Example – Using Non-Global State

For obvious reasons it may be desirable for your application to have some non-global state that is used by your route handlers.

Below we have created a simple ItemStore class that has an instance of Klein as a class variable app. We can now use @app.route to decorate the methods of the class.

import json

from klein import Klein


class ItemStore:
    app = Klein()

    def __init__(self):
        self._items = {}

    @app.route('/')
    def items(self, request):
        request.setHeader('Content-Type', 'application/json')
        return json.dumps(self._items)

    @app.route('/<string:name>', methods=['PUT'])
    def save_item(self, request, name):
        request.setHeader('Content-Type', 'application/json')
        body = json.load(request.content)
        self._items[name] = body
        return json.dumps({'success': True})

    @app.route('/<string:name>', methods=['GET'])
    def get_item(self, request, name):
        request.setHeader('Content-Type', 'application/json')
        return json.dumps(self._items.get(name))


if __name__ == '__main__':
    store = ItemStore()
    store.app.run('localhost', 8080)