main.py

from api import bp, api
from flask_cors import CORS, cross_origin
from flask import Flask, request
from api_routes import search_ns

config = {
    'ORIGINS': [
        'http://localhost:3000/'
    ]
}

app = Flask(__name__, instance_relative_config=True)
cors = CORS(app, resources={'/*': {'origins': config['ORIGINS']}})

app.register_blueprint(bp)
app.config['CORS_HEADERS'] = 'Content-Type'
app.config.from_mapping(SECRET_KEY='dev')
app.config['DEBUG'] = True
app.config['RESTPLUS_VALIDATE'] = True
app.config['SWAGGER_UI_DOC_EXPANSION'] = 'list'

cross_origin(automatic_options=True)

api.add_namespace(search_ns)

@app.after_request
def after_request(response):
    response.headers.add('Access-Control-Allow-Origin', '*')
    response.headers.add('Access-Control-Allow-Methods', 'POST')
    response.headers.add('Access-Control-Allow-Headers', 'Content-Type')
    return response

if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5000, debug=True)