Vineel Sai Blog

Install Portainer in docker Linux

mail@vineelsai.com (Vineel Sai) — Wed, 04 Jan 2023 12:00:00 +0000

Portainer hides the complexity of managing containers behind an easy-to-use UI. By removing the need to use the CLI, write YAML or understand manifests, Portainer makes deploying apps and troubleshooting problems so easy that anyone can do it.

Prerequisites

Docker

If you haven’t installed docker follow this article and install docker

Install Portainer

Create docker volume for portainer

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docker volume create portainer_data

Run the following command to download and run the portainer docker container.

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docker run -d -p 8000:8000 -p 9443:9443 --name portainer --restart=always -v /var/run/docker.sock:/var/run/docker.sock -v portainer_data:/data portainer/portainer-ce:latest

Now go to https:meachine-ip:9443 and click advanced procied to unsafe and you get to auth page and create a password and click on create user.

Now you will be in the getting started page click on get started to reach portainer home page and select your environment.

Click on containers tab and click on add container to get started with portainer.

Install Docker in Debian Linux

mail@vineelsai.com (Vineel Sai) — Mon, 26 Dec 2022 12:00:00 +0000

Docker is an open platform for developing, shipping, and running applications. Docker enables you to separate your applications from your infrastructure so you can deliver software quickly. With Docker , you can manage your infrastructure in the same ways you manage your applications. In the following article, you will know how to install docker in Debian

Prerequisites

Dependencies

Update the system.

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sudo apt update

Install required dependencies

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sudo apt install ca-certificates curl gnupg lsb-release

Setup GPG Key

Add official docker GPG keys to your system
Make keyrings folder

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sudo mkdir -p /etc/apt/keyrings

Add GPG keys to keyrings folder

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curl -fsSL https://download.docker.com/linux/debian/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg

Setup Docker Repository

Add docker download repository to your system

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echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/debian $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

Install Docker

Update the system.

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sudo apt update

Install docker

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sudo apt install docker-ce docker-ce-cli containerd.io docker-compose-plugin

Post Install

Add a docker to the user group to use the docker command without sudo

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sudo usermod -aG docker $USER

Other Operating Systems

If you want to install Docker in other linux distributions check out the following links
For Debian - Install Docker in Debian Linux
For Ubuntu - Install Docker in Ubuntu Linux
For Fedora - Install Docker in Fedora Linux

Install Docker in Fedora Linux

mail@vineelsai.com (Vineel Sai) — Mon, 26 Dec 2022 12:00:00 +0000

Prerequisites

Dependencies

Update the system.

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sudo dnf update

Install required dependencies

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sudo dnf -y install dnf-plugins-core

Setup Docker Repository

Add docker download repository to your system

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sudo dnf config-manager --add-repo https://download.docker.com/linux/fedora/docker-ce.repo

Install Docker

Install docker

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sudo dnf install docker-ce docker-ce-cli containerd.io docker-compose-plugin

Post Install

Add a docker to the user group to use the docker command without sudo

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sudo usermod -aG docker $USER

Other Operating Systems

If you want to install Docker in other linux distributions check out the following links
For Debian - Install Docker in Debian Linux
For Ubuntu - Install Docker in Ubuntu Linux
For Fedora - Install Docker in Fedora Linux

Install Docker in Ubuntu Linux

mail@vineelsai.com (Vineel Sai) — Mon, 26 Dec 2022 12:00:00 +0000

Prerequisites

Dependencies

Update the system.

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sudo apt update

Install required dependencies

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sudo apt install ca-certificates curl gnupg lsb-release

Setup GPG Key

Add official docker GPG keys to your system
Make keyrings folder

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sudo mkdir -p /etc/apt/keyrings

Add GPG keys to keyrings folder

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curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg

Setup Docker Repository

Add docker download repository to your system

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echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

Install Docker

Update the system.

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sudo apt update

Install docker

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sudo apt install docker-ce docker-ce-cli containerd.io docker-compose-plugin

Post Install

Add a docker to the user group to use the docker command without sudo

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sudo usermod -aG docker $USER

Other Operating Systems

If you want to install Docker in other linux distributions check out the following links
For Debian - Install Docker in Debian Linux
For Ubuntu - Install Docker in Ubuntu Linux
For Fedora - Install Docker in Fedora Linux

Create AWS EC2 instance

mail@vineelsai.com (Vineel Sai) — Wed, 08 Dec 2021 12:00:00 +0000

EC2 is a part of AWS, that allows users to rent virtual computers on which to run your own applications. EC2 encourages scalable deployment of applications by providing a web service through which a user can boot a virtual machine, which Amazon calls an instance, containing any software desired. A user can create, launch, and terminate server-instances as needed, paying by the second for active servers

AWS EC2

Go to AWS console https://console.aws.amazon.com/ec2/

Create a new EC2 instance

Click on Create a new instance.
Select the operating system for your EC2 instance.

