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configuring Nginx to run flask automatically with uwsgi

I am developing python programs and I have a flask file which runs them. Now I am trying to run flask automatically from Nginx and linking them with uWSGI. It's not working and getting stuck.
I followed this page.here is the link: https://vladikk.com/2013/09/12/serving-flask-with-nginx-on-ubuntu/
I have performed all the necessary steps and got 502 bad gateway error.
while executing
uswgi --ini /var/www/tg/tg_uswgi.ini
I am getting the following
[uSWGI] getting INI configuration from /var/www/tg/tg_uwsgi.ini
after this, I am not getting anything.when i run my server, it still gives me 502 Bad gateway.
this is my
tg_nginx.conf
server {
listen 80;
server_name localhost;
charset utf-8;
client_max_body_size 75M;
location / { try_files $uri #yourapplication; }
location #yourapplication {
include uwsgi_params;
uwsgi_pass unix:/var/www/tg/tg_uwsgi.sock;
}
}
this is my tg_uwsgi.ini
[uwsgi]
#application's base folder
base = /var/www/tg
#python module to import
app = fileforflk //fileforflk is my flask file which calls other python
//files
module = %(app)
home = %(base)/venv
pythonpath = %(base)
#socket file's location
socket = /var/www/demoapp/%n.sock
#permissions for the socket file
chmod-socket = 666
#the variable that holds a flask application inside the module imported at line #6
callable = app
#location of log files
logto = /var/log/uwsgi/%n.log
this is my flask file
from flask import Flask
import browser //python file the flask is calling
app = Flask(_name_)
#app.route('/test',methods= ['GET'])
def result():
return ("success")
if _name_ == '_main_':
app.run(host = '0.0.0.0',port=5000)
After getting INI configuration, the terminal is not showing anything and the server still returns bad gateway. please help me with this.

You should define:
socket = /var/www/demoapp/%n.sock
And :
uwsgi_pass unix:/var/www/tg/tg_uwsgi.sock;
should be matching. So for example, define:
socket = /var/www/tg/%n.sock
And :
sudo chown -R www-data:www-data /var/www/tg/
sudo chown -R www-data:www-data /var/log/uwsgi/

Flask+nginx+uwsgi: only serve url with nginx if flask doesn't have a route for it

nginx config for the server (the main nginx one is the default one on debian 9):
server {
listen 80;
server_name subdomain.domain.com;
include /etc/nginx/mime.types;
location /galleries {
autoindex on;
alias /srv/galleries/;
}
location / {
include uwsgi_params;
uwsgi_pass unix:/tmp/scraper.sock;
}
}
uwsgi config:
[uwsgi]
module = wsgi:app
master = true
processes = 5
socket = /tmp/scraper.sock
chmod-socket = 777
uid = www-data
gid = www-data
vacuum = true
die-on-term = true
plugins = python3
py-autoreload = 1
If I try creating a route for /galleries/whatever, ie like this:
#app.route("/galleries/whatever")
def test():
return "Hello"
I'll just see the indexed files inside /galleries/whatever through nginx instead of going through flask.
Is there a way for me to force nginx to only handle requests if flask returns 404? Alternatively, is there a better way for me to serve files while still having them available under those urls? Keep in mind the /galleries folder is pretty big and generated by another program.
I run the server with "uwsgi --ini server.ini" and nothing else.

A file exists in uwsgi and bottle, but a 404 error occurs

file organization
・/hoge/1/a/bottle.py ・/hoge/1/a/hoge.py ・/hoge/1/a/hoge.ini
/hoge/1/a.py Error displayed on the screen Display contents
Error: 404 Not Found
Sorry, the requested URL 'http://example.com/hoge/1/a.py' caused an error:
Not found: '/hoge/1/a.py'
/hoge/1/a.py
#!/usr/bin/python3.6 python
# -*- coding:utf-8 -*-
from bottle import route, run, default_app
#route('/')
def index():
return "Hello World!"
application = default_app()
/hoge/1/a.ini
[uwsgi]
uid = nginx
gid = nginx
socket = /var/run/uwsgi/app/%n.sock
chmod-socket = 777
chdir = /var/www/example.com/hoge/1
wsgi-file = /var/www/example.com/hoge/1/%n.py
file = %n.py
processes = 4
threads = 2
a.ini log
announcing my loyalty to the Emperor...

This is because bottle only serves URLs which match one of the #routes that have been set up for it. In this case the only route that is set up is /, so only http://example.com/ will work.

uwsgi + nginx + flask + emperor: (104: Connection reset by peer) while reading response header from upstream

