plotly dash: change default port - plotly-dash

Following plotly dash getting started guide but when trying to run python app.py get message:
OSError: [WinError 10013] An attempt was made to access a socket in a way forbidden by its access permissions
Seems the default address: http://127.0.0.1:8050/ is already being used. How can the default port be changed so I can get this to work?

As we can see in Dash.run_server method definition, port can be passed as parameter:
def run_server(self,
port=8050,
debug=True,
threaded=True,
**flask_run_options):
self.server.run(port=port, debug=debug, **flask_run_options)
So, if you need to use another port:
if __name__ == '__main__':
app.run_server(debug=True, port=8051) # or whatever you choose

Note that in Julia, you can change the port by specifying the port number in the run_server arguments without specifying "port=". For example,
run_server(app, "0.0.0.0", 8000, debug = true)

You can also set the environment variable PORT in your terminal before launching the Dash app:
https://github.com/plotly/dash/blob/c77912a3183adfccfd4ef84df91eca7fa9c7d543/dash/_configs.py#L34

In the place of port = 8050 type your own port number

I was running it on a Jupyter notebook, and all I had to do was go to runtime and select factory reset runtime, pip install all dependencies (like jupyter-dash), and I was good to go...

Related

Heroku SSL connection error unsupported protocol

I have been using Heroku for a while to host my Discord bot. It has been connecting to a MySQL database hosted on ClearDB successfully. However, very recently, whenever I use the bot and it tries to connect to the database, it throws this error:
2026 (HY000): SSL connection error: error:1425F102:SSL routines:ssl_choose_client_version:unsupported protocol
It has been working completely fine until now, and I haven't changed anything. For background, all I did was delete a pipeline and make my app a standalone app without any pipeline. Just in case this helps.
Is this because Heroku has been updated? How can I fix my bot? Let me know if you need any more information.
Any help is appreciated, and Thank You in advance!
EDIT:
Database connection code:
import mysql.connector
def create_conn():
conn = None
try:
conn = mysql.connector.connect(host="HOST",
database="DB",
user="USER",
password="PWD")
except Exception as e:
print(e)
return conn
def execute_query(query, params, fetchall=True):
conn = create_conn()
if conn:
cursor = conn.cursor()
cursor.execute(query % params)
try:
if fetchall:
results = cursor.fetchall()
else:
results = cursor.fetchone()
except:
results = None
conn.commit()
cursor.close()
conn.close()
return results
else:
return False
The database connection used to work, and still works when I run it on my testing machine, a raspberry pi.
EDIT 2:
requirements.txt:
aiohttp==3.6.3
async-timeout==3.0.1
attrs==20.3.0
CacheControl==0.12.6
cachetools==4.2.0
certifi==2020.12.5
cffi==1.14.4
chardet==3.0.4
click==7.1.2
cryptography==3.3.1
cssselect==1.1.0
cssutils==1.0.2
discord==1.0.1
discord-pretty-help==1.2.0
discord.py==1.6.0
emoji==0.6.0
Flask==1.1.2
google-api-core==1.24.1
google-api-python-client==1.12.8
google-auth==1.24.0
google-auth-httplib2==0.0.4
google-cloud-core==1.5.0
google-cloud-firestore==2.0.2
google-cloud-storage==1.35.0
google-crc32c==1.1.0
google-resumable-media==1.2.0
googleapis-common-protos==1.52.0
grpcio==1.34.0
gunicorn==20.0.4
httplib2==0.18.1
idna==2.8
importlib-metadata==3.3.0
itsdangerous==1.1.0
jeepney==0.6.0
Jinja2==2.11.2
keyring==21.8.0
lxml==4.6.2
MarkupSafe==1.1.1
msgpack==1.0.2
multidict==4.7.6
mysql-connector-python==8.0.22
numpy==1.19.4
pandas==1.1.5
premailer==3.7.0
proto-plus==1.13.0
protobuf==3.14.0
pyasn1==0.4.8
pyasn1-modules==0.2.8
pycparser==2.20
python-dateutil==2.8.1
python-dotenv==0.15.0
pytz==2020.4
requests==2.25.1
rsa==4.7
schedule==0.6.0
SecretStorage==3.3.0
six==1.15.0
typing-extensions==3.7.4.3
uritemplate==3.0.1
urllib3==1.26.2
Werkzeug==1.0.1
yagmail==0.14.245
yarl==1.5.1
zipp==3.4.0
Just in case you can turn of ssl by:
conn = mysql.connector.connect(host="HOST",
database="DB",
user="USER",
password="PWD",
ssl_disabled=True)
i'm not quite sure how to do this, but i'm pretty sure you have to disable SSL for it to work, hope this helps.
Clearly, you need to enforce an SSL connection between your app and MySQL.
If you are using ruby stack then follow the given options and your SSL error problem will be solved.
Download the CA, Client, and Private Key files from your ClearDB dashboard and place them in the root of the application’s filesystem.
Make sure you have OpenSSL installed, which you can find here for Unix/Linux/OS X and here for Windows.
*Due to the MySQL client library configuration used on Heroku, you will need to strip the password from the private key file, which can be done like this:
$ openssl rsa -in cleardb_id-key.pem -out cleardb_id-key-no-password.pem
You can now delete the cleardb_id-key.pem and rename cleardb_id-key-no-password.pem to cleardb_id-key.pem, which you will use with your app.
*Set the DATABASE_URL config variable with the value of your modified CLEARDB_DATABASE_URL, like this:
$ heroku config:add DATABASE_URL="mysql2://abc1223:dfk243#us-cdbr-east.cleardb.com/my_heroku_db?
sslca=cleardb-ca-cert.pem&sslcert=cleardb_id-cert.pem&sslkey=cleardb_id-key.pem&reconnect=true"
notice how we added the “reconnect=true” parameters to the end of the URL? This is so that your application will automatically reconnect to ClearDB in the event of a connection timeout.
From here, simply restart your application (if Heroku didn’t already do that for you), and as long as you specified the correct file names and paths to the certificates in your DATABASE_URL, your app will now connect via SSL to ClearDB.

