Is Flask effective for a production server-sent-events running on a single machine?

@app.route('/stream')
def notifications_stream():
def notifications():
pubsub = redis_conn.pubsub()
pubsub.subscribe("notifications")
for message in pubsub.listen():
yield 'data: {}\n\n'.format(message['data'])

return Response(stream(), content_type="text/event-stream")

If I run a Flask app that contains the route above, among other routes, will it not block the application, let's say, on 1000 requests, even if I run Gunicorn with multi-threaded workers? Assuming 10 workers, each with 10 threads.

I need clarification on the matter to aid in my development.

/r/flask
https://redd.it/1gnylbk

Code examples: building efficient REST APIs with Django

Recently I had to fix a couple django rest-framework APIs at work that were built as part of a MVP that could not scale properly, which got me thinking of writing a tutorial about different ways of writing APIs in Django.



I provided the dockerized examples that you can easily run, the README contains step-by-step changes I make to the API, starting with a toy example that struggles to return 100k rows in over 30 seconds, optimized down to under 1 second.


I know some of these are controversial opinions of Django, but I thought I'd share them any way, hopefully you pick up something useful. It's a work-in-progress, I plan to add comparison to a Django-ninja as well as backend written in pure Go, as I've come to like those two as well.

https://github.com/oscarychen/building-efficient-api

/r/django
https://redd.it/1gnsqob

Just released: Django Lazy Admin Pagination – Speed up your Django admin!

Hey everyone! 👋

I just launched **Django Lazy Admin Pagination**, a package that makes navigating large datasets in Django admin way faster by loading total counts lazily and updating pagination with AJAX.

# Why use it?

Speed: No more waiting for records count for page loads when working with big datasets.
Easy to use: Just pip install, add to INSTALLED_APPS, and extend your admin with LazyLoadPaginationMixin.

Perfect for any dev dealing with data-heavy Django projects. Check it out and let me know what you think!

Hey everyone! 👋

I just launched Django Lazy Admin Pagination, a package that makes navigating large datasets in Django admin way faster by loading total counts lazily and updating pagination with AJAX.

# Why use it?

Speed: The Django admin panel can be painfully slow when counting total records, especially if you have complex get\_queryset joins. This package skips that full count initially, making things load way faster.
Easy to use: Just pip install, add to INSTALLED_APPS, and extend your admin with LazyLoadPaginationMixin.

Perfect for any dev dealing with data-heavy Django projects. Check it out and let me know what you think!

/r/djangolearning
https://redd.it/1go343k

The Practical Guide to Scaling Django
https://slimsaas.com/blog/django-scaling-performance

/r/django
https://redd.it/1go35ul

An open-source platform for Django developers to build and share profit. What do you think, guys?

Hi Django Community!




Following my post yesterday about finding a fellow Django dev co-founder, I was amazed by the incredible response from developers worldwide. This inspired me to propose a larger idea: What if we created a platform specifically for Django developers to collaborate on profitable projects? Like "Tinder but for builders who match over an idea"

Here's the concept:

\- A free platform where specifically for Django developers ( for now) can share and browse project ideas

\- Developers can choose projects that interest them and find like-minded collaborators

\- Revenue sharing would be transparent and based on repository contributions and git commit.

\- The platform itself would be open-source, built by the community for the community

I'm looking for team members to help build this platform, specifically:

\- A technical lead/CTO with strong full-stack experience and software architecture expertise

\- 2-3 additional contributors interested in building the foundation

If you're interested in joining this initiative, please comment below with:

\- Your role preference (Tech Lead or Contributor)

\- Your experience level with Django

\- Time you can commit weekly

What do you think about this idea? Would this be valuable for our Django community?

/r/django
https://redd.it/1go0h6y

Built this over the weekend - Netflix Subtitle Translator

Motivation: Recently, I've found myself deeply immersed in Japanese movies, dramas, and web series. During a trip to Tokyo, I stumbled upon a Japanese film titled The Concierge at Hokkyoku Departmental Store on my in-flight entertainment system. It had English subtitles, and I was hooked – but unfortunately, I couldn’t finish it before the flight ended. When I got back, I was excited to find it available on Netflix Japan. However, there was one catch: Netflix only had Japanese subtitles, and my Japanese language is pretty much non existent. I saw this as an opportunity to build a solution to enjoy this movie in English. Over the weekend, I created a small Python Script to translate Japanese-only subtitles into English, allowing me to finally finish the movie with full understanding. This may not be the most scalable setup, but it does the job!

What does this project do ? : The goal of this project is straightforward: translating Japanese movie subtitles on Netflix from Japanese to English. The motivation came from a lack of available English subtitles, making this project both an interesting technical challenge and a useful solution for my specific needs. It’s currently set to Japanese -> English, but

/r/Python
https://redd.it/1gny0ew

Escaping from Anaconda

Sometime a friendly snake can turn dangerous.

Here are some hints

Escaping from Anaconda

/r/Python
https://redd.it/1go58y5

Monday Daily Thread: Project ideas!

# Weekly Thread: Project Ideas 💡

Welcome to our weekly Project Ideas thread! Whether you're a newbie looking for a first project or an expert seeking a new challenge, this is the place for you.

