-
Other contents of the series
- Docker quickly creates lightweight portable container ✓
Docker&flask quickly builds service interfaces✓- Docker and UWSGI high performance WSGI server production deployment requirements
- Docker&gunicorn high performance WSGI server production deployment requirements
- Docker, Nginx and Gunicorn implement load balancing
- Docker&ngxtop and parsing nginx logs in real time
- Docker&supervisor monitors your services
- Docker and PyInstaller two-step build small volume container
- Locust does high concurrency testing on your service
- Postman is a popular API debugging tool
Environment depends on
- This tutorial is based on a Redhat Linux server
python: 3.8.3 click==8.0.1 Flask==2.0.1 flask-limiter ==1.4 itsDangerous ==2.0.1 Jinja2==3.0.1 limits==1.5.1 MarkupSafe==2.0.1 The six = = 1.16.0 Werkzeug = = 2.0.1 WTForms = = 2.3.3Copy the code- Main Contents of this paper
- It includes deploying the Flask service, mounting folders, setting the flask logs, setting the parameter verification section, setting the limit of the number of requests for fixed IP addresses, and setting the IP whitelist.
Docker&flask creates containers
- Python file
- Set debug=True to automatically restart the service when the file is updated
import flask, json
from flask import request
import platform
Create a service, treating the current Python file as a service
app = flask.Flask(__name__)
@app.route('/test', methods=['get'])
def login() :
username = request.values.get('name')
pwd = request.values.get('pwd')
system = platform.system()
systemnode = platform.node()
system_info = "Platform is {0} & running node is {1}".format(system, systemnode)
if username and pwd:
if username=='xiaoming' and pwd=='111':
resu = {'code': 200.'message': 'Login successful'.'system':system_info}
return json.dumps(resu, ensure_ascii=False)
else:
resu = {'code': -1.'message': 'Wrong account password'.'system':system_info}
return json.dumps(resu, ensure_ascii=False)
else:
resu = {'code': 10001.'message': 'Parameters cannot be empty'.'system':system_info}
return json.dumps(resu, ensure_ascii=False)
if __name__ == '__main__':
app.run(debug=True, port=2222, host="0.0.0.0")
Copy the code- Dockerfile file
The FROM python: 3.8 WORKDIR/home/myfirstapi/RUN ln - sf/usr/share/zoneinfo/Asia/Shanghai/etc/localtime COPY.. RUN the PIP install -r requirements.txt -q -i https://pypi.tuna.tsinghua.edu.cn/simple && \ rm -rf /var/cache/apk/* expose 2222 CMD ["python3", "flask_test.py"]Copy the code- We specially set it up for testing convenience
- Debug =True in Python scripts, the service restarts automatically when the script is updated
- The Docker container sets up data volumes so that local changes can be automatically synchronized to the container.
Docker flask build -t test/ Dockerflask :1.0. Then map port 2222 and mount /root/first_api/flask_api to the specified directory of the container docker run -d p 2222:2222 --name docker_flask_api -v / root/first_api/flask_api: / home/myfirstapi/test/dockerflask: 1.0Copy the code- The results are as follows:
Flask Setup log
- Refer to Python’s Logger library
def login(): ... app.logger.debug('this is a DEBUG message') app.logger.info('this is an INFO message') app.logger.warning('this is a WARNING message') app.logger.error('this is an ERROR message') app.logger.critical('this is a CRITICAL message') Copy the code - The result is as follows
Flask adds parameter verification
- Set the validation section
from wtforms.fields import simple from wtforms import Form, StringField, IntegerField from wtforms.validators import Length, Regexp, NumberRange, AnyOf, DataRequired class parameters_validation(Form) : username = StringField(validators=[AnyOf(values = ["xiaoming"."laolitou"])]) pwd = StringField(validators = [DataRequired() Length(max=4.min=2,message="the length of the pwd must between %(min)d and %(max)d"), Regexp(regex="\d+",message="pwd must be start with numbers") ",@app.route('/test', methods=['get']) def login() : form = parameters_validation(request.args) if form.validate(): username = form.username.data pwd = form.pwd.data ... else: return jsonify(form.errors) if __name__ == '__main__': app.run(debug=True, port=2222, host="0.0.0.0") Copy the code - The result is as follows
Flask added IP restrictions
-
Flask Sets the number of IP access times
from flask import Flask from flask_limiter import Limiter from flask_limiter.util import get_remote_address app = Flask(__name__) limiter = Limiter( app, key_func=get_remote_address, default_limits=["5 per day"."2 per hour"])@app.route("/1times") @limiter.limit("1 per day") def slow() : return "Only one visit per day." @app.route("/2times") def fast() : return "Five times a day, two times an hour." @app.route("/nolimits") @limiter.exempt # No access rate limit def ping() : return "Access is unlimited." if __name__ == '__main__': app.run(debug=True, port=2222, host="0.0.0.0") Copy the code -
The result is as follows
- With this, it’s easy to add a limit to the number of times you can offer a monthly service
Flask Sets the IP address whitelist
- Flask Sets the IP address whitelist and provides services for only some IP addresses
from flask import abort, Flask, render_template, request
ALLOWED_IPS = ['10.92'.'10.91']
app = Flask(__name__)
@app.errorhandler(403)
def permission_error(e) :
return Error 403: %s%e
@app.before_request
def limit_remote_addr() :
client_ip = str(request.remote_addr)
valid = False
for ip in ALLOWED_IPS:
if client_ip.startswith(ip) or client_ip == ip:
valid = True
break
if not valid:
abort(403)
@app.route('/', methods = ['GET'])
def home() :
return "Your IP: {}".format(request.remote_addr)
if __name__ == '__main__':
app.run(host='0.0.0.0', debug=True)
Copy the code- The result is as follows
subsequent
- Generally speaking, when we formally provide a service, we need to do load balancing, after all, we need to consider the user experience;
- In nginx load balancing, request limits and IP whitelists can also be configured.