SQLAlchemy vs PostgreSQL Functions

Hey guys, we're using heavily PostgreSQL (we let it handle all business logic, mapping, etc.). We use Flask only to handle requests, call queries on the DB and then respond back the return from the Database.
Now a problem is that SQL is hard to read once it reaches a certain amount of complexity (and that can happen really fast). Production is very slow and the code becomes hard to maintain. On the other hand, one can argue that it's more performant than using a lightweight ORM like SQLAlchemy. Did any of you make similar experience? Would you let handle PostgreSQL everything, as we do, or would you move the logic to Flask?
I hope to read some advices.
Have a great weekend!

/r/flask
https://redd.it/8ff41v

Basic Docker (Compose) Django + Postgres Setup
https://www.youtube.com/watch?v=90LCcim-wHQ

/r/django
https://redd.it/8ff028

A python multithreaded logging handler package that streams records to AWS services(S3, Kinesis)
https://github.com/omrikiei/aws_logging_handlers

/r/Python
https://redd.it/8ffvg8

Changing Matplotlib fonts: Neophyte who uses Juno Jupyter for scientific plotting.

I know this may be a little more specialized to Matplotlib, as I’m one of those lowly matl*b to Python ship jumpers, for the purposes of plotting pretty data and performing analyses on it. But I’m stuck somewhere that while trivial, will nevertheless drive me nuts as a strongly visual person: If anyone could provide guidance for changing the font on either a global or per-plot basis for all labels and legends in a plot you would have my eternal gratitude. Using rcParams as in the matplotlib documentation gives:

/home/nbuser/anaconda3_501/lib/python3.6/site-packages/matplotlib/font_manager.py:1320: UserWarning: findfont: Font family ['sans-serif'] not found. Falling back to DejaVu Sans
(prop.get_family(), self.defaultFamily[fontext]))

/r/JupyterNotebooks
https://redd.it/8fbqru

[AF] Jinja macros and field formatting.

Within jinja2 templates I'm using a macro to render the fields in my forms. The macros handle all the formatting, label placement, validators, etc. Like so:

_forms.html
{% macro render_field(field) %}
<hr class="forms">
{{ field.label }}
{% if field.flags.required %}
*
{% endif %}
<br>
{{ field(**kwargs)|safe }}
{% if field.errors %}
{% for error in field.errors %}
<span class="flash">{{ error }}</span><br>
{% endfor %}
{% endif %}
{% endmacro %}


template code:
{% from "_forms.html" import render_field %}
{% extends "base.html" %}

{{ render_field(form.search_by) }}
{{ render_field(form.search_term) }}

{% endblock %}


My question is this: is there any way to pass width/height values to the engine via the macros? If you simply declare the fields directly you can pass parameters to format the field, but these parameters break the macros.

template code:
{% extends "base.html" %}

{{ form.description.label }}{{ form.description(size="100") }}

{% endblock %}

/r/flask
https://redd.it/8fbeil

Rookie Question. I have a /static/ folder defined for image assests. However my dynamic Routes invalidate the static path.. Help?

Hey all,

So i use the following convention for loading assets.
<img src="static/img/dashboard_entries.png" alt="" />

However I just changed my dashboard route from:
@app.route('/dashboard/')
to
@app.route('/dashboard/<string:userID>/')

and now my image link doesn't work.
<img src="static/img/dashboard_entries.png" alt="" />
This is because it fully qualifies to:
http://127.0.0.1:5000/dashboard/19/static/img/dashboard_entries.png
instead of its previous:
http://127.0.0.1:5000/dashboard/static/img/dashboard_entries.png

How does one handle the use of dynamic routes and static assets in the static folder?

Thanks in advance.

Tim.

/r/flask
https://redd.it/8e9wia

How are you (regularly) deploying new Django projects?

I find myself spending 2\+ hours every time I want to deploy a new Django project. I've started using django\-cookie\-cutter which has made a big difference in development as I can use Docker \(and our other developers can therefore get set up much more easily\) but getting those projects deployed to a server is still a frustrating and tedious task. I use Linode and do everything manually per\-project \(add SSH keys, updates hosts, install docker, pull project set up\).

Would something like beanstalk help here? Any suggestions to help simplify this process? Do other people struggle with the time deployment takes?

/r/django
https://redd.it/8fiz89

13 Python GUI Libraries
http://prosof.site/13-python-gui-libraries

/r/Python
https://redd.it/8fipvd

What exactly is caching and how do I add it to an app I have on heroku?

I have a data science type application where I am getting public information from FPDS and SAM gov't website. The site is currently on heroku.

I would like cache views so if a person is researching more than one company they can quickly go back to earlier pages without having to fetch the results from the database everytime.

