Servir-Mekong/hydrafloodviewer

The steps are meant to turn a generic Ubuntu box into an Django server hosting the Hydrafloods viewer with PostgreSQL, Nginx, Gunicorn, Virtualenv and supervisor

The HYDRAFloods Viewer is a web application used to view flood map results from the HYDRAFloods processing package along with additional hydrologic variables.

Update system

sudo apt-get update
sudo apt-get -y upgrade
sudo apt-get clean

Install Admin Tools

sudo apt-get -y install unzip psmisc mlocate telnet lrzsz vim rcconf htop p7zip dos2unix curl
sudo apt-get clean
sudo apt-get -y install gcc
sudo apt-get clean
sudo apt-get -y install build-essential libssl-dev libffi-dev libxml2-dev libxslt1-dev
sudo apt-get clean
sudo apt-get -y install libtiff5-dev libjpeg8-dev zlib1g-dev libfreetype6-dev liblcms2-dev libwebp-dev tcl8.6-dev tk8.6-dev python-tk
sudo apt-get clean

Git

sudo apt-get -y install git-core
sudo apt-get clean

Postgres

sudo apt-get -y install postgresql postgresql-contrib libpq-dev python-psycopg2
sudo apt-get -y install postgis
sudo apt-get clean

creating the database and user

• switch to superuser postgres

sudo su - postgres

• Create user for the tool

createuser --interactive -P
# The following questions shall be asked
#Enter name of role to add: hydrafloodtool
#Enter password for new role: 
#Enter it again: 
#Shall the new role be a superuser? (y/n) n
#Shall the new role be allowed to create databases? (y/n) n
#Shall the new role be allowed to create more new roles? (y/n) n

• Now create database

# hydrafloodtool is the name of the database and hydrafloodtool is the owner
createdb --owner hydrafloodtool hydrafloodtool

• Logout

logout

Install Python Virtual Environment

sudo apt-get -y install python-virtualenv
sudo apt-get clean

Create a folder for the hydrafloodtool

sudo mkdir /home/hydrafloodtool

• grant permission

sudo chown -R -v your-user /your-folder

Now create a virtual env for the jrcfloodtool

virtualenv /home/hydrafloodtool/hydrafloodtool_env

Workon the virtual env we just created

source /home/hydrafloodtool/hydrafloodtool_env/bin/activate

Install Python and environment

sudo apt-get -y install python-dev
sudo apt-get clean
sudo apt-get -y install python-pip
sudo apt-get -y install python-pillow
sudo apt-get clean

Download the hydrafloodviewer from git

env GIT_SSL_NO_VERIFY=true git clone https://github.com/Servir-Mekong/hydrafloodviewer.git hydrafloodviewer
cd hydrafloodviewer/

Install dependencies from the requirements.txt

pip install -r requirements.txt

Install rabbitmq message broker

sudo apt-get -y install erlang
sudo apt-get -y install rabbitmq-server

Enable the RabbitMQ service

sudo service rabbitmq-server start

Check the status of the RabbitMQ server

sudo service rabbitmq-server status

For local development, you can start the celery as

celery -A hydrafloodviewer worker -l info

NB: This is recommended only for development. For production, we need to use it as service

Copy the settings.example.py in the hydrafloodviewer and rename it as settings.py

Make changes in the settings

1. Make changes in the database settings
2. ALLOWED_URL
3. Make a folder named credentials in the project path and copy client_secret.json and privatekey.json

Verify the server is running by

python manage.py runserver 0.0.0.0:8000
# To end Ctrl + C

Now migrate the database

python manage.py migrate

Install application server

pip install gunicorn

Check if gunicorn is running well by

gunicorn hydrafloodviewer.wsgi:application --bind 0.0.0.0:8001

Now make sh (or bash) script called outside from project to automate with gunicorn

cd ..
nano gunicorn_hydrafloodviewer.sh

Edit according to your environment

#!/bin/bash

NAME="hydrafloodviewer"                                   # Name of the application
DJANGODIR=/home/hydrafloodtool/hydrafloodviewer             # Django project directory
SOCKFILE=/home/hydrafloodtool/hydrafloodtool_env/run/gunicorn.sock # we will communicte using this unix socket
USER=ubuntu                                           # the user to run as
GROUP=ubuntu                                          # the group to run as
NUM_WORKERS=3                                         # how many worker processes should Gunicorn spawn;                                               # usually is NUM_OF_CPU * 2 + 1
DJANGO_SETTINGS_MODULE=hydrafloodviewer.settings          # which settings file should Django use
DJANGO_WSGI_MODULE=hydrafloodviewer.wsgi                  # WSGI module name
TIMEOUT=60
echo "Starting $NAME as `whoami`"

# Activate the virtual environment

cd $DJANGODIR
source /home/hydrafloodtool_env/bin/activate
export DJANGO_SETTINGS_MODULE=$DJANGO_SETTINGS_MODULE
export PYTHONPATH=$DJANGODIR:$PYTHONPATH

# Create the run directory if it doesn't exist

RUNDIR=$(dirname $SOCKFILE)
test -d $RUNDIR || mkdir -p $RUNDIR

# Start your Django Unicorn
# Programs meant to be run under supervisor should not daemonize themselves (do not use --daemon)

exec gunicorn ${DJANGO_WSGI_MODULE}:application \
  --name $NAME \
  --workers $NUM_WORKERS \
  --user=$USER --group=$GROUP \
  --timeout $TIMEOUT \
  --bind=unix:$SOCKFILE \
  --log-level=debug \
  --log-file=-

