Sample app demonstrating nginx + opentracing with Flask

flaskapp-jaeger.py

#!/usr/bin/env python3

import hashlib
import logging
from jaeger_client import Config
from flask_opentracing import FlaskTracing
from flask import Flask, request

from werkzeug.debug import get_current_traceback

from random import randint

upload_app = Flask(__name__)

@upload_app.route("/", methods=['GET', 'POST'])
def default():
    try:
        environ_summary = "ENVIRON:\n\n" + "\n".join(["{0}: {1}".format(k, request.environ[k]) for k in sorted(request.environ.keys())]) + "\n"
        args = "REQUEST ARGS: %s" % request.args
        body = "REQUETS BODY: %s" % request.data
        return "%s\n%s\n%s\n" % (args, body, environ_summary)
    except Exception as e:
        track = get_current_traceback(skip=1, show_hidden_frames=True, ignore_system_exceptions=False)
        track.log()
        abort(500)

@upload_app.route("/upload/", methods=['GET', 'POST'])
@upload_app.route("/upload-http/", methods=['GET', 'POST'])
def upload():
    logging.info("Request headers:\n%s" % request.headers)

    with jaeger_tracer.start_active_span('ProcessUpload') as scope:
        scope.span.log_kv({'ProcessUpload': 'started'})
        scope.span.set_tag('payload-size', int(request.headers.get('Content-Length')) if 'Content-Length' in request.headers else 0)

        response_body = ''

        if 'Content-Length' in request.headers and int(request.headers.get('Content-Length')):
            body = request.stream.read()
            for x in range(1, randint(2, 10)):
                 with jaeger_tracer.start_active_span('SubPart%02d' % x) as sub_scope:
                     sub_scope.span.log_kv({'subpart_iteration': x, 'action': 'begin'})
                     m = hashlib.md5()
                     m.update(body)
                     response_body = response_body + "%d:%d:%s\n" % (x, len(body), m.hexdigest())
                     sub_scope.span.log_kv({'subpart_iteration': x, 'action': 'end'})
            logging.info('ProcessUpload finished with %d iterations' % x)

        else:
            response_body = 'no data was uploaded'

        try:
            scope.span.set_tag('iterations', x)
        except NameError:
            pass

        scope.span.log_kv({'ProcessUpload': 'finished'})

    return response_body

@upload_app.errorhandler(500)
def internal_error(error):
    return "500 error"

if __name__ == "__main__":
    log_level = logging.DEBUG
    logging.getLogger('').handlers = []
    logging.basicConfig(format='%(asctime)s %(message)s', level=log_level)

    config = Config(config={}, service_name='upload-app', validate=True)
    jaeger_tracer = config.initialize_tracer()
    tracing = FlaskTracing(jaeger_tracer, app=upload_app)

    upload_app.debug = True
    upload_app.config['PROPAGATE_EXCEPTIONS'] = True
    upload_app.run(host='127.0.0.1', port=8080)