Object serialization deserialization ORM/ODM documentation

https://marshmallow.readthedocs.io/en/2.x-line/quickstart.html#serializing-objects-dumping

#python #marshmallow #ORM #ODM #readthedocs

https://www.youtube.com/watch?v=XMu0T6L2KRQ&list=PLEsfXFp6DpzTOcOVdZF-th7BS_GYGguAS

#python #django #rest

Heading to Zoodroom, wish me luck 😍
#job #python

Is there a way to create ObjectID from an INT in MongoDB?

import bson

def object_id_from_int(n):
    s = str(n)
    s = '0' * (24 - len(s)) + s
    return bson.ObjectId(s)

def int_from_object_id(obj):
    return int(str(obj))

n = 12345
obj = object_id_from_int(n)
n = int_from_object_id(obj)
print(repr(obj))  # ObjectId('000000000000000000012345')
print(n)  # 12345

#mongodb #objectid #pymongo #python #bson #int

https://code-maven.com/serialize-datetime-object-as-json-in-python

#python #json #dump #datetime

What does select_related do in Django?

select_related does a join in case needed on the DB side and reduce query counts. Let's look at an example:

# Hits the database.
e = Entry.objects.get(id=5)

# Hits the database again to get the related Blog object.
b = e.blog

In the above code 2 queries are issued in DB side. First it gets Entry record and then blog is fetched from DB when e.blog is called. And here’s select_related lookup:

# Hits the database.
e = Entry.objects.select_related('blog').get(id=5)

# Doesn't hit the database, because e.blog has been prepopulated
# in the previous query.
b = e.blog

You can follow foreign keys in a similar way to querying them. If you have the following models:

from django.db import models

class City(models.Model):
    # ...
    pass

class Person(models.Model):
    # ...
    hometown = models.ForeignKey(
        City,
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
    )

class Book(models.Model):
    # ...
    author = models.ForeignKey(Person, on_delete=models.CASCADE)

Then a call to Book.objects.select_related('author__hometown').get(id=4) will cache the related Person and the related City:

# Hits the database with joins to the author and hometown tables.
b = Book.objects.select_related('author__hometown').get(id=4)
p = b.author         # Doesn't hit the database.
c = p.hometown       # Doesn't hit the database.

# Without select_related()...
b = Book.objects.get(id=4)  # Hits the database.
p = b.author         # Hits the database.
c = p.hometown       # Hits the database.

#python #django #select_related #join #database #models

https://www.toptal.com/python/introduction-python-microservices-nameko

#nameko #microservice #rabbitmq #python #docker #greenlet

One of the methods to document your API is APIDOC. It uses annotation in variety of languages like Python, PHP, JS, etc. At the below code block you can see an example in Python:

"""
@api {get} /user/:id Request User information
@apiName GetUser
@apiGroup User

@apiParam {Number} id Users unique ID.

@apiSuccess {String} firstname Firstname of the User.
@apiSuccess {String} lastname  Lastname of the User.
"""

To read more about the APIDOC itself and the installation process head over to link below:

- http://apidocjs.com/

#javascript #js #python #apidoc #apidocjs #api #documentation #rest #annotation

DO NOT USE UWSGI multi-threaded mode with alpine image!

I've been stuck on this issue for a couple of days as our service returned 503 Gateway timeout while our server load was totally ok around 1.0 (1m load average). So our load test got failed at the be beginning of the test! We found out it is related to docker base image of python alpine. Use python slim image instead. Or in case you have many changes you can stick with alpine and change thread to 1 in uswgi configuration file.


#docker #alpine #uwsgi #python #slim #respawn