Now make this script executable

sudo chmod u+x gunicorn_hydrafloodviewer.sh

Now install supervisor

sudo apt-get -y install supervisor

Now create a supervisor conf file for the project

sudo nano /etc/supervisor/conf.d/hydrafloodviewer.conf

And add the following bash script

[program:hydrafloodviewer]
command = /home/hydrafloodtool/gunicorn_hydrafloodviewer.sh ; Command to start app
user = ubuntu                                         ; User to run as
stdout_logfile = /home/hydrafloodtool/logs/hydrafloodviewer_supervisor.log ; Where to write log messages
redirect_stderr = true                                ; Save stderr in the same log
environment=LANG=en_US.UTF-8,LC_ALL=en_US.UTF-8       ; Set UTF-8 as default encoding

Now create the required files and folder

mkdir -p /home/hydrafloodtool/logs/
touch /home/hydrafloodtool/logs/hydrafloodviewer_supervisor.log

Make supervisor reread configuration files

Check your Ubuntu version

lsb_release -a

For ubuntu 14.04

sudo supervisorctl reread
sudo supervisorctl update
sudo supervisorctl start jrcfloodtool

For ubuntu 16.04

sudo systemctl restart supervisor
sudo systemctl enable supervisor

Check status of supervisor

sudo supervisorctl status hydrafloodviewer
jrcfloodtool             RUNNING  pid 24768, uptime 0:00:10

Make a conf file for celery

sudo nano /etc/supervisor/conf.d/hydrafloodviewer-celery.conf

And add the following bash script

[program:jrcfloodtool-celery]
command=/home/hydrafloodtool/hydrafloodtool_env/bin/celery worker -A jrcfloodtool --loglevel=INFO
directory=/home/hydrafloodtool/hydrafloodviewer
user=ubuntu
numprocs=1
stdout_logfile=/home/hydrafloodtool/logs/celery.log
stderr_logfile=/home/hydrafloodtool/logs/celery.log
autostart=true
autorestart=true
startsecs=10

; Need to wait for currently executing tasks to finish at shutdown.
; Increase this if you have very long running tasks.
stopwaitsecs = 600

stopasgroup=true

; Set Celery priority higher than default (999)
; so, if rabbitmq is supervised, it will start first.
priority=1000

Now create the required log file

touch /home/hydrafloodtool/logs/celery.log

Start the service and check its status

Start the service

sudo supervisorctl reread
sudo supervisorctl update

Check status of celery

sudo supervisorctl status hydrafloodviewer-celery
jrcfloodtool-celery      RUNNING  pid 21768, uptime 0:00:10

Install nginx

sudo apt-get -y install nginx

Make a conf file for nginx

sudo nano /etc/nginx/sites-available/hydrafloodviewer.conf

Then add the following script to the conf file

upstream hydrafloodviewer_server {
  # fail_timeout=0 means we always retry an upstream even if it failed
  # to return a good HTTP response (in case the Unicorn master nukes a
  # single worker for timing out).
  server unix:/home/directory=/home/hydrafloodtool/hydrafloodviewer/run/gunicorn.sock fail_timeout=0;
}

server {

    listen   80;
    server_name <your domain name>;

    client_max_body_size 4G;
    
    keepalive_timeout 0;
    sendfile on;
    
    access_log /home/hydrafloodtool/logs/nginx-access.log;
    error_log /home/hydrafloodtool/logs/nginx-error.log;

    location /static/ {
        alias   /home/hydrafloodtool/hydrafloodviewer/static/;
    }

    location / {

        # an HTTP header important enough to have its own Wikipedia entry:
        #   http://en.wikipedia.org/wiki/X-Forwarded-For
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;


        # enable this if and only if you use HTTPS, this helps Rack
        # set the proper protocol for doing redirects:
        # proxy_set_header X-Forwarded-Proto https;

        # pass the Host: header from the client right along so redirects
        # can be set properly within the Rack application
        proxy_set_header Host $http_host;

        # we don't want nginx trying to do something clever with
        # redirects, we set the Host: header above already.
        proxy_redirect off;

        # set "proxy_buffering off" *only* for Rainbows! when doing
        # Comet/long-poll stuff.  It's also safe to set if you're
        # using only serving fast clients with Unicorn + nginx.
        # Otherwise you _want_ nginx to buffer responses to slow
        # clients, really.
        # proxy_buffering off;

        # Try to serve static files from nginx, no point in making an
        # *application* server like Unicorn/Rainbows! serve static files.
        if (!-f $request_filename) {
            proxy_pass http://hydrafloodviewer_server;
            break;
        }
    }

    # Error pages
    error_page 500 502 503 504 /500.html;
    location = /500.html {
        root /home/hydrafloodtool/hydrafloodviewer/static/;
    }
}

Make a soft link to the nginx conf

sudo ln -s /etc/nginx/sites-available/hydrafloodviewer.conf /etc/nginx/sites-enabled/hydrafloodviewer.conf

You can delete the default soft link in the sites-enabled as

sudo rm /etc/nginx/sites-enabled/default

start the nginx service

sudo service nginx start

Sometimes ngnix might not work, so consider restarting the service as well

sudo service nginx restart

see the status of the nginx service

sudo service nginx status

NB: make sure the application, script and services have necessary permission to run

You can change permissions as

sudo chown -R -v your-user /your-folder