MySQL login-path issues with clustercheck script used in xinetd

default: on
# description: mysqlchk
service mysqlchk
{
# this is a config for xinetd, place it in /etc/xinetd.d/
disable = no
flags = REUSE
socket_type = stream
type = UNLISTED
port = 9200
wait = no
user = root
server = /usr/bin/mysqlclustercheck
log_on_failure += USERID
only_from = 0.0.0.0/0
#
# Passing arguments to clustercheck
# <user> <pass> <available_when_donor=0|1> <log_file> <available_when_readonly=0|1> <defaults_extra_file>"
# Recommended: server_args = user pass 1 /var/log/log-file 0 /etc/my.cnf.local"
# Compatibility: server_args = user pass 1 /var/log/log-file 1 /etc/my.cnf.local"
# 55-to-56 upgrade: server_args = user pass 1 /var/log/log-file 0 /etc/my.cnf.extra"
#
# recommended to put the IPs that need
# to connect exclusively (security purposes)
per_source = UNLIMITED
}
/etc/xinetd.d #
It is kind of strange that script works fine when run manually when it runs using /etc/xinetd.d/ , it is not working as expected.
In mysqlclustercheck script, instead of using --user= and passord= syntax, I am using --login-path= syntax
script runs fine when I run using command line but status for xinetd was showing signal 13. After debugging, I have found that even simple command like this is not working
mysql_config_editor print --all >>/tmp/test.txt
We don't see any output generated when it is run using xinetd ( mysqlclustercheck)
Have you tried the following instead of /usr/bin/mysqlclustercheck?
server = /usr/bin/clustercheck
I am wondering if you could test your binary location with the linux which command.
A long time ago since this question was asked, but it just came to my attention.
First of all as mentioned, Percona Cluster Control script is called clustercheck, so make sure you are using the correct name and correct path.
Secondly, since the server script runs fine from command line, it seems to me that the path of mysql client command is not known by the xinetd when it runs the Cluster Control script.
Since the mysqlclustercheck script as it is offered from Percona, it uses only the binary name mysql without specifying the absolute path I suggest you do the following:
Find where mysql client command is located on your system:
ccloud#gal1:~> sudo -i
gal1:~ # which mysql
/usr/local/mysql/bin/mysql
gal1:~ #
then edit script /usr/bin/mysqlclustercheck and in the following line:
MYSQL_CMDLINE="mysql --defaults-extra-file=$DEFAULTS_EXTRA_FILE -nNE --connect-timeout=$TIMEOUT \
place the exact path of mysql client command you found in the previous step.
I also see that you are not using MySQL connection credentials for connecting to MySQL server. mysqlclustercheck script as it is offered from Percona, it uses User/Password in order to connect to MySQL server.
So normally, you should execute the script in the command line like:
gal1:~ # /usr/sbin/clustercheck haproxy haproxyMySQLpass
HTTP/1.1 200 OK
Content-Type: text/plain
Where haproxy/haproxyMySQLpass is the MySQL connection user/pass for HAProxy monitoring user.
Additionally, you should specify them to your script's xinetd settings like:
server = /usr/bin/mysqlclustercheck
server_args = haproxy haproxyMySQLpass
Last but not least, the signal 13 you are getting is because you try to write something in a script run by xinetd. If for example in your mysqlclustercheck you try to add a statement like
echo "debug message"
you probably going to see the broken pipe signal (13 in POSIX).
Finally, I had issues with this script using SLES 12.3 and I finally manage to run it not as 'nobody' but as 'root'.
Hope it helps