## How it Works:

1. **Suggest a Project**: Comment your project idea—be it beginner-friendly or advanced.
2. **Build & Share**: If you complete a project, reply to the original comment, share your experience, and attach your source code.
3. **Explore**: Looking for ideas? Check out Al Sweigart's ["The Big Book of Small Python Projects"](https://www.amazon.com/Big-Book-Small-Python-Programming/dp/1718501242) for inspiration.

## Guidelines:

* Clearly state the difficulty level.
* Provide a brief description and, if possible, outline the tech stack.
* Feel free to link to tutorials or resources that might help.

# Example Submissions:

## Project Idea: Chatbot

**Difficulty**: Intermediate

**Tech Stack**: Python, NLP, Flask/FastAPI/Litestar

**Description**: Create a chatbot that can answer FAQs for a website.

**Resources**: [Building a Chatbot with Python](https://www.youtube.com/watch?v=a37BL0stIuM)

# Project Idea: Weather Dashboard

**Difficulty**: Beginner

**Tech Stack**: HTML, CSS, JavaScript, API

**Description**: Build a dashboard that displays real-time weather information using a weather API.

**Resources**: [Weather API Tutorial](https://www.youtube.com/watch?v=9P5MY_2i7K8)

## Project Idea: File Organizer

**Difficulty**: Beginner

**Tech Stack**: Python, File I/O

**Description**: Create a script that organizes files in a directory into sub-folders based on file type.

**Resources**: [Automate the Boring Stuff: Organizing Files](https://automatetheboringstuff.com/2e/chapter9/)

Let's help each other grow. Happy

/r/Python
https://redd.it/1goetbj

I'm learning Flask from Miguel grinbergs forum but feel overwhelmed and don't know how to learn properly.

I'm stuck like the 5th chapter but not it just feels like I'm learning to learn i feel like I won't remember anything what did you guys do.

/r/flask
https://redd.it/1gobv5s

What programming language would you recommend I learn to make a inventory management/POS system for windows application and web based.



/r/flask
https://redd.it/1golss9

urlfor - rendertemplate generates .html

Hi everyone,

I'm currently having a big issue with Flask, and I can't seem to figure out what's going wrong. I've tried everything I can think of, but the problem persists. I'm hoping someone here can help me understand and fix this issue.

Problem Description:

I have a Flask application with the following route definitions in my app.py:

pythonCode kopierenfrom flask import Flask, rendertemplate

app = Flask(name)

@app.route('/')
def index():
return rendertemplate('index.html')

@app.route('/blog')
def blog():
return rendertemplate('blog.html')


In my index.html template, I have a link that should direct users to the blog page:

<!-- index.html -->
<a href="{{ urlfor('blog') }}" class="xx">View Blog</a>


The Issue:

When I load the index page in the browser, the {{ url_for('blog') }} is being resolved to blog.html instead of /blog. This means the generated HTML looks like this:

<a href="blog.html" class="xx">View Blog</a>

So when I click on the link, it tries

/r/flask
https://redd.it/1goaanu

pipe-operator: Elixir's pipe operator in Python

TLDR: pipe-operator is an open-source python package which brings similar features to elixir's |> tap then to Python, with 2 vastly different implementations. Because why not :D

\---

Hey there! Thought it might be of interest to some of you! I come from Python but lately I've been working with Elixir (mostly at work) and came to really enjoy its pipe operator |> and its related features like tap, then, and shortcut syntaxes. So I thought to myself: "could be fun to bring this to python". So I did, and the **pipe-operator** project was born.

# What My Project Does

It provides similar features to elixir |>, allowing you to chain operations without using intermediary variables. Through 2 very different implementations, you can pass the result of the previous expression as the first parameter of the next one.

As for those 2 very different implementation, they are:

A pythonic class-based one, which is fully compatible with linters and type-checkers
And an elixir-like one, with a syntax resembling elixir's, which will drive you linters mad

# Target Audience

I don't think anyone would be using this in production/work projects, but it can be a fun tool for developers' side projects who enjoy functional programming.

# Quick demo

Python implementation:



/r/Python
https://redd.it/1go69ha

I wrote some code that allow donations on a site. The first form allows you to input your email and the amount. The problem is in the first form I added the email and the amount to the db. But if I don't click pay in the second form the code is still added to the db. How do I fix this problem?

Here is the code.

app.py/routes.py

https://pastebin.com/NismhUbf

Here is the html. I did not include the success or failure page.

templates/stripe_payment/donations.html

https://pastebin.com/Hsr0YAVK

Here is a picture of the first form. https://imgur.com/a/ejBL7QL

Here is a picture of the second form https://imgur.com/a/Y98ahWu

models.py
https://pastebin.com/QU31ZCgi

forms.py + functions.py

https://pastebin.com/nFiCyYPQ

/r/flask
https://redd.it/1go9rtl

D How to visualize the effect of an LLM attention layer on a set of tokens with an image model

Is it possible to visualize how an LLM “imagines” a token before and after processing it through the attention layer by feeding the token embeddings into an image model? I understand you can't copy paste it over, but is there a way to capture the latent transformation caused by the attention layer and apply this transformation to the embedding space of an image model?