Select instance type, and click on Next. Be sure to select the right instance type; it costs more money to run a bigger instance, use the AWS Calculator Page to find the right instance type for your project.

On the Configure Instance Details page, make any configuration changes you want to make and click Next. If you don’t see what you want to change, just click Next.

On Add Storage page, type the amount of storage you want to add to your instance in the size column.

On Add Tags page, add tags for your instance, you can leave it empty and click Next.

On Configure Security Groups page, if you have a security group, select it. If you don’t have a security group, click on Create a new security group and add rules to it to allow traffic to your instance. For example, you can allow traffic to port 80 and 443 for HTTP and HTTPS respectively, from any IP address if you are hosting a web server, or you can allow traffic to port 22 for SSH from any IP address if you want to be able to SSH into your instance. And click on Next.

On the Review page, you’ll be asked to create a key pair. If you don’t have a key pair, create one and click on Create Key Pair and give it a name and click on the Download button and save it carefully this is how you will be able to access your instance later, if you lose it you won’t be able to access your instance.
After the key pair is created, click on Launch Instance.

Then you’ll be redirected to the Instances page and you’ll see your new instance.

Access your instance details

You can see more details about the instance by clicking on the instance ID, this will redirect you to the Instance summary page where you can find the Public IP of the instance.

Connect to your instance

Now open a Terminal or Command Prompt and type the following command to access your instance.

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ssh -i [YOUR KEY PAIR NAME].pem ec2-user@[YOUR PUBLIC IP]

In my case, I used the following command to access my instance. For the first time, you’ll be asked to type “yes” to continue.

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ssh -i ubuntu.pem ubuntu@3.110.103.9

You can find exact commands to access your instance by clicking on the connect button on the top right side of the instance details page.

Now you have a new EC2 instance running on AWS ready to use. But keep in mind that EC2 instances can get pretty expensive to run, depending on the traffic you get, so you should be careful when you use them, and set proper budget notifications and limits in the billing console. If you’re not that comfortable with using EC2 and managing all these things, then you can always use the DigitalOcean Droplet to host your VM, where your instance will be charged according to the plan you choose.

Swap on Linux

mail@vineelsai.com (Vineel Sai) — Wed, 01 Dec 2021 12:00:00 +0000

Swap is a portion of the hard disk that is used by the operating system when to store temporary data when the system is running out of memory. It basically works as an extension of the RAM but the data is stored on a disk instead of RAM, but don’t think it is a replacement for RAM because hard disk or even SSDs are much slower than RAM, so the swap is just to prevent the system from crashing if it runs out of memory.

Checking the System for Swap

Run the following command to see existing swap partitions.

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sudo swapon --show

If it returns nothing, then there is no swap on your system and you can create one even if you have swap and you want to increase the size of the swap you can follow along and copy paste the commands below this doesn’t matter much.

Creating a Swap File

Run the following command to create a swap file of size 1GB.

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sudo fallocate -l 1G /swapfile

You can replace the 1G with any size you want, it is recommended to use the size of your RAM if you have 8GB or less ram and half of your RAM if you have more than 8GB.

Enabling the Swap File

The following command will change the permissions of the swap file to be readable and writable by the root only.

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sudo chmod 600 /swapfile

Then run the following command to mark the file as swap.

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sudo mkswap /swapfile

Finally, run the following command to enable the swap file.

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sudo swapon /swapfile

Now run the swapon –show command again to see if the swap file is created and enabled successfully.

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sudo swapon --show

Making swap permanent

Run the following command to enable swap on boot.

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echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

Tuning the swappiness

Swappiness is a value that determines how much memory is swapped out to disk. It is a value between 0 and 100.
Run the following command to see the current swappiness value, it is usually set to 60.

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cat /proc/sys/vm/swappiness

It is not bad if you have a high speed SSD or SSD with a lot of cache, but if you have a slow HDD then it’s better to set the swappiness closer to 0(but not 0).
Run this command to set the current swappiness to 10.

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sudo sysctl vm.swappiness=10

And Edit the file /etc/sysctl.conf and add the following line at the bottom to make it persistent across reboots.

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sudo nano /etc/sysctl.conf

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vm.swappiness=10

Press CTRL+X to exit nano and press Y to save the changes.

