What I learned today

Remote debugging with python and visual studio Code In terminal install debugpy into your environment with something like     python -m pip install debugpy Create a visual studio launch configuration and add following to it following (or just use vs code create configuraiton button to easily create it choose type Python and select from the list, 'Remote attach') { "name" : "Python: Remote Attach" , "type" : "python" , "request" : "attach" , "port" : 5678 , "host" : "localhost" , "pathMappings" : [{ "localRoot" : "${workspaceFolder}" , "remoteRoot" : "." }] }, Run this in the command line to start a debugging server with your script runner python3 -m debugpy --listen 1.2.3.4:5678 --wait-for-client Yourscript.py Now run the launch configuration from vs code to attach to this debugger

This is currently WIP, I will fill in more details but it's a good starting version that is still hopefully useful to the reader... Recently I worked on a project that involved scheduling a number of tasks in parallel in Node.js. Running mutiple tasks I used the await-the library to do this. https://github.com/olono/await-the/blob/master/lib/result.js There are multiple ways to solve this kind of problem. Mainly you have to understand the Node.js is a single threaded environment (See Event loop) and how callbacks operate with a library like async or await-the. Basically, here idea was that you write a function that has a callback as its last argument ```   const doTask = async (arg1, callback) {    const results = await doStuffWith(arg1) ;    callback(results); } ``` Then perform this action on multiple inputs in parallel such as by using the excellent async.mapLimit function if you want to limit how many tasks in parallel you want to to...

This need is incredibly common and useful, and hopefully will save you a lot of time when doing server side calls from your UI application (or even non UI clients like NodeJS applications) Example here is to send a POST request to an endoint /api/item/new (which will create a new item in the database). We will just assume tbhe backend is already setup (it's not relevant to this article). All we need to know is that we can do a POST /api/item/new and send it form data with two pieces of info     name, filter So, if you have a node.js application (I was using Vue-cli generated project, but it does not matter), install 'axios' (a most popular tool to make server calls these days) npm i axios --save OR yarn add axios (my preferred method) Now, in your service JS file (which is generally when I keep all my api calls) do something like this createNew ( name , filter ) { let formData = new FormData (); formData . append ( "name" , ...

My current recipe which works not bad is setup spring at localhost:8082, vue-cli app on localhost:8080 setup proxy in devServer for webpack to point all /api calls to localhost:8082. So now any calls made from vue application to /api will be sent to the spring application at /api setup spring api endpoints at /api add a 'buildx' npm task to do the usual "vue-cli build && copy " over to spring src/main/resources/static area, mine usually looks like this in package.json "buildx" : "vue-cli-service build && copyfiles -u 1 dist/* dist/**/* ../build/resources/main/public && copyfiles -u 1 dist/* dist/**/* ../src/main/resources/public -V" ,   I usually copy to both build/ and src area, since build makes restart instantliy work in spring side, and src/ area makes bundle available in spring jar file created using bootJar task, for deployment setup devtools on spring to autorestart I can dev/test using jus...

Authenticating against an Active Directory setup is quite common in organizations using Spring Boot / Spring Security can be a pain if you don't know exactly the requirements. I needed to add auth in my web app and secure some but not all endpoints of the application. My story was, I needed Spring security to authenticate against my company LDAP server which uses Active Directory I started by using the standard LDAP guide such as this which are all over the Internet, https://spring.io/guides/gs/authenticating-ldap/ and was able to setup the basic framework However, only test level LDAP auth was working for me, when I tried to auth against the company LDAP secure server, I had to resolve a few issues After 1 week and working with several devs at the company, I finally found why it was not working and the fix was easy Since I spent a week or so resolving this, I wanted to write this up in case someone finds this useful. Here is what I did (it was easy until the fourth ...

If you have Spring controller that uses repository objects, it can become a bit messy to write tests with mocks that have to mock various repository object methods like save() etc. Instead, you can use Here is an example controller that uses repository objects: @RestController public class StateManagerController { public StateManagerController(XRepository aRepository, YRespository yRepo) {   } public void aMethod() { // use xRepo, yRepo : e.g., xRepo.save() , yRepo.delete() etc. } ... } To test methods of this controller that use the repository objects, you will likely have to mock each repository collaborator object. Then you can get into lots of mocking details that make your tests ugly. Instead, I find that using the following pattern greatly simplifies both your code and tests. It's very simple but works great. 1. In your controller, only inject/depend on @Service objects. Don't use repository objects directly 2. Test your con...

Intro Spring boot offers a wonderful module called the actuator. It is somewhat similar to the tools offered by Rails or other frameworks to get a better view of your application. Basically when you enable it, you can browse to a url which by default is at /actuator (but can be configured), where you will find very interesting pieces of information about your Spring boot application. For example, if you built a MVC webapp where you wrote a number of @Controller or @RestController classes, then going to /actuator/mappings will list your endpoints along with which controller method serve which endpoint etc. But there is a whole lot more in actuator you will find useful. In this article, I will show you how to use it in your application, and also how to only enable it in your development profile. I would assume that you don't want soething like this enabled in your production deployment. We will use Spring profiles for this. Setup I am assuming you have a working Spri...