DEVGET.NET

Feeding Your Inner Developer

Author: Petronald Green

0

DevOps

How to get Kubernetes CPU allocation for all pods

With the a average person using Kubernetes to deploy workloads it’s likely you’ll hit a CPU allocation wall pretty early. To help debug and optimize your limits, the following lists the cpu requests for each pod.

Credit to abelal83 for the solution.

kubectl get po --all-namespaces -o=jsonpath="{range .items[*]}{.metadata.namespace}:{.metadata.name}{'\n'}{range .spec.containers[*]}  {.name}:{.resources.requests.cpu}{'\n'}{end}{'\n'}{end}"

In my usage however I’ve found the need to also see the not only the cpu requests but memory requests as well as cpu/mem limits. To do so I’ve tweaked the above to be the following

kubectl get po --all-namespaces -o=jsonpath="{range .items[*]}{.metadata.namespace}:{.metadata.name}{'\n'}{range .spec.containers[*]}  {.name}:{'limits.cpu'}:{.resources.limits.cpu}{'\n'}  {.name}:{'limits.memory'}:{.resources.limits.memory}{'\n'}  {.name}:{'requests.cpu'}:{.resources.requests.cpu}{'\n'}  {.name}:{'requests.memory'}:{.resources.requests.memory}{'\n'}{end}{'\n'}{end}"

the output of of the above looks like

(more…)

0

DevOps

Monitor your Kubernetes pod cpu and memory usage 

watch -n 10 "kubectl top pod --all-namespaces | sort -r -k 3 -n"

Breakdown

watch -n 10 – run every 10s
kubectl top pod --all-namespaces – Get the mem and cpu usage of all pods across all namespaces
sort -r -k 3 -n" – Sort in Reverse order on Key 3 and treat as a Number

0

DevOps

How to deploy a container image from Gitlab to AWS Fargate – the important bits

Jumping straight into it. On GitLab I assume you already have your dockerized application and a basic .gitlab-ci.yaml file.

We’re gonna want to build that image and push it to AWS ECR (Amazon Elastic Container Registry). In your gitlab ci file insert the following.

aws-deploy:
  image: docker:latest
  stage: build
  services:
    - docker:dind
  script:
    - apk update && apk -Uuv add python py-pip &&
        pip install awscli && apk --purge -v del py-pip &&
        rm /var/cache/apk/*
    - $(aws ecr get-login --no-include-email --region us-east-1)
    - docker build --pull -t "$AWS_REGISTRY_IMAGE:dev" .
    - docker push "$AWS_REGISTRY_IMAGE:dev"
  only:
    - master

You’re gonna need to set a build-time environment variable called AWS_REGISTRY_IMAGE with the URI of your ECR repository.

Great! We’re halfway there. Do a sample push and verify that your image ends up in ECR

Now we want to deploy to Fargate on every push so… assuming once again you already got your ECS cluster setup. We want to use a CodePipeline to detect pushes & deploy them to ECS.

Under AWS CodePipeline start a new pipeline, Source is Amazon ECR select the appropriate image and tags and stuff. Next

ok here’s the tricky part, to deploy to Fargate we need to add an imagedefinitions.json artifact to our image, this can be done automatically in the build step so.

Build Provider > AWS Codebuild

Create a new project

Environment Image > Managed Image
Operating System > Ubuntu
Runtime > Standard

Down to the Buildspec section, select ‘Insert Build Commands’

Then click ‘Switch to editor and enter the following

version: 0.2

phases:
  install:
    runtime-versions:
       python: 3.8
  post_build:
    commands:
      - printf '[{"name":"my-fargate-container-name","imageUri":"%s"}]' MYAWSID.dkr.ecr.us-east-1.amazonaws.com/MYIMAGENAME:dev > imagedefinitions.json
artifacts:
  files:
    - imagedefinitions.json

Finally Save, continue pipeline creation.. in the Deploy stage select the correct Fargate Cluster/service and DONE.

If you did all of that right, the next time you push to your master branch; it’ll automatically get built and deployed to Fargate!!

