Forem: Shrawan

Cloudflare R2 - Generating Presigned URL

Shrawan — Sat, 30 Jul 2022 06:49:00 +0000

Since, cloudflare R2 is compatible with S3 API, we can simply use boto3 to work with R2 as wll

import logging
import boto3
from botocore.exceptions import ClientError

from botocore.client import Config


def create_presigned_url(bucket_name, object_name, expiration=3600):
    s3_client = boto3.client('s3',
            endpoint_url='https://<ACCOUNT_ID>.r2.cloudflarestorage.com',
            aws_access_key_id='<ACCESS_KEY>',
            aws_secret_access_key='<SECRET_KEY>',
            config=Config(signature_version='s3v4'),
      )
    try:
        response = s3_client.generate_presigned_url('get_object',
                    Params={'Bucket': bucket_name,
                                    'Key': object_name},
                                     ExpiresIn=expiration)
    except ClientError as e:
        logging.error(e)
        return None

    # The response contains the presigned URL
    return response

if you want to use R2 with Django have a look into https://djangotherightway.com/using-cloudflare-r2-with-django-for-storage

Python Pattern Matching -Switch Case

Shrawan — Fri, 15 Jul 2022 04:07:57 +0000

Switch Statement from Python 3.10

In Python 3.10, A match statement and case statements of patterns with related actions have been added to provide structural pattern matching. Sequences, mappings, primitive data types, and class instances are examples of patterns. Programs can branch on data structures, execute specific actions based on distinct sorts of data, and extract information from complicated data types using pattern matching.

Basic syntax

match status:
    case pattern_1:
        action_1
    case pattern_2:
        action_2
    case _:
        action_wildcard

Example 1 (Getting weekday with switch statement in Python)

def week_day_from_number(number):
    match number:
        case 1:
            return "Sunday"
        case 2:
            return "Monday"
        case 3:
            return "Tuesday"
        case 4:
            return "Wednesday"
        case 5:
            return "Thursday"
        case 6:
            return "Friday"
        case 7:
            return "Saturday"
        case _:
            return "Week has only 7 days"

Example 2 (Getting HTTP error from HTTP status code with Switch statement)

def http_error(status):
    match status:
        case 200:
            return "OK"
        case 201:
            return "Created"
        case _:
            return "Error"

SSL with certbot on nginx/apache on Ubuntu Server

Shrawan — Fri, 15 Jul 2022 04:02:57 +0000

First Thing first

sudo add-apt-repository ppa:certbot/certbot
sudo apt-get update

On Nginx Server

sudo apt-get install python3-certbot-nginx
sudo certbot --nginx

On Apache Server

sudo apt-get install python3-certbot-apache
sudo certbot --apache

Note [if using Cloudflare]: If you have used cloudflare as DNS hosting and have proxied your DNS record to this server, then automatic domain verification of while generating certificate will fail. In this case remove proxy from cloudflare DNS record and then try again else you can choose other methods for your domain verfication