I am following this web.py Hello World example:
https://library.linode.com/web-servers/nginx/python-uwsgi/ubuntu-12.04-precise-pangolin#sph_more-information
Now I get the "Hello World!" example from above page perfectly to run in my Browser, but when I want to change the application to my need, e.g. make a fully AJAX app out of it like this:
urls = ('/(.*)', 'Index')
application = web.application(urls, globals())
web.config.debug = True
class Index:
def POST(self):
content = web.input(_method='post')
return 'Ajax Test Data'
if __name__ == '__main__':application.run()
I get the following error (even if I make minor changes to the "application" function from Linode)
uWSGI Error
Python application not found
How can I get this to work with my own code?
I uninstalled the Debian packages and installed the pip package with build-in Python. I also had to clean up / unify my .ini and -xml configuration files.
I then started my app with
uwsgi -s /tmp/uwsgi.sock -w app
The biggest help came from this document
However, I encountered a web module not found error, so I rolled back to the Linode example and am currently fiddling around with it, still trying to get my app called from inside the application wrapper.
Hi Look at this stackoverflow post:uwsgi error python application not found
You need to kill the old uWSGI process, which is searching for the old instance of the app, which no longer exists because you changed it.
Instead of running the app with if __name__ == '__main__':application.run(), you need to "export" WSGI application to uWSGI. By default uWSGI looks for a WSGI callable named application, but the application you have is not a WSGI callable. So remove if __name__ == '__main__':application.run() and replace application = web.application(urls, globals()) with application = web.application(urls, globals()).wsgifunc().
Related
I'm trying to trigger a python module (market order for Oanda) using web hooks(from trading view).
Similar to this
1) https://www.youtube.com/watch?v=88kRDKvAWMY&feature=youtu.be
and this
2)https://github.com/Robswc/tradingview-webhooks-bot
But my broker is Oanda so I'm using python to place the trade. This link has more information.
https://github.com/hootnot/oanda-api-v20
The method is web hook->ngrok->python. When a web hook is sent, the ngrok (while script is also running) shows a 500 internal service error and that the server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.
This is what my script says when its running (see picture);
First says some stuff related the market order then;
running script picture
One thing I noticed is that after Debug it doesn't say Running on... (so maybe my flask is not active?
Here is the python script;
from flask import Flask
import market_orders
# Create Flask object called app.
app = Flask(__name__)
# Create root to easily let us know its on/working.
#app.route('/')
def root():
return 'online'
#app.route('/webhook', methods=['POST'])
def webhook():
if request.method == 'POST':
# Parse the string data from tradingview into a python dict
print(market_orders.myfucn())
else:
print('do nothing')
if __name__ == '__main__':
app.run()
Let me know if there is any other information that would be helpful.
Thanks for your help.
I fixed it!!!! Google FTW
The first thing I learned was how to make my module a FLASK server. I followed these websites to figure this out;
This link helped me set up the flask file in a virtual environment. I also moved my Oanda modules to this new folder. And opened the ngrok app while in this folder via the command window. I also ran the module from within the command window using flask run.
https://topherpedersen.blog/2019/12/28/how-to-setup-a-new-flask-app-on-a-mac/
This link showed me how to set the FLASK_APP and the FLASK_ENV
Flask not displaying http address when I run it
Then I fixed the internal service error by adding return 'okay' after print(do nothing) in my script. This I learned from;
Flask Value error view function did not return a response
Dash is a dashboard-related python library that is based on Flask. The default dash app will run a Flask server, which is as they stated, "not recommended for production environment". I have managed to find Twisted library which can do decent html handling. The problem is, I know how to use Twisted to host flask sites, but I do not know how to do the same for dash app. There is a nice library which integrates both flask and twisted together.
https://github.com/cravler/flask-twisted
To use it, one just need to use the following lines:
server = flask.Flask(__name__)
app = dash.Dash(__name__, server = server)
twisted = Twisted(server)
twisted.run(host='0.0.0.0',port=8050, debug=False)
Now, for learning purposes, I am trying to recreate the same functionality without flask-twisted. I tried my best to follow the source code in the module but still cannot recreate the same result. The page http://127.0.0.1:8082/my_flask/ is stuck at "Loading...". What did I do wrong?
if __name__ == '__main__':
resource = WSGIResource(reactor, reactor.getThreadPool(), server)
site = Site(WSGIRootResource(resource, {}))
server.run
root = Resource()
root.putChild(b'my_flask', site)
reactor.listenTCP(8082, Site(root))
reactor.run()
I'm following a mooc for building quickly a website in flask.
I'm using Cloud9 but i'm unable to watch my preview on it, i get an :
"Unable to load http preview" :
the code is really simple, here the views.py code
from flask import Flask, render_template
app = Flask(__name__)
# Config options - Make sure you created a 'config.py' file.
app.config.from_object('config')
# To get one variable, tape app.config['MY_VARIABLE']
#app.route('/')
def index():
return "Hello world !"
if __name__ == "__main__":
app.run()
And the preview screen, is what I get when I execute
python views.py
Thank you in advance
you need to make FLASK_APP environment variable, and flask application is not running like python views.py but flask run. Quick start
# give an environment variable, give the absolute path or relative
# path to you flask app, in your case it is `views.py`
export FLASK_APP=views.py
#after this run flask application
flask run
I faced the same problem. There is no way we can preview http endpoints directly. Although in AWS documentation they have asked to follow certain steps, but those too wont work. Only way is to access it using instance public address and exposing required ports. Read here for this.