1

Development

Angular 8 + Ionic 4 Monorepo Part 1: The Setup

If you’re like me you created this super cool angular web application https://kiwibudget.com/ (shameless promotion) and you users keep asking for a mobile app!

Since your (super cool) frontend is in angular the logical solution is to use Ionic to build the app since you got all this pre-written ng code that you wanna use.

I wont go too deep into the details but after trying to set things up with vanilla Angular workspaces (and failing spectacularly), then trying Angular + nrwl/nx (works but so much hackery to get ionic to work, maintenance would raise technical debt to infinity), I found the gold that is xplat.

This very quickly written post is to document my setup with future blogs as app development progresses.

Disclaimer. This post mostly serves as a note to me of how to set things up, so it’s pretty rough.

Lines that begin with ‘?’ should not be typed and are cli options.

Lets setup our nx workspace

npm init nx-workspace myworkspace
? What to create in the new workspace      empty
? CLI to power the Nx workspace            Angular CLI

npm install -g @nrwl/cli
npm install --save-dev @nstudio/xplat
ng add @nstudio/xplat

Lets make the web app (we call it ‘app’, xplat will prepend ‘web’, change this is you have other requirements)
(You can also configure the prefix but you can look into that yourself)

ng g app
? What name would you like for this app?  app
? What type of app would like to create?  web
? Which frontend framework should it use? angular
? Use xplat supporting architecture?      Yes

? In which directory should the app be generated? 
? Which stylesheet format would you like to use? SASS(.scss)  [ http://sass-lang.com   ]

Lets make the mobile app (we call it ‘app’, xplat will prepend ‘ionic’, change this is you have other requirements)

ng g app
? What name would you like for this app?    app
? What type of app would like to create?    ionic
? Which frontend framework should it use?   angular
? Use xplat supporting architecture?        Yes

We want to use the ionic command to manage our app so lets hook that up.

Create a file ionic.config.json with the following

{
  "name": "ionic-app",
  "integrations": {},
  "type": "angular",
  "root": "apps/ionic-app"
}

We can now run our ionic app with ionic serve --project ionic-app

But wait it still fails…

For some reason capacitor is not installed automatically so since we have setup the ‘ionic’ command we can fix that with

ionic integrations enable capacitor --project ionic-app

Right now you can start apps with

ng serve web-app
ionic serve --project ionic-app

Done!

PS. If you are a lazy dev like me and want to use the Ionic devapp you will also need to install the cordova integration.

It’s not technically a smart idea but… thug life

ionic integrations enable cordova --project ionic-app
0

Linux

NodeFerret – Free Server and Uptime monitoring

Disclaimer
I am the creator of NodeFerret, as a result I will be biased towards it. With that said, let us begin.

So what is NodeFerret?
At a high level NodeFerret aims to be a Linux Server and Uptime monitoring tool. It continuously checks your website(s) and/or server(s) and notifies you (eMail, Slack, Webhook) if anything goes wrong.

You mentioned the word free… much does it really cost?
Well the ‘official’ pricing is on the website https://nodeferret.com/#pricing but for the general hobbyist or indie developer use it’s essentially free.

How can you sustain it while having it ‘essentially free’?
I initially created NodeFerret for myself. To monitor various sites and servers I have online.

After I was done I realized that I had so much extra resources that I could have 1000 more me’s using the service and not have to pay an extra dollar…. so here we are.

Why would I use NodeFerret over say, NewRelic or DataDog?
If you need the level of insight into your servers or applications that these providers provide then NodeFerret probably isn’t right for you.

We are focused on the average developer or sysadmin who wants something easy to use and ‘just works’, Not the DevOps Engineer with a fleet of containers and a full-time job caring for them.

Sounds interesting, where can I sign up?
Right over there –> https://console.nodeferret.com/register

What if I have problems?
You can leave a message on the nodeferret community forum.
Or email me directly at support[@]nodeferret.com

Final Words
I do hope you enjoy using NodeFerret as much as I enjoyed creating it. I am always adding new features and trying to make it a better tool for everyone.