All Questions
Tagged with python design-patterns
132 questions
2
votes
1
answer
131
views
A Design Pattern for a component which both writes to and reads from an ordered event log
I am searching for a good design for a set of components I am writing for a system.
I believe it is very likely there is a Design Pattern, or set of Design Patterns, which could be combined to solve ...
- 320
1
vote
2
answers
107
views
Dynamic web application hitting database on front page load to fetch profile image
Folks, I am in middle of writing a web application (Python/Flask) where home page has user profile image in the navbar which is coming from a database (blob), I am wondering if this is a good practice....
- 19
2
votes
2
answers
562
views
Is this architecture overkill? What is a good way to architect this software?
I have an algorithm I am trying to implement that has steps 1 to 5. There are several different ways I could implement each step. Each calculation step is essentially just an astronomy calculation, ...
- 187
2
votes
1
answer
247
views
How do I structure my functions (and classes?) which interact with my Database/ORM?
So I am working on my first project using SQLite and SQLModel as ORM. Creating and handling the first table in my database was easily structured: A function for each CRUD-Operation.
But now I have ...
- 251
2
votes
1
answer
261
views
Design patterns for long chains of computations in python (functions vs classes?)
A recurring pattern which I see in my code is chaining together a lot of functions. This is the result of a large number of processing steps needed for a given task. This could be e.g. a data ...
- 251
0
votes
1
answer
239
views
How do we nest decorators?
It is possible to nest many decorators.
@decorator_one
@decorator_two
@decorator_three
@decorator_four
def some_silly_function():
pass
How do we write a decorator class so that the order in which ...
- 145
1
vote
3
answers
988
views
Storing multiple instances on a Singleton?
RefactoringGuru's example Singleton in Python has an _instances dictionary field
class Singleton(type):
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls....
- 145
-1
votes
1
answer
218
views
How can I use builders for products with incompatible interfaces?
I am working on a program to automatically design heater units based on varying client specifications.
The process for creating each heater is quite involved and requires multiple optional steps ...
- 97
1
vote
1
answer
463
views
What is an apporpriate design pattern when dealing with Pandas and databases?
We're dealing with a lot of "data analysis", basically different sorts of data mangling, aggregations and calculations using Pandas. Usually, the data is time series data.
All underlying ...
- 13
0
votes
0
answers
133
views
Python Typechecking versus TypedDicts?
From what I understand from this answer, it is not possible to use a typeddict and typechecking in a function. So for example, if one has a function:
def some_func(some_int: int, some_dict:...
- 225
0
votes
1
answer
474
views
Multiple models/controllers python app
I am trying to tinker with the MVC pattern and I have a problem when trying to design the MVC structure. I need a model for products, however as I need to manage more and different data, I can help ...
- 13
1
vote
1
answer
4k
views
Return type specification if a Python function output type, is dependent on the input arguments of that function?
Context
Suppose one has a list of algorithms, which each have a multiple run/parameter configurations. Next, one wrote a generic function def get_mdsa_configs(self) -> List[MDSA_config]: that ...
- 225
2
votes
2
answers
393
views
Design Pattern: How to handle changing format of text file?
I have a text file which is evolving and thus, difficult to manage. Hence, I am going to rewrite the code from scratch. Since, only few parts of the txt file change with a newer version, from the ...
- 129
1
vote
1
answer
314
views
Where to create repository instances?
I've several repositories. To make them testable, I add the ORM session in the constructor.
class Repository:
def __init__(session):
self.session = session
def save(object):
self.session()...
- 153
2
votes
1
answer
160
views
The notion of configurable strategies
I'm designing an algorithm that matches entries based on some notion of "proximity" (for the sake of discussion, assume we're matching floats). Furthermore:
The input is a scalar and a ...
- 233