Create a New User from the terminal on Ubuntu

mail@vineelsai.com (Vineel Sai) — Sun, 28 Nov 2021 14:00:00 +0000

Root User

Before you get started make sure you are in root user with the following command.

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sudo sh

Adding a New User

Run the following command to create a new user.

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adduser username

You will be asked to enter a password for the user and confirm it and you will be asked to enter some details about the user you can either fill them or leave them empty.

Adding the User to the sudo Group

Run the following command to add the user to the sudo group.

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usermod -aG sudo username

Switching to the New User

Run the following command to switch to the new user.

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su username

Testing sudo access

To make sure that the user has sudo access run a command with sudo.

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sudo apt update

Create a DigitalOcean droplet

mail@vineelsai.com (Vineel Sai) — Sun, 28 Nov 2021 12:00:00 +0000

DigitalOcean Droplets are Linux-based virtual machines (VMs) that run on top of virtualized hardware. Each Droplet you create is a new server you can use, either standalone or as part of a larger, cloud-based infrastructure.

This guide assumes you already have a DigitalOcean account, If not you can create one here.

Create a droplet

Go to DigitalOcean Project Dashboard and click on Get Started with a Droplet.

Then choose the image you want to use, in my case, I chose Ubuntu 20.04.

Then choose the size of the droplet you want to create, I am going with 1GB, $6/month droplet.

Then choose the region you want to create the droplet in, I am going to use Bangalore since it’s nearest to me.

Now enter a password for the droplet, don’t lose it! You will need it later to connect to the droplet.

Then enter the hostname of the droplet, I am going to use ubuntu.

Finally, click on Create Droplet.

Now wait for the droplet to be created, this usually happens in under a minute.

Connect to the droplet

Once the droplet is created, copy the IP address of the droplet and open the terminal in Linux or PowerShell/CMD in windows and use the following command to connect to the droplet.

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ssh root@<IP ADDRESS>

You will be asked to type “yes” to add the SSH key to the droplet and then you will be asked to enter the password for the droplet.

Now you are connected to the droplet and you can start doing things you want to do.

Uninstall Snap in Ubuntu

mail@vineelsai.com (Vineel Sai) — Sat, 27 Nov 2021 14:00:00 +0000

Snap is a packaging format developed by canonical to use in Ubuntu and other Linux distros but there are problems with snaps as they are slow compared to native binaries and consume a lot of disk space and the server side of snapcraft is proprietary, but since it’s their own technology canonical is pushing it too much over other solutions in Ubuntu , so for any of the following reasons if you want to uninstall snaps from your system just follow along.

Uninstall Snaps

Run the following command to list all snaps in your system.

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snap list

Then remove snaps one by one by using the following command

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sudo snap remove --purge snap-name

Uninstall snapd

After removing snaps you can completely remove snap by using the following command

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sudo apt remove --purge snapd

Delete snap cache

Run the following commands to remove any snap configuration or cache files.

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sudo rm -rf /var/cache/snapd/
rm -fr ~/snap # for home user
sudo rm -fr ~/snap # for root user

Hold snap package

Run the following command to prevent snap from auto installing, for example, while installing the chromium package.

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sudo apt-mark hold snapd

Make your own vscode theme from scratch

mail@vineelsai.com (Vineel Sai) — Fri, 26 Nov 2021 10:00:00 +0000

To make a vscode theme you first need to install nodejs and npm before you get started and also make sure you have vscode installed for obvious reasons.

NodeJs - https://nodejs.org/en/
vscode - https://code.visualstudio.com/

Install yo

After you install npm run the following command in your terminal.

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npm install -g yo generator-code

This installs yo and generate-code globally in your system

Create theme

After successfully installation run the following command to create a project

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yo code

You will be asked to select options how you want to create the theme and other questions make sure you fill them all correctly

Edit theme

After you finished it will open the created project in vscode .

Press F5 on your keyboard and it will open a debug window where you can test the theme.

In vscode open the JSON file named your theme name-color-theme.json under the themes folder.
vscode provides a color picker when you hover around the color box in front of the hex code it makes it easy to edit the theme.
Edit the colors you want and save the file.

The theme will instantly reflect in the debug window as soon as you save it.

Feel free to make whatever changes you want to make.

Explore more at - https://code.visualstudio.com/docs/getstarted/themes

Flutter VS React Native in 2022

mail@vineelsai.com (Vineel Sai) — Thu, 25 Nov 2021 15:00:00 +0000

If you want to make a cross platform app that works on both Android & IOS then you have mainly two options to choose from Flutter and React Native . Both of them are great tools to develop cross platform apps but there are some differences between them and different scenarios where you should choose one over the other we’ll have a look at both of them and then we’ll talk about which one is the best for you in this article.

