How to Save OpenVPN Username & Password

If you are using OpenVPN in a Linux platform through command line, it is always handy to be able to save the authentication information in a file and let openvpn use them. There are two ways you can do it.

First Method

First save the password in a file e.g auth.txt with two lines:

username
password

First line is for username and the second line is for password.

If you are using .ovpn files for configuration, open the .ovpn file and simply add the following:

auth-user-pass auth.txt

Now, your authentication would use the authentication given in that file

Second Method

You may add the auth-user-pass in the openvpn command line argument, but you have to make sure, this is passed after the --config. Here is an example

openvpn --config "your_file.ovpn" --auth-user-pass "auth.txt"

That should be enough.

How to Add Custom Sale Order Line in Odoo 12

There are two ways you can add custom sale order line in Odoo 12.

First Method

You can search the sale order first with the name or browse with the ID

sale_order = self.env['sale.order'].search([('name', '=', 'SO009')])

Now, you can see the sale order line IDs using the following:

sale_order.order_line

As this is a One2many relation, we need to use a tuple in the Odoo ORM write() method. Here is the list of data you can pass in a tuple to change data that has One2many or Many2many relation

Odoo ORM Documentation

You can now pass this as python dictionary for ‘order_line’ to sale.order of desired product as following:

sale_order_new.write({
'order_line': [
(0,0, {
'order_id': sale_order.id,
'product_id': 2003,
'price_unit': 3000.0,
'product_uom_qty': 2.0,
'name': ''
})
]
})

Second Method

In this method, you can simply define the order dictionary, and create a sale.order.line item with the order_id in reference. Here is an example

# define dictionary to add order_line
order_line_dict = { 'order_id' : 9, 'product_id': 2003, 'price_unit': 3000.0, 'product_uom_qty': 2.0, 'name': '' }

# search the order line for the sale order
sale_order_line = self.env['sale.order.line'].browse(9)

# create a new order line
sale_order_line.create(order_line_dict)

# print sale order lines
sale_order_line

Note

If you are doing/testing this on the Odoo Shell, then make sure to run the following after the changes to reflect on database:

self.env.cr.commit()

Odoo doesn’t call database cursor commit if you are coding on Odoo shell, it calls automatically though if you are doing it in a module. Just a friendly reminder!

Troubleshoot: -bash: fuser: command not found

If you are trying to use a command, fuser, that is used to identify process using lock file or socket file, and having the following error:

-bash: fuser: command not found

that means, your system doesn’t have the psmisc package installed. Usually, killall, fuser type of commands are under this package. CentOS 7 sometimes, do not install the package by default. To install it, run the following:

yum install psmisc -y

Once done, you should be able to use fuser command.

How To: Use SSH Password in a Script

You can obviously use RSA public/private keypair to access servers without password, although, sometimes, it may be desirable to use ssh password on a command line and run a remote command on another server. This can be done using a tool called ‘sshpass’. You can create a simple bash script using sshpass, that can help you monitor and control multiple servers from a single location.

How to use ssh password in script

First install sshpass:

# yum install sshpass -y

Once done, you can use sshpass command as following:

# sshpass -p "SSH_Password" ssh -o StrictHostKeyChecking=no SSH_Username@remote-ssh-server "yourcommand"

Just replace, the password, username, remote-ssh-server and your command with your desired setup, and viola!

Note: If yum says, the following:

No package sshpass* available.

then you would need to install epel repository to install sshpass. To install epel, run the following:

# yum install epel* -y

Programming: How To Check if an IP is Available or Not in Bash

How To Check if an IP is Available or Not in Bash

A quick trick I use is ‘ping’ command. PING will return 0 on success and 1 or above on failure while using it with -c 1 (Means only one ICMP packet). That makes it useful to use with a if condition shell code as following:

if ping -c 1 -w 5 192.168.2.1 >/dev/null
then
echo "IP Available"
else
echo "IP Not Available"

Programming: How to Check If A File Exists or Not in Bash Script

How to Check If A File Exists or Not in Bash Script

You can use if condition in bash script to do that. If conditions takes ‘-f’ to test if a file exists or not. Syntax would be the following:

$FILE = $1
if [ -f $FILE ]; then
echo "File Exists"
else
echo "File Do Not Exist"
endif

Now, if your script only demands to check if the file do not exist, you can use a unary operator for negate the boolean value as following:

$FILE = $1
if[ ! -f $FILE ]; then
echo "File Do Not Exist"
endif

 

How To: Restrict a Folder to Your IP Only

Sometimes, for development purposes, you may want to restrict access to the folder, only to your IP, and deny others from accessing that folder. One way to do that is to use htaccess rules. A common rule, could be denying all the users and allowing your IP. To find out, your IP, you may visit the following:

http://ifconfig.co

Note the IP it has reported. Open the folder that you want to protect. Find the .htaccess file under the folder (If no file available, create one) and add the following:

order deny,allow
deny from all
allow from <your IP goes here>

Replace the <your IP goes here> from the snippets with the IP you have noted from ifconfig.co. Now, your folder should be accessible only from your IP.

Programming: Laravel Error – Specified Key Was Too Long

A common error I have seen users reporting using Laravel, is the following:

SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes

The error actually happens because Laravel 5.5 assumes you have MySQL 5.7.7 or above. While on MySQL 5.7.7 the key size was increased than the older versions.

How to fix laravel Specified key was too long

To fix this, find the AppServiceProvider.php file under app/Providers folder, and add the following line before start of the class:

use Illuminate\Support\Facades\Schema;

Then, inside the boot() method under the class, add the following line:

Schema::defaultStringLength(191);

If you restart your laravel migration or the query, it should work fine now.

How To: Start a Screen Session and Run a Command at a Time

Sometimes, you may want to run a screen command in a remote server. That makes it necessary to run the command inside the screen session while starting it.

How to start a screen session and run a command in one line

# screen -d -m sh -c "yourcommand"

From the man page of Screen:

-d -m : Start screen in “detached” mode. This creates a new session but doesn’t attach to it. This is useful for system startup scripts.

sh -c: Starts a shell and runs a command for you.

 

How To: Install AutoSSL for Server Hostname – Cpanel Server

Starting from Cpanel 11.58, Cpanel is offering Free SSL, issued by ‘Cpanel INC’ for free of charge to the valid cpanel license owner. If you are using cpanel, login to your WHM >> Providers >> Enable Cpanel & from Options >> Check Allow AutoSSL to replace invalid or expiring non-AutoSSL certificates.

Now, running upcp should automatically install the free SSL for your cpanel server hostname. If it doesn’t, it is probably because your server IP and the hostname IP are resolving to wrong address. To understand and troubleshoot the problem, run the following script from command line:

# /usr/local/cpanel/bin/checkallsslcerts

This script checks and installs certificate for expired, invalid and self signed certificates for the server services. If you are seeing an error like the following:

[WARN] The system failed to acquire a signed certificate from the cPanel Store because of the following error: (XID 62hp6x) The system queried for a temporary file at “http://server91.mellowhost.com/.well-known/pki-validation/D92868E512FB02354F2498B94E67430B.txt”, but the web server responded with the following error: 404 (Not Found). A DNS (Domain Name System) or web server misconfiguration may exist.

It means, your hostname is resolving to the wrong IP. You would need to check if the hostname is resolving to an IP which has first virtualhost pointed to /var/www/html or not under /etc/apache2/conf/httpd.conf