Appstats are only working for one WSGIApplication - python

I've split handlers between 2 python files (main.py and main_cms.py). app.yaml defines the URLs that each python file will handle.
When I look at the Appstats, only the handlers from one of the 2 python files are profiled (the ones from main.py).
The 'magic' of webapp_add_wsgi_middleware(app) always used to work just fine, until the split. How can I make Appstats recording apply to all handlers?
appengine_config.py:
def webapp_add_wsgi_middleware(app):
from google.appengine.ext.appstats import recording
app = recording.appstats_wsgi_middleware(app)
return app
app.yaml:
builtins:
- appstats: on
...
- url: /services/.*
script: main.application
- url: /cms.*
script: main_cms.application
main.py and main_cms.py:
application = webapp2.WSGIApplication(url_mapping, config=config)
Running python2.7 / GAE 1.6.3, the dev_appserver.py shows Appstats correct for all handlers. The described problem is only seen in production.

Related

Flask Logging in ElasticBeanstalk

I am trying to set up Logging for my Flask app which is deployed in ElasticBeanstalk.
I have a basic logging in place that prints stuff in my console.
But on deploying in Beanstalk, I am not able to see any of the application logs.
Is there any specific config that needs to be setup in order to achieve this?
Just sharing a sample code.
user.py
import logging
class User(Resource):
def details(self):
user_info = "Hello"
logging.info(user_info)
You can add a config file to your .ebextensions folder that adds your application's logs to the logs that EB downloads automatically.
Assuming that your application logs to a folder called logs in the Flask app root, you would make a file called .ebextensions/logging.config that looks like this:
files:
"/opt/elasticbeanstalk/tasks/taillogs.d/your_app_name_logs.conf" :
mode: "000644"
owner: root
group: root
content: |
/var/app/current/logs/*.log
(Which is a slight variation on the official documents here: https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-features.logging.html)
Then, after you deploy, you should be able to use the GUI to pull down logs.

Python & GAE - StringType write() argument type parsing

When running dev_appserver.py ., I get the following error when trying to access http://localhost:8080:
Traceback (most recent call last):
File "/usr/local/Cellar/python#2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/wsgiref/handlers.py", line 86, in run
self.finish_response()
File "/usr/local/Cellar/python#2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/wsgiref/handlers.py", line 128, in finish_response
self.write(data)
File "/usr/local/Cellar/python#2/2.7.15_1/Frameworks/Python.framework/Versions 2.7/lib/python2.7/wsgiref/handlers.py", line 204, in write
assert type(data) is StringType,"write() argument must be string"
AssertionError: write() argument must be string
I've searched and it seems to come back to my app.yaml file, per these links:
SO Question for GAE Assertion Error
Russian Question site with
same information
I'm just not sure how to go about debugging it. Below is my app.yaml file and my main.py file. I'm super new to the GAE platform and any help would be appreciated.
app.yaml file:
application: gqtimer
version: 1-56
runtime: python27
api_version: 1
threadsafe: false
handlers:
- url: /favicon.ico
static_files: static/images/favicon.ico
upload: static/images/favicon.ico
- url: /_ah/login_required
script: main.py
- url: /static
static_dir: static
- url: /player.*
script: main.py
login: required
- url: /stat.*
script: main.py
login: required
- url: .*
script: main.py
libraries:
- name: django
version: "1.11"
main.py file:
#!/usr/bin/env python
#
import config
import os
import sys
# Force sys.path to have our own directory first, so we can import from it.
sys.path.insert(0, config.APP_ROOT_DIR)
sys.path.insert(1, os.path.join(config.APP_ROOT_DIR, 'externals'))
os.environ["DJANGO_SETTINGS_MODULE"] = "settings"
import wsgiref.handlers
from google.appengine.ext import webapp
from google.appengine.dist import use_library
use_library('django', '1.2')
from handlers import error, timer, do_openid_login
def main():
application = webapp.WSGIApplication([('/', timer.ExportHandler),
('/_ah/login_required', do_openid_login.OpenIdLoginHandler),
('/player/([-\w]+)', timer.PlayerHandler),
('/player/([-\w]+)/archives', timer.ArchivesHandler),
('/stat/([-\w]+)', timer.StatHandler),
('/stat/([-\w]+)/delete', timer.StatDeleteHandler),
# If we make it this far then the page we are looking
# for does not exist
('/.*', error.Error404Handler),
],
debug=True)
wsgiref.handlers.CGIHandler().run(application)
if __name__ == '__main__':
main()
Indeed, your app.yaml file might not be properly mapping your application code. You need to:
take the application variable outside of the main() function so that it becomes a global variable in the main.py module (and maybe rename it to app as well - just to stay inline with the official convention and documentation examples)
replace the script: main.py statements from your app.yaml's handlers with main.application (or main.app if renamed as mentioned above) - this is the reference to the above-mentioned global variable. From the script row in the Handlers element table:
A script: directive must be a python import path, for example,
package.module.app that points to a WSGI application. The last component of a script: directive using a Python module path is
the name of a global variable in the module: that variable must be a
WSGI app, and is usually called app by convention.
I'd also recommend explicitly passing the app.yaml as argument to dev_appserver.py instead of the app's directory (. in your case) - occasionally the auto-detection doesn't behave as expected. It's also the only way to run multiple services and/or using a dispatch.yaml file for routing, so it's a good habit.

