permission denied error while creating a file in python flask on apache and mod_wsgi - mod-wsgi

Question

I am trying to create a csv file through python flask. The code works fine in localhost but gives a permission denied error when deployed on apache + mod_wsgi on aws ec2 instance.
#app.route('/downloadChats/<db_token>/<requestrange>/', methods = ['GET'])
def downloadChats(db_token, requestrange):
<fetch data from table>
try:
filename = str(time.time()).strip().split('.')[0] + '.csv'
df = pd.DataFrame(columns = ['sessionid', 'city', 'ipAddress', 'startTime', 'timestamp', 'name', 'mob_no'])
for sessid in sessionids:
df = df.append({'sessionid' : disp_json[sessid]['sessionid'], 'city' : disp_json[sessid]['city'], 'ipAddress' : disp_j$
df.to_csv(filename, index = False)
except Exception as msg:
print("Exception while writing csv file in downloadChats : " + str(msg))
return "<h1> THis service is unavailable currently, Please try later. </h1> "
return send_from_directory('/var/www/FlaskApps/chatbotApp/', filename, as_attachment=True)
The app configuration file is :
<VirtualHost *:80>
ServerName example1.example.com
ServerAdmin admin#mywebsite.com
WSGIScriptAlias / /var/www/FlaskApps/FlaskApps.wsgi
WSGIPassAuthorization On
<Directory /var/www/FlaskApps/chatbotApp/>
Order allow,deny
Allow from all
</Directory>
<Directory /var/www/FlaskApps/chatbotApp/static/>
Order allow,deny
Allow from all
</Directory>
ErrorLog ${APACHE_LOG_DIR}/error.log
LogLevel warn
CustomLog ${APACHE_LOG_DIR}/access.log combined
RewriteEngine on
RewriteCond %{SERVER_NAME} = example1.example.com
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI}
[END,NE,R=permanent]
</VirtualHost>
The wsgi config file is :
import sys
import logging
logging.basicConfig(stream=sys.stderr)
sys.path.insert(0,"/var/www/FlaskApps/chatbotApp/")
# home points to the home.py file
from home import app as application
application.secret_key = "somesecretsessionkey"
Error :
[Errno 13] Permission denied: '1518497209.csv'

Answer 1

You can't use a relative path name as the working directory of the process will not be where your code is. This, along with what you need to do is explained in the mod_wsgi documentation at:
http://modwsgi.readthedocs.io/en/develop/user-guides/application-issues.html#application-working-directory