i have very good js background but i am new to node.js
i dont undersand why simple class object function is not calling
function functions () {
function test () {
console.log("function ok");
function test2 () {
console.log("function inside function is ok");
}
return {
test2 : test2
};
}
return {
test : test
};
}
var test_function = new functions();
functions.test.test2();
i get error
TypeError: Cannot read property 'test2' of undefined
thanks
Try calling test_function.test().test2(). You need to invoke test() before you can invoke test2(). Also, in your example you correctly invoked functions() and assigned it to test_function, but then you did not do anything with it.
Call it like this:
var test_function = new functions();
test_function.test().test2();
Related
I am stuck on this for few days now.
while testing my handler function I would like to "fake" the call to rotateApiKeys fonction I was thinking to use stubs to achieve that.
But first I would like to see if at least I could spy on rotateApiKeys while calling the handler, so far I am getting:
AssertError: expected rotateApiKeys to be called once but was called 0 times and I can see that function actually been called.
Questions:
What would you recommend me to use? Mock/Stub/Spy
If Spy should work, why I am getting that assertError?
Handler:
async function handler(event) {
// declare a new JSON object
let handlerObject = {
"event": event,
"isValidEvent": rotateFunctions.validateEvent(event),
"actionCountObject": {}
};
if (handlerObject.isValidEvent) {
// continue here
handlerObject.actionCountObject = await rotateApiKeys(event);
}
// console log JSON handlerObject
console.log("handlerObject: " + JSON.stringify(handlerObject));
// return the object
return handlerObject;
}
unit test code:
it("Should call rotate", async function() {
var rotate = sinon.spy(rotateApiKeys, 'rotateApiKeys');
const result = await rotateApiKeys.handler(event);
rotate.restore();
sinon.assert.calledOnce(rotate);
});
I'm under the impression that jest.spyOn.mockImplementationOnce can mock a function as long as it is implemented as a function expression, but might fail to mock when the function is written as a function declaration. Why is it behaving like that?
I have one TS file in the folder */this_works with the following code:
export function myFunction() {
return myOtherFunction();
}
export const myOtherFunction = function() {
return 'something';
};
And then another TS file in the folder */this_doesnt with the following code:
export function myFunction() {
return myOtherFunction();
}
export function myOtherFunction() {
return 'something';
}
The only difference between them is that myOtherFunction is either a function declaration or a function expression.
Both files are submitted to the same test with jest.
import * as myModule from '../index';
describe('myFunction', () => {
it('does something', () => {
jest
.spyOn(myModule, 'myOtherFunction')
.mockImplementationOnce(
function() {
return 'hello jest';
},
);
const result = myModule.myFunction();
expect(result).toEqual('hello jest');
});
});
All code can be found at my playground repo's folder
The result is that the function expression is mocked and the test passes, while the function declaration is not mocked and the test fails.
Anecdotally, this seems to only happen if the function being mocked is not being called directly, instead it is being called by another function. When the declared function gets called directly, the test passes.
I would like to understand why that is so I can write better tests.
I'm using a node-schedule for schedule a synchronizeAll() method. I'm trying this
constructor() {
var schedule = require('node-schedule');
var rule = new schedule.RecurrenceRule();
rule.minute = new schedule.Range(0, 59, 5);
this.initializeDb().then(() => {
schedule.scheduleJob(rule, function () {
console.log('works!!');
this.synchronizeAll();
});
});
}
synchronizeAll() {
let synchronizeProjects: SynchronizeProjects;
synchronizeProjects.synchronize().then(result => {
console.log(result);
});
}
This project results in
works!!
/home/braulio/projetos/github/redtench/src/node/dist/redmine/redmine.js:14
this.synchronizeAll();
^
TypeError: this.synchronizeAll is not a function
I know the problem occurs because I am calling the class method within the calback function, however I do not know how to correct
The this keyword is losing the original reference inside of the callback function for scheduleJob. You can either store this in a variable (let t = this) prior to the this.initialiseDB() call, then do t.synchronizeAll(), or you can keep your this reference by using an arrow function like below.
schedule.scheduleJob(rule , () => { this.synchronizeAll(); }
Ive node moudle which i need to export two functions and get to both of the function a parameter arg1,I try with the following I got error,what am I doing wrong here ?
UPDATE
Ive two method inside module
1. I need to expose it outside and to call it explicit from other
module with parameter
like
require('./controller/module')(functionName1)(parameter);
another function(functionName2) in this module which I need to call it explicit with two parameter ,how should I do it right?
It is not very clear what you want to do, but i think you want something like that:
module.exports = function (arg1) {
return {
server: function (params1) {
//do something with arg1 and params1
},
proc: function (params2) {
//do something with arg1 and params2
}
}
};
And using the module:
var arg1 = 'whatever'
var myMod = require('myMod')(arg1);
myMod.server();
myMod.proc();
Option 2
If i look at your new example
require('./controller/module')(functionName1)(parameter);
you need module that exports a function that returns another function (Higher Order Function).
So for example:
module.exports = function(functionName1) {
if(functionName1 === 'server'){
return function server(parameter){
//do your stuff here
}
}
if(functionName1 === 'proc'){
return function proc(parameter){
//do your stuff here
}
}
};
i have a question regarding defining objects in modules.
lets say i have a module:
/*---obj----*/
function A (param){
this.parm=param;
function func(){
//do somthing
}
}
exports.func=func;
/*---file.js----*/
obj=require('obj');
function fileFunc(A){
A.func();//with out this line it works fine
A.param=2;
}
}
for some reason it does not recognize the function in the object A. it recognizes the object A and its different vars, but when it comes to executing the function it gives the msg:
TypeError: Object # has no method 'func'
i tried also to export the function in A by:
exports.A.func=A.func
or
exports.func=func
neither works..
does someone have a clue?
thanx
matti
The function you defined inside of A is local only to that function. What you want is
function A(param) {
this.param = param;
}
A.func = function() {
// do something
};
But if you are treating A as a constructor then you'll want to put that function in A's prototype
A.prototype.func = function() {
// do something
};