next version of mongojs. Or is there a better way of structuring the tests?
What about mocking the library that deals with mongo?
For example, assuming db.update is eventually the function that gets called by collection.update you might want to do something like
describe('error handling', function() {
beforeEach(function() {
sinon.stub(db, 'update').yields('error');
});
afterEach(function() {
// db.update will just error for the scope of this test
db.update.restore();
});
it('is handled correctly', function() {
// 1) call your function
// 2) expect that the error is logged, dealt with or
// whatever is appropriate for your domain here
});
});
I've used Sinon which is
Standalone test spies, stubs and mocks for JavaScript. No dependencies, works with any unit testing framework.
Does this make sense?
I'm using node js, express and postgresql as backend.
This is the approach I used to make a rest API:
exports.schema = function (inputs, res) {
var query = knex('schema')
.orderBy('sch_title', 'asc')
.select();
query.exec(function (err, schemas) {
if(err){
var response = {
message: 'Something went wrong when trying to fetch schemas',
thrownErr: err
};
console.error(response);
res.send(500, response);
}
if(schemas.length === 0){
var message = 'No schemas was found';
console.error(message);
res.send(400, message);
return;
}
res.send(200, schemas);
});
};
It works but after a while postgres logs an error and it's no longer working:
sorry, too man clients already
Do I need a close each request somehow? Could not find any about this in the express docs. What can be wrong?
This error only occurs on production server. Not on developing machine.
Update
The app only brakes in one 'module'. The rest of the app works fine. So it's only some queries that gives the error.
Just keep one connection open for your whole app. The docs shows an example how to do this.
This code goes in your app.js...
var Knex = require('knex');
Knex.knex = Knex.initialize({
client: 'pg',
connection: {
// your connection config
}
});
And when you want to query in your controllers/middlewares...
var knex = require('knex').knex;
exports.schema = function (req, res) {
var query = knex('schema')
.orderBy('sch_title', 'asc')
.select();
// more code...
};
If you place Knex.initialize inside an app.use or app.VERB, it gets called repeatedly for each request thus you'll end up connecting to PG multiple times.
For most cases, you don't need to do an open+query+close for every HTTP request.
I am new to Angular JS and node.js/express framework. I am working on a small application which uses angular and express frameworks. I have express app running with couple of end points. One for POST action and one for GET action. I am using node-mysql module to store and fetch from mysql database.
This application is running on my laptop.
angular.js client:
controller
function ItemController($scope, storageService) {
$scope.savedItems = storageService.savedItems();
alert($scope.savedItems);
}
service
myApp.service('storageService', function($resource) {
var Item = $resource('http://localhost\\:3000/item/:id',
{
id:'#id',
},
{
query: {
method: 'GET',
isArray: true
}
);
this.savedItems = function() {
Item.query(function(data){
//alert(data);
return data;
});
}
Express server with mysql database:
...
app.get('/item', item.list);
...
items.js
---------
exports.list = function(req, res) {
var sql = 'select * from item';
connect: function() {
var mysql = require('mysql');
var connection = mysql.createConnection({
host : 'localhost',
user : 'admin',
database : 'test'
});
return connection;
},
query: function(sql) {
var connection = this.connect();
return connection.query(sql, function(err, results) {
if (err) throw err;
return results;
});
},
res.send(results);
};
When I send static array of items (json) from server, $scope.savedItems() is getting populated.
but when I access items in database, even though server is returning items, $scope.savedItems in client is empty. Using $http directly did not help either.
I read async nature of $resource and $http from angular.js documentation and I am still missing something or doing something wrong.
Thanks in advance and appreciate your help.
This has to do with the async nature of angular $resource.
$scope.savedItems = storageService.savedItems();
Returns immediately an empty array, which is populated after the data returns. Your alert($scope.savedItems); will therefore show only an empty array. If you look at your $scope.savedItems a little bit later you would see that it has been populated. If you would like to use the data just after it has been returned you can use a callback:
$scope.savedItems = storageService.savedItems(function(result) {alert(result); });
Just as a quick note. You could also watch the savedItems.
function ItemController($scope, storageService) {
$scope.savedItems = storageService.savedItems();
$scope.$watch(function() {
return $scope.savedItems;
}, function(newValue, oldValue) {
if (typeof newValue !== 'undefined') {
// Do something cool
}
},
true);
}
i suspect, node is not returning mysql results. The fact that it works for static files and not for mysql rules out issues with angular. Can you add firebug logs for the http call or chrome developer logs. This can shed more light on the matter