How to Save sed Output Directly to a File
You have 3 options here:
I needed this when doing bulk find-and-replace across config files in a deployment script. The -i option is the most common …
Technical Articles
In-depth guides, insights, and best practices for modern software engineering
How to Convert BigNumber to Int/Number in Ethers/Web3
If you have a BigNumber when using web3, then you can convert this to a regular Javascript Number using the ethers library as follows: …
How to Create a Pyramid Array in Javascript
The challenge
Write a function that when given a number >= 0, returns an Array of ascending length subarrays.
pyramid(0) => [ ]
pyramid(1) => …How to Create a Reverse Polish Notation Calculator in Javascript
The challenge
Your job is to create a calculator which evaluates expressions in Reverse Polish notation.
For example expression 5 1 2 + 4 * + 3 - …
How to declare a global variable in React?
If you need to declare a global variable in React, then you can do the following:
Create a file called config.js
module.exports = global.config = { …How to Find the Missing Term in an Arithmetic Progression in Javascript
The challenge
An Arithmetic Progression is defined as one in which there is a constant difference between the consecutive terms of a given series of …
Read Article →How to Count Characters in a Javascript String
The challenge
The main idea is to count all the occurring characters in a string. If you have a string like aba, then the result should be {'a': 2, …
How to Increment/Decrement a value in React/NextJS
Use the following code block to get started:
function GetCount() {
const [count, setCount] = useState(1);
const incrementCounter = () => { …How to disable text selection highlighting in CSS
If you would like to disable the text selection highlighting that is enabled by default on all browsers, then you can do this:
user-select: none;
If …
Read Article →Irreducible Sum of Rationals in Golang
The challenge
You will have a list of rationals in the form:
lst = [ [numer_1, denom_1] , ... , [numer_n, denom_n] ]
where all numbers are positive …
Read Article →How to copy S3 objects between AWS accounts
In your source account create a customer-managed policy:
{
"Version": "2012-10-17",
"Statement": [
{ …How to find all symlinks in a directory tree on Mac
If you need to recursively find all symbolic links in a directory tree on a Mac, then you have a couple of options.
You could be trying to find them …
Read Article →How to Install App Mesh on AWS EKS
You can follow the steps below to install App Mesh on AWS EKS (Kubernetes).
Step 1 – Prerequisites
curl -o pre_upgrade_check.sh …[Solved] Kubernetes Namespace stuck in Terminating state
If you have tried to delete a Kubernetes namespace, and it has been hanging in ‘deleting’ for hours on end, it’s likely that you have …
Read Article →[Solved] Error creating: pods “my-service-a-xxx” is forbidden: error looking up service account my-apps/my-service-a: serviceaccount “my-service-a” not found
So you’ve run a deployment and tried to check the pods and there’s nothing there!
kubectl get pods
Next step is to see what’s …
Read Article →[Solved] error: src refspec main does not match any
If you get the following error:
error: src refspec main does not match any
error: failed to push some refs to 'https://github.com/ao/xxx.git' …How to Force a Redeploy in Kubernetes
If you need to force a redeploy of a deployment in Kubernetes, then you can use the rollout feature.
You may have an image that has been updated, but …
Read Article →How to Print to stdout in Flask using Python
If you are trying to print() to the console/stdout in your Flask app, but nothing is happening, then you just need to flush your prints, as follows: …
How to Restart a Deployment in Kubernetes
If you need to restart a deployment in Kubernetes, perhaps because you would like to force a cycle of pods, then you can do the following:
Step 1 – …
Read Article →How to push multiple Dockerfile apps to AWS ECR at the same time
I have a parent directory containing multiple sub-directories. Each of these child directories is a different application and contains a Dockerfile.
I …
Read Article →How to Create a Horizontal Pod Autoscaler in Kubernetes
If you could like to a create a Horizontal Pod Autoscaler (hpa) in Kubernetes, then you could run the following:
Step 1 – Create a Deployment
If you …
Read Article →How to Run a Load Generator on Kubernetes
If you would like to test hpa, Horizontal Pod Autoscaling, or throw some chaos at a specific deployment in Kubernetes, then you could run a Load …
How to Deploy a Metrics Server in Kubernetes
If you would like to deploy a Metrics Server in Kubernetes, then you first need to create a namespace for it to live it, followed by installing the …
Read Article →How to create an AWS EKS cluster using eksctl
eksctl dramatically simplifies the creation of AWS EKS clusters, by providing a simple command-line interface.
Step 1 – Define a Cluster YAML
You can …
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