Flask code explainers

python

from flask import Blueprint, render_template, jsonify, request, abort
 
from .models import Article

Content negotiation in a Flask Blueprint

content-negotiation http-headers routing

Intermediate 7 steps

python

from werkzeug.routing import BaseConverter, ValidationError
from flask import Flask, jsonify, abort

Custom URL converters in Flask

url-routing validation converters

Intermediate 6 steps

python

from flask import Blueprint, jsonify
from marshmallow import Schema, fields, validate, EXCLUDE
from webargs.flaskparser import use_args

Validating query params in Flask with webargs

validation schema query-building

Intermediate 10 steps

python

import json
import time
import queue

Server-Sent Events streaming in Flask

server-sent-events streaming pub-sub

Advanced 9 steps

python

from flask import Blueprint, request, jsonify
from marshmallow import Schema, fields, validate, ValidationError, EXCLUDE
 
from .models import db, User

How a Flask blueprint validates and creates users

validation rest-api schema

Intermediate 8 steps

python

import random
 
import click
from faker import Faker

Building a Flask seed command with Click

cli database seeding orm

Intermediate 7 steps

python

import smtplib
from email.message import EmailMessage
from threading import Thread

Sending welcome emails off the request thread in Flask

background-threads app-context email

Intermediate 8 steps

python

from flask import Blueprint, request, url_for, jsonify, abort
from flask.views import MethodView
 
from .models import Article, db

Building a paginated JSON API with Flask MethodView

rest-api pagination class-based-views

Intermediate 10 steps

python

from flask import Blueprint, render_template, request, redirect, url_for, flash
from werkzeug.security import check_password_hash
 
from .models import User, db

A change-email route in Flask

blueprints form-validation password-hashing

Intermediate 8 steps

python

import hashlib
import os
from datetime import timedelta

Serving cacheable static assets in Flask

http-caching etag conditional-requests

Intermediate 8 steps

python

from flask import Blueprint, jsonify, request, abort
 
v1 = Blueprint("users_v1", __name__)
v2 = Blueprint("users_v2", __name__)

Versioning a Flask API with Blueprints

api versioning blueprints rest

Intermediate 7 steps

python

import os
from datetime import timedelta

Class-based config in a Flask app factory

configuration app-factory inheritance

Intermediate 7 steps

python

import time
 
from flask import Flask, g, request

Timing requests with Flask hooks

middleware request-lifecycle instrumentation

Intermediate 5 steps

python

from decimal import Decimal, ROUND_HALF_UP
 
from babel.numbers import format_currency
from flask import Flask

Building a currency Jinja filter in Flask

template filters decimal precision internationalization

Intermediate 6 steps

python

from functools import wraps
 
import jwt
from flask import current_app, g, jsonify, request

How a JWT auth decorator works in Flask

decorators authentication jwt

Intermediate 6 steps

python

from flask import Blueprint, jsonify, request, abort
from flask_caching import Cache
 
cache = Cache(config={"CACHE_TYPE": "RedisCache", "CACHE_REDIS_URL": "redis://localhost:6379/0"})

Custom cache keys for Flask endpoints

caching redis cache-invalidation

Intermediate 7 steps

python

from flask import Flask, g, jsonify, request, abort
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

Per-request SQLAlchemy sessions in Flask

database sessions request lifecycle connection management

Intermediate 7 steps

python

from functools import wraps
from flask import Blueprint, session, request, redirect, url_for, flash, render_template
from werkzeug.security import check_password_hash

Session-based auth with a Flask Blueprint

authentication decorators sessions

Intermediate 9 steps