Flutter

Flutter is an open source framework developed by Google for building applications for Android, IOS, Linux, Mac, Windows, and Web. Flutter uses Dart as its programming language. Dart is a relatively new language and it is an object-oriented, class-based, garbage-collected language with C language like syntax. Flutter uses a custom graphics library called Skia to render the app’s UI, it renders the screen pixel by pixel so you get a lot of control over the look and feel of the app and also is very efficient and fast. The views in Flutter are called widgets and you can create your own widgets or download from the internet and use them in your app.

Who are using Flutter

Before you choose a platform you might want to know who else is using them to get an overall idea.

Google

Google Pay
Stadia
Google Ads

Other

BMW
ByteDance
eBay
Dream11
Toyota

Pros of Flutter

Has many 1st party widgets and libraries compared to React Native .
Less code to write compared to React Native .
Looks the same on all platforms.

Cons of Native Development

Uses Dart as its programming language which is a new language and doesn’t have a lot of use other than for Flutter .
Lack of enough 3rd party widgets and libraries.
Small community compared to React Native .

React Native

React Native is an open source framework developed by Facebook it uses JavaScript as its programming language and is based on react framework. The working principles of React Native are virtually identical to React except that React Native does not manipulate the DOM via the Virtual DOM. It runs in a background process directly on the end device and communicates with the native platform via serialized data over an asynchronous and batched bridge. React components wrap existing native code and interact with native APIs via React’s declarative UI paradigm and JavaScript.While React Native styling has a similar syntax to CSS, it does not use HTML or CSS. Instead, messages from the JavaScript thread are used to manipulate native views.

Who are using React Native

Microsoft (Source)

Microsoft Edge
Microsoft Excel
Microsoft OneDrive
Microsoft Outlook
Microsoft SharePoint
Microsoft Teams
Microsoft Word
Skype
Xbox

Other Companies

Walmart
Bloomberg
Coinbase Pro
Discord
Myntra

Pros of React Native

Uses Javascript and is based on react framework so it is very familiar to developers who worked with web development.
Huge 3rd party libraries support.
Looks native on all platforms.

Cons of React Native

Very few inbuilt components.
Poor Memory Management.

Conclusion

React Native has released before Flutter so it has the advantage of having more time to develop and also has a bigger community compared to Flutter but the Flutter community is growing faster every day and is getting more and more popular among startups and multi billion dollar companies. If your app/company wants to build an app fast and want to release it to the public as soon as possible then you would be better of with Flutter . But if you want to build a complex app witch looks native no matter the platform and you don’t mind using lots of 3rd party libraries then you should use React Native .

Native vs Cross-Platform Mobile Development in 2022

mail@vineelsai.com (Vineel Sai) — Thu, 25 Nov 2021 15:00:00 +0000

Before we talk about which way is the best or to be precise which is better for you let’s talk about what is Native and Cross-Platform App development.

Native Development

Native Development refers to building applications specific to a platform by using platform-specific tools & programming languages. When it comes to mobile development we have mainly two platforms Android & IOS, for android we have Java & Kotlin as the primary programming languages, and for IOS we have Objective-C & Swift.

Pros of Native Development

Since these technologies are developed by the same companies that developed the OS you will get better compatibility and performance overall.
Support is another big thing since these tools exist as long as the operating systems exist there will be lots of information and how-to guides available for the technology which is a lifesaver exceptionally if you are a beginner.
Control over the whole application flow which process has to be executed in which thread and all the granular control over the app.

Cons of Native Development

The main con of native app is that it’s very costly and time-consuming to maintain different apps for different platforms.
Keeping the apps look & feel the same across the platforms can also be tricky if you are working on a really big project with multiple teams.

Cross-Platform Development

Cross-Platform development is making applications that work on both Android & IOS. For cross-platform development we have technologies like Flutter , React Native , and Xamarin .

Pros of Cross-Platform Development

It’s very cost-effective to maintain and develop a cross-platform as you don’t have to spend money on developing and maintaining two different code bases for two different teams.
The development of the product will be a lot faster if there is a single codebase.

Cons of Cross-Platform Development

Cross-Platform apps are generally slower than Native apps even though the difference is not prominently visible unless you do some performance benchmarks there certainly is some difference in performance.
Limited Functionality is another major disadvantage of cross-platform apps as there are many limitations when it comes to accessing device hardware like Bluetooth, GPS, and other device sensors.

Conclusion

Well, there is no specific answer to which type of development you should choose it mainly depends on your application and your target audiences. If your app is mainly based on using API calls and displaying that data to users or if your app doesn’t do much processing of data locally it just has to work well with the backend then cross-platform is for you since you want your app to look and behave the same across the platforms. But if your app has anything to do with different sensors then native development is the way to go.