How to pass secure_auth to MySQL login via SQLalchemy

I'm working on the front end of a webapp, and my co-developer is using Pyramid and SQAlchemy. We've just moved from SQLite to MySQL. I installed MySQL 5.6.15 (via Homebrew) on my OS X machine to get the Python MySQLdb install to work (via pip in a virtualenv).
Because in MySQL >= 5.6.5 secure_auth is now ON by default I can only connect to the remote database (pre 5.6.5) with the --skip-secure-auth flag, which works fine in a terminal.
However, in the Python Pyramid code, it only seems possible to add this flag as an argument to create_engine(), but I can't find create_engine() in my co-dev's code, only the connection string below in an initialisation config file. He's not available, this isn't my area of expertise, and we launch next week :(
sqlalchemy.url = mysql+mysqldb://gooddeeds:deeds808letme1now#146.227.24.38/gooddeeds_development?charset=utf8
I've tried appending various "secure auth" strings to the above with no success. Am I looking in the wrong place? Has MySQLdb set secure_auth to ON because I'm running MySQL 5.6.15? If so, how can I change that?
If you are forced to use the old passwords (bah!) when using MySQL 5.6, and using MySQLdb with SQLAlchemy, you'll have to add the --skip-secure-auth to an option file and use URL:
from sqlalchemy.engine.url import URL
..
dialect_options = {
'read_default_file': '/path/to/your/mysql.cnf',
}
engine = create_engine(URL(
'mysql',
username='..', password='..',
host='..', database='..',
query=dialect_options
))
The mysql.cnf would contain:
[client]
skip-secure-auth
For Pyramid, you can do the following. Add a line in your configuration ini-file that holds the connection arguments:
sqlalchemy.url = mysql://scott:tiger#localhost/test
sqlalchemy.connect_args = { 'read_default_file': '/path/to/foo' }
Now you need to change a bit the way the settings are read and used. In the file that launches your Pyramic app, do the following:
def main(global_config, **settings):
try:
settings['sqlalchemy.connect_args'] = eval(settings['sqlalchemy.connect_args'])
except KeyError:
settings['sqlalchemy.connect_args'] = {}
engine = engine_from_config(settings, 'sqlalchemy.')
# rest of code..
The trick is to evaluate the string in the ini file which contains a dictionary with the extra options for the SQLAlchemy dialect.

redis.conf include: "Bad directive or wrong number of arguments"

I've created this config for redis [/etc/redis/map.conf]:
include /etc/redis/ideal.conf
port 11235
pidfile /var/run/redis-map.pid
logfile /var/log/redis/map.log
dbfilename map.rdb
As you can see, it includes /etc/redis/ideal.conf; this file actually exists and we have read permissions.
Also there is another file, slightly different; consider [/etc/redis/storage.conf]:
include /etc/redis/ideal.conf
pidfile /var/run/redis-storage.pid
port 8000
bind 192.168.0.3
logfile /var/log/redis/storage.log
dbfilename dump_storage.rdb
My problem is: I can launch redis-server with storage.conf (and everything works fine), but map.conf leads to the following error:
Reading the configuration file, at line 1
>>> 'include /etc/redis/ideal.conf'
Bad directive or wrong number of arguments
failed
Version of redis is 2.2.
Where did I go wrong?
Sorry guys.
I was using different instances of Redis.
Instance for storage.conf was launched by /usr/local/bin/redis-server, but map.conf launched by /usr/bin/redis-server; second one is broken.
Thank you anyway.