Based on my limited knowledge that is what casheing does?

Second, I am looking at [flash-caching](https://flask-caching.readthedocs.io/en/latest/#) and it doesn't appear to be that difficult to implement to the route's I would like to cashe.

The question is on heroku, you wouldn't use `simplecashe` would you? Would you use a different cashe strategy? From the docs the `CASHE_TYPE` can be `simple`, `redis`, `memcached` and serveral more. On heroku would I need to store the cache on something like redis or can I store it in memory?

/r/flask
https://redd.it/8e4yj1

Blockchain Explained in 7 Python Functions
https://www.kdnuggets.com/2018/04/blockchain-explained-7-python-functions.html

/r/Python
https://redd.it/8fiftx

A tool to generate Jupyter notebooks programmatically

I recently found myself needing to generate many Jupyter notebooks in different directories, that were all very similar, save for a few differences in a variable name.

Hence, I decided to write a Python script that generates a Jupyter notebook from an input template:

https://github.com/ismailuddin/jupyter-nb-templater

Maybe it might be useful to somebody? Comments and suggestions welcome!

/r/IPython
https://redd.it/8fk8sz

How to create a count down timer on Django?

Hi guys,

I just started Django. Though it is really challenging but it is exciting.

I just wrote a little hello world web app and also a web app that displays time.

I want to get my hands dirty before I move on to the next topic.

I want to create a countdown timer on Django.

I don't know how to go about it and I need your help guys.

if you have any little project for beginners, pls I would love to read your suggestion as well.

/r/django
https://redd.it/8fkpb0

The Forgotten Optional `else` in Python Loops
https://medium.com/@s16h/the-forgotten-optional-else-in-python-loops-90d9c465c830

/r/Python
https://redd.it/8fkbem

What is flask used for

Hi, I am currently learning flask but would like to know how exactly are flask applications used in software development of companies.

For instance if a company is using the MEAN stack, where do the flask applications come into play?

The tutorial for the flask framework illustrates its use as a web application. However if I only need it as a web server, do I need to care about the templates?

Thank you all in advance! I’m a beginner in software engineering and would like to have a fuller picture of how different frameworks come together in a company.

Edit: Grammar

/r/flask
https://redd.it/8e7yli

How to prevent a customer from adding items just before the Confirm Payment button is clicked?

First, I am sorry I post it here because r/webdev is all about frontend, and r/backend is empty.

Currently I am working on an ecommerce project based on django-oscar. Since its accompanying paypal integration library is abandoned(and it's a two-step checkout), I decided to use BrainTree SDK to implement Paypal Express Checkout. Paypal EC gives you a button on the final review page that customer can click to have a pop-up window that they can login to paypal and pay.

The problem is, on the review page, the button needs a pre-determined checkout amount. That means when the page is generated, it has to fill in the button with the amount in the cart. If the customer add items after the review page is loaded but before clicking the button, the checkouted cart will have more items than those are paid.

I know django-oscar has a "freeze basket" function. But it will remove all items from the cart. I think a good place to call it would be during the review page generation. But I can't think of a reliable way to determine whether and when to restore the cart if the customer stops at review page and decides to checkout later, which I think would happen quite a lot.

Thanks for your help!

/r/django
https://redd.it/8fk1c1

Widgets wont show in HTML/Azure/NBViewer

So from my running my notebook the widgets work fine, but saving them as html, uploading them to azure/github/nbviewer and then opening them through the link, the widgets don't display.

With a basic example I get "
interactive(children=(IntSlider(value=5, description='n', max=10), Output()), _dom_classes=('widget-interact',…"

displayed where the output widget should be.

Is there any way I can share my notebook so that the other user does not need to install ipython/jupyter to see the widgets?

/r/IPython
https://redd.it/8fli20

[D] Statement on Nature Machine Intelligence
https://openaccess.engineering.oregonstate.edu/home

/r/MachineLearning
https://redd.it/8fmtr9

Where is the option to change the local host port?

Sometimes to spice things up I change the local host port, and I was wondering where this resides in Django?

/r/djangolearning
https://redd.it/8fnuz9

You can accidentally override local variables with PEP 572 -- Assignment Expressions

/r/Python
https://redd.it/8fokpw

[D] Why is Z-dimension for GANs usually 100?

I'm playing around with GANs, I've got a question which I can't find answer for. Why is Z-dimension (random vector noise) for GANs usually 100? I saw a lot of GitHub projects and online tutorials, seems like the random vector has always the size of 100. Is it confirmed that it gives the best results? What if I changed that to e.g 1000? How does it affect the generated images?

/r/MachineLearning
https://redd.it/8fqcfv