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Useful SFTP terminal commands

First Step - Connect to a remote computer sftp -i ~/.ssh/LightsailDefaultKey-ap-south-1.pem ubuntu@52.66.180.155 Similar to ssh command. Output: Connected to 52.66.180.155. sftp> Remote and Local computer commands When we relay basic terminal commands at sftp> like 'pwd , ls , cd , and it is executed at the remote computer. Basic terminal commands above when prefixed with l like lpwd , lls , lcd and etc. it is executed at a local computer. For e.g. List all files in the present working directory at the remote computer: sftp> ls List all files in the present working directory at the local computer: sftp> lls Sending a local computer file to present the working directory of a remote computer sftp> put /Users/mj/Downloads/test.png Output Uploading /Users/mj/Downloads/test.png to /home/ubuntu/test.png /Users/mj/Downloads/tech-mrit-prod.ovpn 100% 13KB 382.9KB/s 00:00 References How To Use SFTP to Securely Transfer Files with a Re
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FastAPI first shot

Setup on my Mac (Macbook Pro 15 inch Retina, Mid 2014) Prerequisite Python 3.6+ (I used 3.7.x. I recently reinstalled OS after cleaning up disk, where stock Python 2.7 was available. I installed Pyenv and then used it to install 3.7.x). I already had a git repo initialized at Github for this project. I checked that out. I use this approach to keep all the source code safe or at a specific place 😀. I set the Python version in .python-version file. I also initialize the virtual environment using pyenv in venv folder. I started the virtual environment. FastAPI specific dependencies setup Now I started with basic pip commands to install dependency for the project. I saved dependencies in requirements.txt  the file. Minimal viable code to spin an API Server FastAPI is as cool as NodeJS or Go Lang (?) to demonstrate the ability to spin an API endpoint up and running in no time. I had the same feeling for the Flask too, which was also super cool. app/main.py: from typing i

Setting Clickhouse column data warehouse at Google Cloud Compute Engine VM

I didn't have a Google Cloud account associated with my email, so I signed up for one. It needs a valid Credit Card and mobile number to check if you are human. On successful sign up I get 300$ to spend within 3 months. Creating a free forever Google Cloud Compute Engine VM As per Google Cloud documentation you can have 1 non-preemptible e2-micro VM instance (1GB 2vCPU, 30GB Disk, etc.) per month free forever in some regions with some restrictions. I wanted the following stuff in my VM before I can install Clickhouse on to that: Ubuntu 20.x LTS SSH access from my machine Enabling SSH-based access to Google Compute Engine VM Step 1 Created an ssh private and public key on my mac using the following command ssh-keygen -t rsa -f ~/.ssh/gcloud-ssh-key -C mrityunjay -b 2048 Step 2 Copied the public key from the console using the following command: cat ~/.ssh/gcloud-ssh-key.pub output ssh-rsa <Gibrish :)> mrityunjay Step 3 I went to Google Cloud Console > Co

Initial research on FastAPI

I already used Flask in the past. I know about the extensive usage of DJango Framework in the Python community. Both are decent frameworks for web and API development in the Python world. As usual, at the beginning of a new project, I was unconsciously checking out the health and relevance of my technology selection. I came across FastAPI framework and noticed it because of the following facts: Selected in InfoWorld Best Open Source Software Award 2021 . Simplicity of Flask. Faster than Flask as it uses ASGI (Asynchronous Server Gateway Interface) . Adaptation among large product companies like Uber , Netflix and others. More than 38K stars on Github as on 17 Nov 2021. Remember Flask has more than 55K stars on Github. FastAPI is catching up fast. More to come.

Extend and reuse an existing AirByte destination connector

AirByte is an open-source ELT (Extract, Load, and Transformation) application. It heavily uses containerization for the deployment of its various components. On the local machine, we need docker to run it. AirByte has an impressive list of source and destination connectors available. One of my use case data destinations is the  ClickHouse data warehouse and its destination connector is not yet (2021-12-08) available. As per the documentation, It seems that creating a destination connector is a non-trivial job. It's a great idea to build an open-source ClickHouse destination connector. However, I tried avoiding the temptation to create one because of the required effort. AirByte has a  MySql destination connector available. ClickHouse provides a MySQL connector for access from any MySQL client. We need to configure Clickhouse to give support for the MySQL connector. Accessing ClickHouse from AirByte using its MySQL destination connector looks promising. However, when I tri

Pyenv to manage multiple Python versions

1. Intro to Pyenv In this article, we will learn about Pyenv to manage multiple Python versions effectively. Python comes bundled with Mac OS, however, they are 2.X version. Python 2.X is outdated and they are not suggested for any new development. The latest Python version is 3.8 (As of 20 April 2020). When we install Python 3.8 using the installer package and try to run python  the command we were surprised to see it's still pointing to the python 2.X version. Python website download page\ % python WARNING: Python 2.7 is not recommended. This version is included in macOS for compatibility with legacy software. Future versions of macOS will not include Python 2.7. Instead, it is recommended that you transition to using 'python3' from within Terminal. Python 2.7.16 (default, Dec 13 2019, 18:00:32) [GCC 4.2.1 Compatible Apple LLVM 11.0.0 (clang-1100.0.32.4) (-macos10.15-objc-s on darwin Type "help", "copyright", "credits" or "lic

Java Functional Interface

1. What is Functional Interface An interface with only one abstract method is called Functional Interface. Pre Java 8, there was no concept of Functional Interface. However, interfaces like Comparator and Runnable have only one abstract method. Hence they fell into the Functional Interface category in Java 8 unintentionally. 2. Example 2.1 getSellingPrice method snippet from App.Java package org.geekmj.java8; public class App { public static void main(String[] args) { // } private static float getSellingPrice(float cost, float couponDiscount, DiscounterFunctionalInterface discounter) { return cost - couponDiscount - discounter.discount(cost); } } Here, we have a method getSellingPrice , with three arguments cost , couponDiscount and discounter . discounter is of type DiscounterFunctionalInterface . It calculates the selling price for an item. 2.2 DiscounterFunctionalInterface.java package org.geekmj.java8; @FunctionalInterface public interface DiscounterFunctiona