from flask import Flask
from opencensus.ext.flask.flask_middleware import FlaskMiddleware
from opencensus.trace.propagation.trace_context_http_header_format import TraceContextPropagator

app = Flask(__name__)
middleware = FlaskMiddleware(app, propagator=TraceContextPropagator(), blacklist_paths=['_ah/health'])

@app.route('/')
def hello():
    return 'Hello World!'

if __name__ == '__main__':
    import logging
    logger = logging.getLogger('werkzeug')
    logger.setLevel(logging.ERROR)
    app.run(host='localhost', port=8080, threaded=True)