I am running a flask application using uwsgi and using nginx to serve the content.
vassal ini file:
[uwsgi]
chdir = /var/www/html/PyNLP/
;emperor = /var/www/html/PyNLP/
module = nltk_endpoint:app
master = true
processes = 5
socket = /tmp/PyNLP.sock
virtualenv = /var/www/html/PyNLP/nltkenv
mount = /PyNLP=nltk_endpoint:app
chmod-socket = 666
uid = www-data
gid = www-data
vacuum = true
die-on-term = true
enable-threads = true
;harakiri = 300
;buffer-size=65535
The project is contained in /var/www/html/PyNLP and contains the file nltk_endpoint.py along with the above .ini file
Now, when I run it without emperor:
uwsgi --ini PyNLP.ini --manage-script-name
It seems to be working fine when I try to access this flask API via a postman POST request. The URL looks like:
http://myIP:81/PyNLP/spellCheck
The first part /PyNLP is the mount point for the flask application and the last part /spellCheck is an app route in the project:
#app.route("/spellCheck", methods=["POST"])
def spellCheck():
req = request.get_json()
resp = jsonify(spell_check(req['text']))
return resp
The nginx config looks like:
location = /PyNLP { rewrite ^ /PyNLP/; }
location /PyNLP { try_files $uri #PyNLP; }
location #PyNLP {
# First attempt to serve request as file, then
# as directory, then fall back to displaying a 404.
#try_files $uri $uri/ =404;
include uwsgi_params;
uwsgi_pass unix:/tmp/PyNLP.sock;
}
Without emperor this works just fine. But when I try to use:
uwsgi --emperor emperor/emperor.ini --manage-script-name
I get a 404 error for the url path on postman
Emperor ini file:
[uwsgi]
;emperor-tyrant = true
;emperor = %dvassals
;emperor-pidfile = %demperor.pid
;emperor-stats = %demperor.stat.sock
;vassals-include = %dvassals-default.ini
;touch-logrotate = %p
;touch-reload = %p
;touch-reload = %dvassals-default.ini
;log-date = true
;log-truncate = true
;logto =
emperor = /var/www/html/PyNLP/
;chdir = /var/www/html/PyNLP/
;mount = /PyNLP=nltk_endpoint:app
;buffer-size=65535
uid = www-data
gid = www-data
vacuum = true
die-on-term = true
uwsgi log for this request was :
[pid: 9812|app: 0|req: 1/1] 111.125.198.234 () {48 vars in 841 bytes} [Tue Jan 23 10:49:17 2018] POST /PyNLP/spellCheck => generated 233 bytes in 5 msecs (HTTP/1.1 404) 2 headers in 72 bytes (1 switches on core 0)announcing my loyalty to the Emperor...
and nginx/error.log as :
*43 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 111.125.198.234, server: _, request: "POST /PyNLP/spellCheck HTTP/1.1", upstream: "uwsgi://unix:/tmp/PyNLP.sock:", host: "XX.XX.XX.XX:81"
Similar questions on stackoverflow suggested either to change buffer-size in ini files, which did not help as well as to verify if post body is handled correctly, which I think is fine as well, since it worked with POST request just fine without emperor. I suspect it may be a mount or url path issue or a permission issue, but cant figure out why this wont work with emperor. Any ideas? Thanks in advance.

Serving flask app on subdirectory nginx + uwsgi

I am try to deploy flask on a sub directory on my website, this script is super light weight and doesn't need (actually it can't) to roll into the main project. How ever when I go to the end point, I get a 404 error from flask (can confirm that it is flask because the log shows activity). I am passing uwsgi_param SCRIPT_NAME /upload; and uwsgi_modifier1 30; in my nginx config file, but that doesn't seem to work. How can I get uwsgi to serve my flask application on an nginx sub location (subdir)?
Here is my nginx config (the /upload location is where the trouble is):
upstream django {
server app0.api.xyz.com:9002;
}
server {
listen 443;
ssl on;
ssl_certificate /etc/nginx/ssl/cert_chain.crt;
ssl_certificate_key /etc/nginx/ssl/api_xyz.key;
charset utf-8;
server_name dev.api.xyz.com;
location / {
uwsgi_pass django;
include /etc/nginx/uwsgi_params;
}
location /media {
alias /var/xyzdata;
}
location /upload {
include /etc/nginx/uwsgi_params;
uwsgi_pass unix:/var/sockets/upload.sock;
uwsgi_param SCRIPT_NAME /upload;
uwsgi_modifier1 30;
}
}
my uwsgi.ini file:
[uwsgi]
chdir = /home/ubuntu/uploadFlask
module = images
callable = app
socket = /var/sockets/upload.sock
master = true
processes = 10
vacuum = true
uid = www-data
gid = www-data
daemonize = /var/log/uploads/error.log
and finally my entire flask app:
import os
from flask import Flask, request, redirect, url_for,Response, jsonify
from werkzeug import secure_filename
import time
UPLOAD_FOLDER = '/var/xyzdata'
ALLOWED_EXTENSIONS = set(['txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif'])
app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.config['DEBUG'] = True
#app.route('/<user>', methods=['POST'])
def upload_file(user):
file = request.files['file']
if file:
file_id = str(time.time()).replace('.','_')
filename = "{0}/images/{1}.jpg".format(user, file_id)
path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
d = os.path.dirname(path)
if not os.path.exists(d):
os.makedirs(d)
file.save(path)
return jsonify(physical_path=path, virtual_path=filename,
id=file_id)
#app.route('/delete/<user>/<id>/', methods=['POST'])
def delete_file(user, id):
pass
the point of this script is to upload images to my static server. My actual application sits on a separate server and thats why this can't sit there.
Basically what i want is to be able to go to dev.api.xyz.com/upload/123/ and hit upload_file. I'm expecting a 405 error in the browser, because it is restricted to POST. But I am getting a 404 error. Here is a sample output from the flask/uwsgi log:
[pid: 27900|app: 0|req: 4/5] 50.199.33.84 () {40 vars in 669 bytes} [Wed Jul 1 01:03:51 2015] GET /upload/things#things.com => generated 233 bytes in 0 msecs (HTTP/1.1 404) 2 headers in 72 bytes (1 switches on core 0)
So flask is getting hit but the url matching is not working. Thanks in advance for your help.

The best solution I've found so far would be using the mount option of uwsgi. In your config add the line
mount = /upload=<scriptname>
Solution courtesy of https://serverfault.com/questions/461946

Best and quick solution for me
location ~ /upload(/.*) {
include /etc/nginx/uwsgi_params;
uwsgi_pass unix:/var/sockets/upload.sock;
uwsgi_param PATH_INFO "$1";
}
Hope this can help you. cheers