Create Weather Service

Now we will create the weather service app. The news service app is also based of Flask API and simply calls the WeatherAPI. The weather service app will be configured on port:3002

Sample request/response

A request involves 2 attributes:

  • appid : This is the 2 letter code for the country
  • q : Represents the city name

Sample request/response will look like this:

  • Sample request for the weather in New York city
PS C:\Users\aniru\workspace\github\nginx-docker> curl https://api.openweathermap.org/data/2.5/weather?appid=deb96cff96df7c74e93e62661b91c3c2'&'q=new%20york
  • Sample response for the above request : 
{"coord":{"lon":-74.006,"lat":40.7143},"weather":[{"id":804,"main":"Clouds","description":"overcast clouds","icon":"04n"}],"base":"stations","main":{"temp":279.94,"feels_like":276.89,"temp_min":277.88,"temp_max":281.12,"pressure":1005,"humidity":53},"visibility":10000,"wind":{"speed":4.63,"deg":230},"clouds":{"all":100},"dt":1674012646,"sys":{"type":2,"id":2008101,"country":"US","sunrise":1673957823,"sunset":1673992477},"timezone":-18000,"id":5128581,"name":"New York","cod":200}

Create weather service

Create file weather.py and copy the following contents :

from flask import Flask, request
from flask_restful import Api
import json
import requests

app = Flask(__name__)
api = Api(app)
@app.route('/weather')
def weather():
    # sample request: http://api.openweathermap.org/data/2.5/weather?appid=deb96cff96df7c74e93e62661b91c3c2&q=new%20york
    city_name = request.args.get('city')
    api_key = "deb96cff96df7c74e93e62661b91c3c2"
    base_url = "http://api.openweathermap.org/data/2.5/weather?"
    complete_url = base_url + "appid=" + api_key + "&q=" + city_name
    response = requests.get(complete_url)
    return response.json()

if __name__ == '__main__':
    app.run(host="0.0.0.0",port='3002',threaded=True,debug=True)

This tells weather app to parse any incoming request and pass on the request to the OpenWeather API. The app returns the response returned by the weather API as is.

Create Dockerfile

We will create a new dockerfile called Dockerfile.weather. This will be referenced in the docker-compose.yml file. Copy the following contents into Dockerfile.weather.

# use Python 3.11 image
FROM python:3.11-alpine

# install dependencies:
COPY requirements.txt .
RUN pip install -r requirements.txt
EXPOSE 3002
COPY weather.py .

# run the application:
CMD ["python", "weather.py"]

This will tell docker to:

  • Use python base image 3.11-alpine
  • Reference requirements.txt in the image to install required software
  • Expose port 3002
  • Copy news.py to the image
  • Start the weather service