For example if i were to enter "poor man," into an LLM the embedding for "man" would shift toward "beggar" while entering "royal man" it could move closer to "king." I want to visualize that change. Then you could transfer the embedding for man to an image model and it would create the something like a beggar or a king in this example.

It could make a really cool visualization if you captured the transformation after each attention layer and made a video by interpolating each step.

/r/MachineLearning
https://redd.it/1gojg09

UK: Python Developer job market? Is it worth it?

So i’ve been looking at a change of career and one that i’m currently exploring is in the IT industry as a developer.

Python seems to be the starting point for newbs so going down that route.

Looking at jobs in the UK though and theres 100’s of applications for each role. Is it a diluted market?

With no degree, i’d be looking to build my knowledge over the next 12-24 months in Python and create a couple of programmes to add to a portfolio.

Would I have any chance of getting a job in the industry with that alone?

Whats the market like in the UK for other developers? Is it a nightmare trying to find a job?

Is it all worth it?! 😵‍💫

Any help would be appreciated! TIA

/r/Python
https://redd.it/1gos2hg

Building User Interfaces in a web app using Flask

Kindly visit the link to learn the building blocks for a web app in Flask. Also spread the word and let's learn together.

https://flask-india.hashnode.dev/building-user-interfaces-in-flask

/r/flask
https://redd.it/1go5rfv

Beginner in Django, Choosing the Right Storage for Files (Local vs. Cloud)

Hi everyone,

I’m new to Django and web development with only a few months of experience. I’ve built some small projects, but I’m now working on one that involves storing files (like PDFs, images, and ZIP files). So far, I’ve only stored files on the same server as my app, but I’d like to understand other storage options better.

Specifically, I’m trying to decide between local storage (keeping files on the same server) and cloud storage (like AWS S3, Google Cloud Storage, etc.). Here’s what I’d love to know:

1. Pros and Cons What are the main benefits and drawbacks of local storage versus cloud storage for a small-scale project? I’m not dealing with huge amounts of data here, just a few files for now.
2. Setup Difficulty How hard is it to set up cloud storage with Django as a beginner? I’ve heard there’s more configuration involved compared to just saving files locally, so any insight on what to expect would be helpful.
3. Costs Are there any affordable cloud storage options for small-scale projects? I’m on a limited budget, so I’m wondering if the cost is worth it for something that’s not too data-intensive yet.

Any advice or beginner-friendly tips on storage options would

/r/django
https://redd.it/1goroaj

Long startup time of the app (cold boot)

Hello, been using Flask for years now and I have this project that has been developed over the years. It has grew to around 400 routes.

The structure of the app is:

https://preview.redd.it/r31gktsamb0e1.png?width=723&format=png&auto=webp&s=65d3e4764678545b07387de91592bfa697442cfe

main.py file has all the routes for the app. I have tried using the Flask Blueprints today for one group of routes but it didn't make much difference to app startup time. Handlers are then used for handling the routes. Handlers can also call models which are used with Google Datastore for database. There are also some custom Python scripts for handling different CSV and XML files that users can upload.

The problem is that app startup time is around 30 seconds on local environment and around 40 seconds on Google App Engine (when instance is cold booting and loading the app for the first time). After the initial startup then the app is quite fast.

This means that users have to wait 40 seconds for the app to startup before it can serve the request. Even if I would put min-instances to 1 that would partly solve the issue but still, if a new instance would be needed (because of auto-scaling when app is under higher load) the startup time would

/r/flask
https://redd.it/1gp0j2g

please need HELP

I have a Flask application where, on the index HTML page, I can input parameters and calculate the path loss value. There's also a "Show Visualization" button, which is supposed to take the latitude, longitude, and path loss values to display a map visualization. However, I'm currently unable to get the map visualization to work.

please guide me.

[https://github.com/saurabh-acharya-912/RF](https://github.com/saurabh-acharya-912/RF)

github link for this.






from flask import Flask, render_template, request, jsonify

app = Flask(__name__)

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/heatmap')
def heatmap():
   
    lat = request.args.get('lat')
    lon = request.args.get('lon')
    effective_path_loss = request.args.get('effectivePathLoss')

    return render_template('heatmap.html', lat=lat, lon=lon, effective_path_loss=effective_path_loss)

if __name__ == '__main__':
    app.run(debug=True)





/r/flask
https://redd.it/1gp1163

Celery Workers take 2.5 Hours to START on ECS

Here's a link to my previous post where I was facing issues in ECS related to running the migrations. https://www.reddit.com/r/django/s/nl53QfhjR1

Currently my Djnago application is starting as expected in ECS and immediately without any delays.
The issue I'm facing right now is with the celery workers which are unable to start and shows logs after 2-3 hours later. I have used the 'flower' tool to check if it's a cloudwatch logs issue but the worker itself doesn't register until 2-3 hours later.
This is all running on ECS Fargate. The described issue came after some changes in the application. The same image is working in my UAT cluster though. I have checked the env files and ECS Task Definition multiple times.

Suggest if you know something regarding this.

/r/django
https://redd.it/1gp20wq