bluebird | full featured promise library with unmatched performance | Reactive Programming library

i know this probably has been asked before, but coming from single-threaded language for the past 20 years, i am really struggling to grasp the true nature of node. believe me, i have read a bunch of SO posts, github discussions, and articles about this.

i think i understand that each function has it's own thread type of deal. however, there are some cases where i want my code to be fully synchronous (fire one function after the other).

for example, i made 3 functions which seem to show me how node's async i/o works:

I have the following serverless yaml that I'm using to try to deploy my first step function:

I have upgraded my angular to angular 13. when I run to build SSR it gives me following error.

I entered the command npm install -D tailwind css postcss autoprefixer vite in VS-Code.

My environment is:

• NPM version: 8.1.2
• Node.js version: 16.13.1

Which resulted in following warning:

I'm developing an api using strapi 3.6 that I develop without docker locally and I run with docker in production.

Locally, an endpoint that returns a 400 will become a 500 in production.

I have been investigating the issue and when I run docker locally, I also get a 500 instead of a 400.

I couldn't find any relevant resources, does someone have any clue why this could happen?

EDIT

The backend is deployed on AWS Elastic Beanstalk.

What I tried:

• ❌ requesting the load balancer directly
• ❌ requesting the underlying ec2 directly
• ❌ running docker locally in production mode
• ❌ running docker locally in dev mode
• ✅ building strapi and running the server like docker does but without docker

All above cases gave me a 500 instead of the expected 400, except for the last case that returned a 400 as expected.

The error displayed in the logs are the ones expected. Only the way the error is returned by the api changes.

Here is the code of the middleware that handles errors globally:

I was following this video and when I try to create a react application on my system by using the following command

TL;DR: Vertical or Horizontal scaling for this system design?

I have NGINX running as a load balancer for my application. It distributes across 4 EC2 (t2.micro's cuz I'm cheap) to route traffic and those are all currently hitting one server for my MySQL database (also a t2.micro, totalling 6 separate EC2 instances for the whole system).

I thinking about horizontally scale my database via Source/Replica distribution, and my thought is that I should route all read queries/GET requests (the highest traffic volume I'll get) to the Replicas and all write queries/POST requests to the Source db.

I know that I'll have to programmatically choose which DB my servers point to based on request method, but I'm unsure of how best to approach that or if I'm better off vertically scaling my DB at that point and investing in a larger EC2 instance.

Currently I'm connecting to the Source DB using an express server and it's handling everything. I haven't implemented the Source/Replica configuration just yet because I want to get my server-side planned out first.

Here's the current static connection setup:

dev configuring db in development mode connecting to -> NaN Unhandled rejection MongooseError: The uri parameter to openUri() must be a string, got "number". Make sure the first parameter to mongoose.connect() or mongoose.createConnection() is a string. at NativeConnection.Connection.openUri (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\connection.js:694:11) at E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\index.js:351:10 at E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\helpers\promiseOrCallback.js:32:5 at Promise._execute (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\bluebird\js\release\debuggability.js:384:9) at Promise._resolveFromExecutor (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\bluebird\js\release\promise.js:518:18) at new Promise (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\bluebird\js\release\promise.js:103:10) at promiseOrCallback (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\helpers\promiseOrCallback.js:31:10) at Mongoose._promiseOrCallback (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\index.js:1149:10) at Mongoose.connect (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\node_modules\mongoose\lib\index.js:350:20) at Object.connectDb [as dbConfig] (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\lib\config\dbConfig.js:28:14) at Object. (E:\reacttut\reactdemo\eSponsors-master\eSponsors-master\server.js:21:8) at Module._compile (node:internal/modules/cjs/loader:1101:14) at Object.Module._extensions..js (node:internal/modules/cjs/loader:1153:10) at Module.load (node:internal/modules/cjs/loader:981:32) at Function.Module._load (node:internal/modules/cjs/loader:822:12) at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12) at node:internal/main/run_main_module:17:47

[nodemon] clean exit - waiting for changes before restart