How can I make a Python package which serves a website with Flask to work with Apache?

I have written a Python package hwrt (see installation instructions if you want to try it) which serves a website when executed with
$ hwrt serve
2014-12-04 20:27:07,182 INFO * Running on http://127.0.0.1:5000/
2014-12-04 20:27:07,183 INFO * Restarting with reloader
I would like to let it run on http://www.pythonanywhere.com, but when I start it there I get
19:19 ~ $ hwrt serve
2014-12-04 19:19:59,282 INFO * Running on http://127.0.0.1:5000/
Traceback (most recent call last):
File "/home/MartinThoma/.local/bin/hwrt", line 108, in <module>
main(args)
File "/home/MartinThoma/.local/bin/hwrt", line 102, in main
serve.main()
File "/home/MartinThoma/.local/lib/python2.7/site-packages/hwrt/serve.py", line 95, in main
app.run()
File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 739, in run
run_simple(host, port, self, **options)
File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 613, in run_simple
test_socket.bind((hostname, port))
File "/usr/lib/python2.7/socket.py", line 224, in meth
return getattr(self._sock,name)(*args)
socket.error: [Errno 98] Address already in use
I only found this in the documentation:
Flask
never use app.run(), it will break your webapp. Just import the
app into your wsgi file...
By searching for wsgi file, I found mod_wsgi (Apache). However, I don't understand how I can adjust my current minimalistic Flask application to work with that. Currently, the script behind hwrt serve is:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""Start a webserver which can record the data and work as a classifier."""
import pkg_resources
from flask import Flask, request, render_template
from flask_bootstrap import Bootstrap
import os
import json
# hwrt modules
import hwrt
import hwrt.utils as utils
def show_results(results, n=10):
"""Show the TOP n results of a classification."""
import nntoolkit
classification = nntoolkit.evaluate.show_results(results, n)
return "<pre>" + classification.replace("\n", "<br/>") + "</pre>"
# configuration
DEBUG = True
template_path = pkg_resources.resource_filename('hwrt', 'templates/')
# create our little application :)
app = Flask(__name__, template_folder=template_path)
Bootstrap(app)
app.config.from_object(__name__)
#app.route('/', methods=['POST', 'GET'])
def show_entries():
heartbeat = request.args.get('heartbeat', '')
return heartbeat
#app.route('/interactive', methods=['POST', 'GET'])
def interactive():
if request.method == 'POST':
raw_data_json = request.form['drawnJSON']
# TODO: Check recording
# TODO: Submit recorded json to database
# Classify
model_path = pkg_resources.resource_filename('hwrt', 'misc/')
model = os.path.join(model_path, "model.tar")
print(model)
results = utils.evaluate_model_single_recording(model, raw_data_json)
# Show classification page
page = show_results(results, n=10)
page += 'back'
return page
else:
# Page where the user can enter a recording
return render_template('canvas.html')
def get_json_result(results, n=10):
s = []
for res in results[:min(len(results), n)]:
s.append({res['semantics']: res['probability']})
return json.dumps(s)
#app.route('/worker', methods=['POST', 'GET'])
def worker():
# Test with
# wget --post-data 'classify=%5B%5B%7B%22x%22%3A334%2C%22y%22%3A407%2C%22time%22%3A1417704378719%7D%5D%5D' http://127.0.0.1:5000/worker
if request.method == 'POST':
raw_data_json = request.form['classify']
# TODO: Check recording
# TODO: Submit recorded json to database
# Classify
model_path = pkg_resources.resource_filename('hwrt', 'misc/')
model = os.path.join(model_path, "model.tar")
results = utils.evaluate_model_single_recording(model, raw_data_json)
return get_json_result(results, n=10)
else:
# Page where the user can enter a recording
return "Classification Worker (Version %s)" % hwrt.__version__
def get_parser():
"""Return the parser object for this script."""
from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter
parser = ArgumentParser(description=__doc__,
formatter_class=ArgumentDefaultsHelpFormatter)
return parser
def main():
app.run()
if __name__ == '__main__':
main()
Ok, a not so non-sequitur answer to your question is around what mod_wsgi does to interface with your app. A typical flask app would look something like this:
from flask import Flask
app = Flask(__name__)
app.route("/")
def hello():
return "Holy moly that tunnel was bright.. said Bit to NIC"
if __name__ == "__main__":
app.run()