Latest update: The problem had indeed to do with permission and user groups, today I learned why we do not simply use root for everything. Thanks to Jakub P. for reminding me to look into the apache error logs and thanks to domoarrigato for providing helpful insight and solutions.
What's up StackOverflow.
I followed the How To Deploy a Flask Application on an Ubuntu VPS tutorial provided by DigitalOcean, and got my application to successfully print out Hello, I love Digital Ocean! when being reached externally by making a GET request to my public server IP.
All good right? Not really.
After that, I edit the tutorial script and write a custom flask application, I test the script in my personal development environment and it runs without issue, I also test it on the DigitalOcean server by having it deploy on localhost and making another GET request.
All works as expected until I try to access it from my public DigitalOcean IP, now suddenly I am presented with a 500 Internal Server Error.
What is causing this issue, and what is the correct way to debug in this case?
What have I tried?
Setting app.debug = True gives the same 500 Internal Server Error without a debug report.
Running the application on the localhost of my desktop pc and DigitalOcean server gives no error, the script executes as expected.
The tutorial code runs and executed fine, and making a GET request to the Digital Ocean public IP returns the expected response.
I can switch between the tutorial application and my own application and clearly see that I am only getting the error wit my custom application. However the custom application still presents no issues running on localhost.
My code
from flask import Flask, request, redirect
from netaddr import IPNetwork
import os
import time
app = Flask(__name__)
APP_ROOT = os.path.dirname(os.path.abspath(__file__))
# Custom directories
MODULES = os.path.join(APP_ROOT, 'modules')
LOG = os.path.join(APP_ROOT, 'log')
def check_blacklist(ip_adress):
ipv4 = [item.strip() for item in open(MODULES + '//ipv4.txt').readlines()]
ipv6 = [item.strip() for item in open(MODULES + '//ipv6.txt').readlines()]
for item in ipv4 + ipv6:
if ip_adress in IPNetwork(item):
return True
else:
pass
return False
#app.route('/')
def hello():
ip_adress = request.environ['REMOTE_ADDR']
log_file = open(LOG + '//captains_log.txt', 'a')
with log_file as f:
if check_blacklist(ip_adress):
f.write('[ {}: {} ][ FaceBook ] - {} .\n'
.format(time.strftime("%d/%m/%Y"), time.strftime("%H:%M:%S"), request.environ))
return 'Facebook'
else:
f.write('[ {}: {} ][ Normal User ] - {} .\n'
.format(time.strftime("%d/%m/%Y"), time.strftime("%H:%M:%S"), request.environ))
return 'Normal Users'
if __name__ == '__main__':
app.debug = True
app.run()
The tutorial code:
from flask import Flask
app = Flask(__name__)
#app.route("/")
def hello():
return "Hello, I love Digital Ocean!"
if __name__ == "__main__":
app.run()
Seems like the following line could be a problem:
log_file = open(LOG + '//captains_log.txt', 'a')
if the path its looking for is: '/var/www/flaskapp/flaskapp/log//captains_log.txt'
that would make sense that an exception is thrown there. Possible that the file is in a different place, on the server, or a / needs to be removed - make sure the open command will find the correct file.
If captains_log.txt is outside the flask app directory, you can copy it in and chown it. if the txt file needs to be outside the directory then you'll have to add the user to the appropriate group, or open up permissions on the actual directory.
chown command should be:
sudo chown www:www /var/www/flaskapp/flaskapp/log/captains_log.txt
and it might be smart to run:
sudo chown -r www:www /var/www
I am having some problems understanding how a application written in python jsonrpc2 is related to a wgsi application.
I have a json rpc test application in a file called greeting.py
It is a simple test case
def hello(name=None,greeting=None):
# Print to stdout the greeting
result = "From jsonrpc you have: {greeting} , {name}".format(greeting=greeting,name=name)
# print result
# You can basically now return the string result
return result
Using the jsonrpc2 module I am able to POST json to this function which then returns a json response.
Sample post :
self.call_values_dict_webpost = dict(zip(["jsonrpc","method","id","params"],["2.0","greeting.hello","2",["Hari","Hello"]]))
Response returned as json:
u"jsonrpc": u"2.0", u"id": u"2", u"result": u"From jsonrpc you have: Hello , Hari"
I start the server with an entry point defined in the jsonrpc2 module which essentially does the following
from jsonrpc2 import JsonRpcApplication
from wsgiref.simple_server import make_server
app = JsonRpcApplication()
app.rpc.add_module("greeting")
httpd = make_server(host, port, app)
httpd.serve_forever()
I can currently run this jsonrpc2 server as a standalone "web app" and test it approproately.
I wanted to understand how to go from this simple function web app to a wsgi web app that reads and writes json without using a web framework such as flask or django ( which I know some of)
I am looking for whether there is a simple conceptual step that makes my function above compatible with a wsgi "callable" : or am I just better off using flask or django to read/receive json "POST" and write json response.
I don't know that particular module, but it looks like your app object is the WSGI application. All you do in that code is instantiate the app, then create a server for it via wsgiref. So instead of doing that, just point your real WSGI server - Apache/mod_wsgi, or gunicorn, or whatever - to that app object in exactly the same way as you would serve Flask or Django.