Frequent worker timeout

I have setup gunicorn with 3 workers, 30 worker connections and using eventlet worker class. It is set up behind Nginx. After every few requests, I see this in the logs.
[ERROR] gunicorn.error: WORKER TIMEOUT (pid:23475)
None
[INFO] gunicorn.error: Booting worker with pid: 23514
Why is this happening? How can I figure out what's going wrong?
We had the same problem using Django+nginx+gunicorn. From Gunicorn documentation we have configured the graceful-timeout that made almost no difference.
After some testings, we found the solution, the parameter to configure is: timeout (And not graceful timeout). It works like a clock..
So, Do:
1) open the gunicorn configuration file
2) set the TIMEOUT to what ever you need - the value is in seconds
NUM_WORKERS=3
TIMEOUT=120
exec gunicorn ${DJANGO_WSGI_MODULE}:application \
--name $NAME \
--workers $NUM_WORKERS \
--timeout $TIMEOUT \
--log-level=debug \
--bind=127.0.0.1:9000 \
--pid=$PIDFILE
On Google Cloud
Just add --timeout 90 to entrypoint in app.yaml
entrypoint: gunicorn -b :$PORT main:app --timeout 90
Run Gunicorn with --log-level debug.
It should give you an app stack trace.
Is this endpoint taking too many time?
Maybe you are using flask without asynchronous support, so every request will block the call. To create async support without make difficult, add the gevent worker.
With gevent, a new call will spawn a new thread, and you app will be able to receive more requests
pip install gevent
gunicon .... --worker-class gevent
The Microsoft Azure official documentation for running Flask Apps on Azure App Services (Linux App) states the use of timeout as 600
gunicorn --bind=0.0.0.0 --timeout 600 application:app
https://learn.microsoft.com/en-us/azure/app-service/configure-language-python#flask-app
WORKER TIMEOUT means your application cannot response to the request in a defined amount of time. You can set this using gunicorn timeout settings. Some application need more time to response than another.
Another thing that may affect this is choosing the worker type
The default synchronous workers assume that your application is resource-bound in terms of CPU and network bandwidth. Generally this means that your application shouldn’t do anything that takes an undefined amount of time. An example of something that takes an undefined amount of time is a request to the internet. At some point the external network will fail in such a way that clients will pile up on your servers. So, in this sense, any web application which makes outgoing requests to APIs will benefit from an asynchronous worker.
When I got the same problem as yours (I was trying to deploy my application using Docker Swarm), I've tried to increase the timeout and using another type of worker class. But all failed.
And then I suddenly realised I was limitting my resource too low for the service inside my compose file. This is the thing slowed down the application in my case
deploy:
replicas: 5
resources:
limits:
cpus: "0.1"
memory: 50M
restart_policy:
condition: on-failure
So I suggest you to check what thing slowing down your application in the first place
Could it be this?
http://docs.gunicorn.org/en/latest/settings.html#timeout
Other possibilities could be your response is taking too long or is stuck waiting.
This worked for me:
gunicorn app:app -b :8080 --timeout 120 --workers=3 --threads=3 --worker-connections=1000
If you have eventlet add:
--worker-class=eventlet
If you have gevent add:
--worker-class=gevent
I've got the same problem in Docker.
In Docker I keep trained LightGBM model + Flask serving requests. As HTTP server I used gunicorn 19.9.0. When I run my code locally on my Mac laptop everything worked just perfect, but when I ran the app in Docker my POST JSON requests were freezing for some time, then gunicorn worker had been failing with [CRITICAL] WORKER TIMEOUT exception.
I tried tons of different approaches, but the only one solved my issue was adding worker_class=gthread.
Here is my complete config:
import multiprocessing
workers = multiprocessing.cpu_count() * 2 + 1
accesslog = "-" # STDOUT
access_log_format = '%(h)s %(l)s %(u)s %(t)s "%(r)s" %(s)s %(b)s "%(q)s" "%(D)s"'
bind = "0.0.0.0:5000"
keepalive = 120
timeout = 120
worker_class = "gthread"
threads = 3
I had very similar problem, I also tried using "runserver" to see if I could find anything but all I had was a message Killed
So I thought it could be resource problem, and I went ahead to give more RAM to the instance, and it worked.
You need to used an other worker type class an async one like gevent or tornado see this for more explanation :
First explantion :
You may also want to install Eventlet or Gevent if you expect that your application code may need to pause for extended periods of time during request processing
Second one :