Unfortunately, Apache has no way to know what to do with this (though the app would run happily on its own). In order to get the app and Apache to play nice together we're going to use something called mod_wsgi. What Mod_WSGI does that's important to us, is that it provides a known interface (a file type called wsgi) that's going to wrap our application and initialize it so that we can serve it through Apache.
I'm going to assume you are using a python virtual environment, but if you aren't you can omit the step that deals with this in the instructions below. If you're curious why virtual environments are so great, feel free read about the python ecosystem.
Also - you can include an extra flag (assuming you are running wsgi as a daemon) to automatically reload the daemon whenever you touch or alter your wsgi file. This is quite useful during development and debugging so I'll include is below.
Anyway, let's get started. I'll break this down to steps below.
Configuring Apache for mod_wsgi
Enable mod_wsgi in Apache:
sudo apt-get install libapache2-mod-wsgi
Edit your /etc/apache2/sites-available/<yoursite>.conf.
<VirtualHost interface:port>
WSGIDaemonProcess yourapp user=someUser processes=2 threads=15
WSGIProcessGroup yourapp
# In this case / refers to whatever relative URL path hosts flask
WSGIScriptAlias / /absolute/path/to/yourapp.wsgi
<Directory /path/to/your/main/py/file/ >
# Use good judgement here when server hardening, this assumes dev env
Order allow,deny
Allow from all
Require all granted
#The below enables 'auto-reload' of WSGI
WSGIScriptReloading On
</Directory>
# If you want to serve static files as well and bypass flask in those cases
Alias /relative/url/to/static/content/
<Directory /absolute/path/to/static/root/directory/>
Order allow,deny
Allow from all
</Directory>
</VirtualHost>
Create your yourapp.wsgi file and put it in the appropriate place: Be wary of file permissions!
#!/usr/bin/python
import sys
import logging
# Activate virtual environment.
# If you are not using venv, skip this.
# But you really should be using it!
activate_this = "/path/to/venv/bin/activate_this.py"
execfile(activate_this, dict(__file__=activate_this))
# Handle logging
logging.basicConfig(stream=sys.stderr)
sys.path.insert(0, "/path/to/your/main/py/file/")
from YourMainPyFileName import app as application
application.secret_key = "your_secret_key"
Reload Apache and troubleshoot problems. I set this up probably every few weeks for a different project or idea I have and... I usually have to fix one thing or another when doing it from scratch. Don't despair though! Flask has great documentation on this.
Once you've done all this you should be at a place where flask runs all on its own. The sample flask app above is the actual code I use to verify everything works whenever I set this up.
This was left here in case it's some use, but is not really directly related to the question...
The answer here is to use x-send-file. This takes advantage of letting Apache do what it's good at (serving static content), while at the same time first letting flask (or other python framework) do it's work first. I do this often to let flask handle my auth layers in single page web apps and have so far been happy with the results.
Doing so requires two things:
First - Enable xsendfile on Apache2 sudo apt-get install libapache2-mod-xsendfile.
Second - Alter your apache2 configuration so allow x-send-file headers:
Alter your conf file in /etc/apache2/sites-available/<yoursite>.conf and add...
XSendFile On
XSendFilePath /path/to/static/directory
This can be entered top level within the <Virtualhost></Virtualhost> tags.
Don't forget to restart Apache sudo service apache2 restart.
Finally - Configure your flask app to use x-send-file in your app.py file:
app.user_x_sendfile = True
Note: Must be done after app initialization. Consequently can also be passed as an initialization parameter.
Flask has documentation on this (excerpt below):
use_x_sendfile
Enable this if you want to use the X-Sendfile feature. Keep in mind that the server has to support this. This only affects files sent with the send_file() method.
New in version 0.2.
This attribute can also be configured from the config with the USE_X_SENDFILE configuration key. Defaults to False.
I ran into a similar issue #moose was having. Getting connection refused and couldnt even telnet localhost 5000.
Turns out theres a ports.conf file i had to add Listen 5000
Happy days.

