todos[todo_id] = request.form['data']
span.set_tag("put_todo_data", request.form['data'])
return {todo_id: todos[todo_id]}
if __name__ == '__main__':
# Create flask instance
app = Flask(__name__)
# Create Restful instance
api = Api(app)
# Set the opentracing configuration
tracer = init_tracer('hello-world')
# Add the tracer to the app
flask_tracer = FlaskTracer(tracer, True, app)
# Create parent span
parent_span = flask_tracer.get_span()
# Add default route to HelloWorld
api.add_resource(HelloWorld, '/')
# Add route /todo to TodoSimple
api.add_resource(TodoSimple, '/todo/<string:todo_id>')
# Start the flask app
app.run(debug=False, host='0.0.0.0')
class GrTFlaskMiddleware(object):
def __init__(self,
app,
name,
host='localhost',
rate=0,
header='GROFERS_TRACE_ID',
patches=[]):
self.cfg = Config(config={
'sampler': {
'type': 'const',
'param': rate
},
'local_agent': {
'reporting_host': host
},
'trace_id_header': header
},
service_name=name)
self.app = app
self.initialized = False
app.before_request(self._start_trace)
app.after_request(self._end_trace)
permitted_patches = [
'mysqldb',
'psycopg2',
'strict_redis',
'sqlalchemy',
'tornado_http',
'urllib',
'urllib2',
'requests',
]
final_patches = []
for patch in patches:
if not patch in permitted_patches:
raise ValueError('{} is not a valid patch'.format(patch))
else:
final_patches.append(
'opentracing_instrumentation.client_hooks.{}.install_patches'
.format(patch))
install_patches(final_patches)
def _start_trace(self):
if not self.initialized:
self.tracer = self.cfg.initialize_tracer()
self.ftracer = FlaskTracer(self.tracer, False, self.app)
self.initialized = True
span = self.ftracer.get_span(request)
if span is None:
span = self.tracer.start_span(request.endpoint)
mgr = RequestContextManager(span=span)
mgr.__enter__()
request.span = span
request.mgr = mgr
def _end_trace(self, response):
request.span.finish()
request.mgr.__exit__()
return response