The default synchronous workers assume that your application is resource bound in terms of CPU and network bandwidth. Generally this means that your application shouldn’t do anything that takes an undefined amount of time. For instance, a request to the internet meets this criteria. At some point the external network will fail in such a way that clients will pile up on your servers.
If you are using GCP then you have to set workers per instance type.
Link to GCP best practices https://cloud.google.com/appengine/docs/standard/python3/runtime
timeout is a key parameter to this problem.
however it's not suit for me.
i found there is not gunicorn timeout error when i set workers=1.
when i look though my code, i found some socket connect (socket.send & socket.recv) in server init.
socket.recv will block my code and that's why it always timeout when workers>1
hope to give some ideas to the people who have some problem with me
For me, the solution was to add --timeout 90 to my entrypoint, but it wasn't working because I had TWO entrypoints defined, one in app.yaml, and another in my Dockerfile. I deleted the unused entrypoint and added --timeout 90 in the other.
For me, it was because I forgot to setup firewall rule on database server for my Django.
Frank's answer pointed me in the right direction. I have a Digital Ocean droplet accessing a managed Digital Ocean Postgresql database. All I needed to do was add my droplet to the database's "Trusted Sources".
(click on database in DO console, then click on settings. Edit Trusted Sources and select droplet name (click in editable area and it will be suggested to you)).
Check that your workers are not killed by a health check. A long request may block the health check request, and the worker gets killed by your platform because the platform thinks that the worker is unresponsive.
E.g. if you have a 25-second-long request, and a liveness check is configured to hit a different endpoint in the same service every 10 seconds, time out in 1 second, and retry 3 times, this gives 10+1*3 ~ 13 seconds, and you can see that it would trigger some times but not always.
The solution, if this is your case, is to reconfigure your liveness check (or whatever health check mechanism your platform uses) so it can wait until your typical request finishes. Or allow for more threads - something that makes sure that the health check is not blocked for long enough to trigger worker kill.
You can see that adding more workers may help with (or hide) the problem.
The easiest way that worked for me is to create a new config.py file in the same folder where your app.py exists and to put inside it the timeout and all your desired special configuration:
timeout = 999
Then just run the server while pointing to this configuration file
gunicorn -c config.py --bind 0.0.0.0:5000 wsgi:app
note that for this statement to work you need wsgi.py also in the same directory having the following
from myproject import app
if __name__ == "__main__":
app.run()
Cheers!
Apart from the gunicorn timeout settings which are already suggested, since you are using nginx in front, you can check if these 2 parameters works, proxy_connect_timeout and proxy_read_timeout which are by default 60 seconds. Can set them like this in your nginx configuration file as,
proxy_connect_timeout 120s;
proxy_read_timeout 120s;
In my case I came across this issue when sending larger(10MB) files to my server. My development server(app.run()) received them no problem but gunicorn could not handle them.
for people who come to the same problem I did. My solution was to send it in chunks like this:
ref / html example, separate large files ref
def upload_to_server():
upload_file_path = location
def read_in_chunks(file_object, chunk_size=524288):
"""Lazy function (generator) to read a file piece by piece.
Default chunk size: 1k."""
while True:
data = file_object.read(chunk_size)
if not data:
break
yield data
with open(upload_file_path, 'rb') as f:
for piece in read_in_chunks(f):
r = requests.post(
url + '/api/set-doc/stream' + '/' + server_file_name,
files={name: piece},
headers={'key': key, 'allow_all': 'true'})
my flask server:
#app.route('/api/set-doc/stream/<name>', methods=['GET', 'POST'])
def api_set_file_streamed(name):
folder = escape(name) # secure_filename(escape(name))
if 'key' in request.headers:
if request.headers['key'] != key:
return 404
else:
return 404
for fn in request.files:
file = request.files[fn]
if fn == '':
print('no file name')
flash('No selected file')
return 'fail'
if file and allowed_file(file.filename):
file_dir_path = os.path.join(app.config['UPLOAD_FOLDER'], folder)
if not os.path.exists(file_dir_path):
os.makedirs(file_dir_path)
file_path = os.path.join(file_dir_path, secure_filename(file.filename))
with open(file_path, 'ab') as f:
f.write(file.read())
return 'sucess'
return 404
in case you have changed the name of the django project you should also go to
cd /etc/systemd/system/
then
sudo nano gunicorn.service
then verify that at the end of the bind line the application name has been changed to the new application name