How to load a basic module from a cron job

I am having trouble loading my GAE module.
My cron.yaml:
cron:
- description: call frontend instance to call module
url: /callLoadAndProcess
schedule: every day 01:00
timezone: America/New_York
Then the relevant part of my app.yaml:
- url: /callLoadAndProcess
script: callLoadAndProcess.application
secure: always
login: admin
Now my callLoadAndProcess.py:
import sys
import webapp2
import os
import urllib2
import logging
from google.appengine.api import modules
class callLoadAndProcess(webapp2.RequestHandler):
def get(self):
modules.start_module("loadandprocess","1")
application = webapp2.WSGIApplication([('/callLoadAndProcess', callLoadAndProcess)],debug=True)
For my module, I have a loadandprocess.yaml, which is:
application: [application name]
module: loadandprocess
version: 1
runtime: python27
instance_class: B4_1G
basic_scaling:
max_instances: 1
handlers:
- url: /.*
script: loadAndProcess.application
login: admin
And finally, loadAndProcess.py is the script I want run as a backend module:
class loadAndProcess(webapp2.RequestHandler):
def get(self):
#DO STUFF
application = webapp2.WSGIApplication([('/loadAndProcess', loadAndProcess)],debug=True)
In my development server, when I try to run the cron job via the admin page, I get the following error:
line 138, in _CheckAsyncResult
raise mapped_error()
InvalidVersionError
I feel I set it up correctly... and the version numbers match.. did I miss something? Thanks!
To run the app locally, specify both .yaml files to dev_appserver.py:
dev_appserver.py -A your-app-id application.yaml worker.yaml

Yaml file addressing in GAE using Python

Here is the file structure :
--src
-----\app.yaml
-----\bl
-----\bl\calc.html
-----\calc.py
-----\Main.py
I want to get to this address "localhost/bl/calc.html" and here is my yaml file:
- url: /bl
static_dir: bl
- url: /bl/.*
script: calc.py
- url: /.*
script: Main.py
In the Main.py I have this :
from calc import Calc
application = webapp.WSGIApplication([
('/', MainPage),
('/bl/calc', Calc)
], debug=True)
But I got just "This webpage is not found" for both http://localhost/bl/calc and http://localhost/bl/calc.html
I got really confused With this YAML file and GAE
I Dont know how to fix it. Should I have same application config in Calc file ?
Directives in app.yaml are evaluated in order, top to bottom. Because you have a static_dir directive for /bl/ before the script handlers for /bl/ and .*, any requests for that path will be satisfied by the static directory, not the script. Decide which you want - static or script - and add only that to app.yaml.
The yaml file tells what file to run for a given path. Since you're setting up a WSGIApplication in Main.py that will handle requests to /bl/calc with your Calc object, you don't need the lines in your app.yaml file specifying calc.py. Remove those lines and your program should work.

Categories