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How to Read a CSV File from Amazon S3 Using Python (With Headers and Rows Displayed)

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  Introduction If you’re working with cloud data, especially on AWS, chances are you’ll encounter data stored in CSV files inside an Amazon S3 bucket . Whether you're building a data pipeline or a quick analysis tool, reading data directly from S3 in Python is a fast, reliable, and scalable way to get started. In this blog post, we’ll walk through: Setting up access to S3 Reading a CSV file using Python and Boto3 Displaying headers and rows Tips to handle larger datasets Let’s jump in! What You’ll Need An AWS account An S3 bucket with a CSV file uploaded AWS credentials (access key and secret key) Python 3.x installed boto3 and pandas libraries installed (you can install them via pip) pip install boto3 pandas Step-by-Step: Read CSV from S3 Let’s say your S3 bucket is named my-data-bucket , and your CSV file is sample-data/employees.csv . ✅ Step 1: Import Required Libraries import boto3 import pandas as pd from io import StringIO boto3 is...
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How to Configure Firewall For an Application

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A firewall is a set of rules. When a data packet moves into or out of protected network space, its contents (in particular, information about its origin, its target, and the protocol it plans to use) are tested against the firewall rules to see if it should be allowed through.


Firewall configuration


How a Firewall concept works

Let's say that the web server has to be open to incoming web traffic from anywhere on earth using either the insecure HTTP or secure HTTPS protocol.

Because your developers and admins will need to get into the backend from time to time to do their work, you’ll also want to allow SSH traffic, but only for those people who’ll need it. Requests for any other services should be automatically refused.

A Linux machine can be configured to apply firewall rules at the kernel level through a program called iptables.

Creating table rules isn't all that difficult; the syntax can be learned without too much fuss. But, in the interest of simplifying your life, many Linux distributions have added their own higher-level tools for abstracting the job.


Firewall functionality


It is also available through hardware appliances manufactured by companies like Juniper and Cisco. Those proprietary devices run on their own operating systems with unique syntax and design.

For larger enterprise deployments involving hundreds of servers spread across multiple networks, such tools will often make a lot of sense, but there's a remarkable amount that you can accomplish with any old Linux box for a tiny fraction of the cost. 


Firewall


As you might have guessed from its name, firewalld is part of the systemd family. firewalld can be installed on Debian/Ubuntu machines, but it's there by default on Red Hat and CentOS. If you're just too excited by firewalld to even consider trying anything else, here's how to install it and get it running on Ubuntu:

# apt update # apt install firewalld

To confirm that the firewall is working, try browsing your server's web root. If the site is unreachable, then firewalld is doing its job.

You’ll use the firewall-cmd tool to manage firewalld settings from the command line. Adding the --state argument returns the current firewall status:

# firewall-cmd --state running

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