### Install Global npm Package

Source: https://docs.opalstack.com/topic-guides/nodejs

Example command to install a global package like PM2 after configuring the home directory environment.

```bash
npm install -g pm2
```

--------------------------------

### Install Project Dependencies

Source: https://docs.opalstack.com/topic-guides/nodejs

Navigate to the project directory and install dependencies using npm.

```bash
cd ~/apps/appname/projectname
npm install
```

--------------------------------

### Install Composer in Home Directory

Source: https://docs.opalstack.com/topic-guides/php

Downloads and installs the Composer dependency manager to the ~/bin directory.

```bash
cd ~
mkdir -p ~/bin
wget -O composer-setup.php https://getcomposer.org/installer
php composer-setup.php --install-dir=$HOME/bin --filename=composer
rm composer-setup.php
```

--------------------------------

### Install MariaDB Dependencies

Source: https://docs.opalstack.com/topic-guides/rails

Configure the environment and install MariaDB dependencies for Ruby.

```bash
cd ~/apps/myapp
source setenv
cd myproject
bundle install

```

--------------------------------

### Install Package in Virtual Environment

Source: https://docs.opalstack.com/topic-guides/python

Activates the environment and installs a package using pip.

```bash
source ~/apps/myapp/env/activate
pip install packagename
```

--------------------------------

### Running an Installation Script

Source: https://docs.opalstack.com/user-guide/applications

This command demonstrates how to execute a custom installation script for an application. Ensure you replace the placeholders with your application's UUID and name, and the correct path to your script.

```bash
cd ~/apps/name_of_app; 
~/.osscrc/XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXX \
  -i XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXX \
  -n name_of_app > ~/logs/apps/name_of_app/install.log

```

--------------------------------

### Install PostgreSQL Dependencies

Source: https://docs.opalstack.com/topic-guides/rails

Configure the environment and install PostgreSQL dependencies for Ruby.

```bash
cd ~/apps/myapp
source setenv
export PATH=/usr/pgsql-11/bin/:$PATH
cd myproject
bundle install

```

--------------------------------

### Install Gems in Rails Project

Source: https://docs.opalstack.com/topic-guides/rails

After preparing your shell environment and switching to your project directory, use `bundle install` to install gems specified in your project's `Gemfile`.

```bash
cd $PROJECTDIR

bundle install

```

--------------------------------

### Install PEAR via SSH

Source: https://docs.opalstack.com/topic-guides/php

Commands to download and execute the PEAR installer within a shell session.

```bash
cd ~
mkdir ~/tmp
wget https://pear.php.net/go-pear.phar
php go-pear.phar
```

--------------------------------

### PEAR Installation Layout Prompt

Source: https://docs.opalstack.com/topic-guides/php

The default file layout configuration displayed during the PEAR installation process.

```text
Below is a suggested file layout for your new PEAR installation.  To
change individual locations, type the number in front of the
directory.  Type 'all' to change all of them or simply press Enter to
accept these locations.

 1. Installation base ($prefix)                   : /home/username/pear
 2. Temporary directory for processing            : /home/username/tmp/pear/install
 3. Temporary directory for downloads             : /home/username/tmp/pear/install
 4. Binaries directory                            : /home/username/pear/bin
 5. PHP code directory ($php_dir)                 : /home/username/pear/share/pear
 6. Documentation directory                       : /home/username/pear/docs
 7. Data directory                                : /home/username/pear/data
 8. User-modifiable configuration files directory : /home/username/pear/cfg
 9. Public Web Files directory                    : /home/username/pear/www
10. System manual pages directory                 : /home/username/pear/man
11. Tests directory                               : /home/username/pear/tests
12. Name of configuration file                    : /home/username/.pearrc

1-12, 'all' or Enter to continue:
```

--------------------------------

### Install django-mcp-server

Source: https://docs.opalstack.com/user-guide/mcp

Command to install the Django MCP server package.

```bash
pip install django-mcp-server
```

--------------------------------

### Install Package Globally

Source: https://docs.opalstack.com/topic-guides/python

Installs a package in the home directory without using a virtual environment.

```bash
pip install --user packagename
```

