I’d like to keep track of API requests that I make with react-redux. To do this I’d like to generate a request Id inside the action and pass that along to middleware and reducers through the payload. Then when I’m dispatching the action from my component I can capture the request Id and use …
Tag: design-patterns
Repository pattern practical use cases and implementation in node.js
Can someone please explain what’s the use of this pattern with example? All I’m confused is that I can have database instance wherever I want and I have flexibility to do anything by it, am I wrong? specially is Answer The repository pattern is a strategy for abstracting data access. it’s like putting a…
How to design a proactive monitoring system?
This is a vague question on design. I have microservice which performs order management. The service orchestrates every order from Placed to Delivered. A lot of things happening in between. Let say these are statuses an order can be. Placed Authorized Shipped Delivered I have an elastic search dashboard which…
d3js mask to show dots over bar chart
i saw this example here: https://jsfiddle.net/gruc1vod/4/ and i want to add these dots over my bar chart using mask. Here is my JavaScript code: Here is my CSS code: and here my live example: https://jsfiddle.net/uao5yfhm/6/ Where is the problem and i cannot see this outcome correct outcome but i see this one…
toggling variable inside Module Pattern using function declaration vs function expression
I have a module pattern with a variable setting the currentPlayer to 1. I use a function expression to toggle that variable If I run game.currentPlayer it logs 1, I then run game.toggleCurrentPlayer(), and it doesn’t change currentPlayer as intended, it still returns 1. However, changing the toggleCurre…
Rxjs nested subscribe with multiple inner subscriptions
Original promise based code I’m trying to rewrite: I’m trying to figure a way how to avoid the nested subscriptions anti-pattern in the following scenario: What would be the correct ‘RxJS way’ to do this? Answer That seems pretty strange to me. You’re creating new subscription fo…
how does reactor pattern work in Node.js?
I am reading Node.js Design Patterns. I am stuck in the understanding of the reactor pattern. I do not see any call stack here. I thought the call stack was one of the main parts of Node.js design. Can anyone please help me understand this diagram? Also, there is no callback queue. Answer Everything starts wi…
Function in JavaScript that can be called only once
I need to create a function which can be executed only once, in each time after the first it won’t be executed. I know from C++ and Java about static variables that can do the work but I would like to know if there is a more elegant way to do this? Answer If by “won’t be executed” you …