Recycler View in Kotlin

mail@vineelsai.com (Vineel Sai) — Thu, 25 Nov 2021 13:00:00 +0000

To create a recycler view in kotlin you need three classes, an Adapter class to set data to items in the recycler view a data class to give your data a structure, and an activity or fragment class to display the view.

Add dependencies

Add the following dependencies to your build.gradle file

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implementation 'androidx.recyclerview:recyclerview:1.1.0'
implementation 'androidx.cardview:cardview:1.0.0'

Write Code

Create a data class, you can pass the variables you want to access later as parameters in the data class

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data class Item(val text: String)

Create an adapter class

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class Adapter(private val List: List<Item>) : RecyclerView.Adapter<Adapter.ViewHolder>() {
 class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
 val text: TextView = view.findViewById(R.id.text)
 init {
 // You can add onClick Listeners here
 }
 }

 override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
 val item = LayoutInflater.from(parent.context).inflate(R.layout.item, parent, false)
 return ViewHolder(item)
 }

 override fun onBindViewHolder(holder: ViewHolder, position: Int) {
 val element = List[position]
 holder.text.text = element.text
 }

 override fun getItemCount(): Int {
 return List.size
 }
}

Create an Activity where you want to display here I am feeding the view with dummy data you can add whatever data you want

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class MainActivity : AppCompatActivity() {

 override fun onCreate(savedInstanceState: Bundle?) {
 super.onCreate(savedInstanceState)
 setContentView(R.layout.activity_main)
 view.adapter = Adapter(generateDummyList(1000))
 view.layoutManager = LinearLayoutManager(this)
 view.hasFixedSize()
 }

 private fun generateDummyList(size: Int): List<Item> {

 val list = ArrayList<Item>()

 for (i in 0 until size) {
 val item = Item("Item $i")
 list += item
 }
 return list
 }
}

The entire code used is in the GitHub repo — https://github.com/vineelsai26/Recycler-View-Kotlin

Happy Coding!!!

Install Android Studio on Windows

mail@vineelsai.com (Vineel Sai) — Thu, 25 Nov 2021 12:30:00 +0000

Download Android Studio

Go to https://developer.android.com/studio

Click on the Download Android Studio button and accept the license and agreement and click Download Button.

Install Android Studio

Double click on the downloaded .exe file.

Install the program as you would normally.
Click Finish to close the installer.

Now the Android Studio will start automatically.
Choose Do not import settings, then click on OK.

Click Next.

Select standard unless you want to change some configurations and click Next.

Choose a theme and click Next.

Choose SDK location and click Next.

Confirm settings and click Finish.

Click Finish after the SDK download is complete.

Now you are good to go and make your feet wet on your journey to Android Development.

Vineel Sai Blog

Install Portainer in docker Linux

Prerequisites

Docker

Install Portainer

Install Docker in Debian Linux

Prerequisites

Dependencies

Setup GPG Key

Setup Docker Repository

Install Docker

Post Install

Other Operating Systems

Install Docker in Fedora Linux

Prerequisites

Dependencies

Setup Docker Repository

Install Docker

Post Install

Other Operating Systems

Install Docker in Ubuntu Linux

Prerequisites

Dependencies

Setup GPG Key

Setup Docker Repository

Install Docker

Post Install

Other Operating Systems

Create AWS EC2 instance

AWS EC2

Create a new EC2 instance

Access your instance details

Connect to your instance

Swap on Linux

Checking the System for Swap

Creating a Swap File

Enabling the Swap File

Making swap permanent

Tuning the swappiness

Create a New User from the terminal on Ubuntu

Root User

Adding a New User

Adding the User to the sudo Group

Switching to the New User

Testing sudo access

Create a DigitalOcean droplet

Create a droplet

Connect to the droplet

Uninstall Snap in Ubuntu

Uninstall Snaps

Uninstall snapd

Delete snap cache

Hold snap package

Make your own vscode theme from scratch

Install yo

Create theme

Edit theme

Flutter VS React Native in 2022

Flutter

Who are using Flutter

Google

Other

Pros of Flutter

Cons of Native Development

React Native

Who are using React Native

Meta

Microsoft (Source)

Other Companies

Pros of React Native

Cons of React Native

Conclusion

Native vs Cross-Platform Mobile Development in 2022

Native Development

Pros of Native Development

Cons of Native Development

Cross-Platform Development

Pros of Cross-Platform Development

Cons of Cross-Platform Development

Conclusion