--------------------------------

### Install pg gem for Ruby

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Install the 'pg' gem to enable Ruby applications to connect to PostgreSQL. Ensure your PATH is correctly configured before installation.

```bash
export PATH=/usr/pgsql-14/bin/:$PATH
gem install pg
```

--------------------------------

### Install psycopg for Python

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Install the psycopg library to enable Python applications to connect to PostgreSQL databases. Ensure your PATH is set correctly and activate your virtual environment.

```bash
export PATH=/usr/pgsql-14/bin/:$PATH
cd ~/apps/appname
source env/bin/activate
pip install psycopg
```

--------------------------------

### Configure Symlink Path

Source: https://docs.opalstack.com/topic-guides/symlinks

Example path format for a symlink application pointing to a directory in the user's home folder.

```text
/home/myuser/myfiles/
```

--------------------------------

### Install Javascript Packages with npm

Source: https://docs.opalstack.com/topic-guides/ghost

Install additional Javascript packages for your Ghost application using npm. Ensure you are in the correct directory and replace 'package_name' with the desired package.

```bash
source ~/apps/myapp/setenv
cd ~/apps/myapp/node
npm install package_name
```

--------------------------------

### Install virtualenv for Python 2

Source: https://docs.opalstack.com/topic-guides/python

Configures the environment and installs the virtualenv package required for Python 2.

```bash
export PATH=$HOME/.local/bin:$PATH
pip2.7 install --user -U pip==20.3.4
~/.local/bin/pip2.7 install --user virtualenv==20.15.1
```

--------------------------------

### Install Python Dependencies with Pip

Source: https://docs.opalstack.com/topic-guides/python

Install Python packages for your application using pip. Use 'pip install packagename' for individual packages or 'pip install -r requirements.txt' to install from a requirements file.

```bash
pip install packagename
```

```bash
pip install -r requirements.txt
```

--------------------------------

### Execute Single Command via SSH

Source: https://docs.opalstack.com/user-guide/server-access

Run a single command on your Opalstack server without starting an interactive session. This example reads the date from the server.

```bash
ssh myuser@opal1.opalstack.com date
```

--------------------------------

### Install MariaDB Dependencies for Django

Source: https://docs.opalstack.com/topic-guides/django

Enable the necessary development tools, activate your application's virtual environment, and install the mysqlclient package for MariaDB support. Replace 'myapp' with your application's name.

```bash
scl enable devtoolset-9 bash
source ~/apps/myapp/env/bin/activate
pip install mysqlclient
```

--------------------------------

### Install pg package for Node.js (Javascript)

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Install the 'pg' package for Node.js to allow Javascript applications to connect to PostgreSQL. Set your PATH and navigate to your project directory.

```bash
export PATH=/usr/pgsql-14/bin/:$PATH
npm install pg
```

--------------------------------

### Install Rails Dependencies

Source: https://docs.opalstack.com/topic-guides/rails

Install project dependencies using Bundler within the project directory.

```bash
cd /home/myuser/apps/myapp/yourproject
bundle install

```

--------------------------------

### Create SSH Directory and Files

Source: https://docs.opalstack.com/user-guide/server-access

These commands are used to create the necessary SSH directory and the `authorized_keys` file with the correct permissions on the server. This is typically done after logging in via SSH, for example, when configuring PuTTY.

```bash
mkdir ~/.ssh
chmod 700 ~/.ssh
touch ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys

```

--------------------------------

### Install PostgreSQL Dependencies for Django

Source: https://docs.opalstack.com/topic-guides/django

Activate your Django application's virtual environment and install the psycopg2 binary package for PostgreSQL support. Replace 'myapp' with your application's name.

```bash
source ~/apps/myapp/env/bin/activate
pip install "psycopg[binary]"
```

--------------------------------

### Install Gems in Application Environment

Source: https://docs.opalstack.com/topic-guides/rails

Use the `gem install` command after preparing your shell environment to add gems to the core Ruby on Rails software within your application's environment.

```bash
gem install name_of_gem

```

--------------------------------

### Connect via Python

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Requires the mysqlclient library installed in the environment.

```bash
source env/bin/activate
pip install mysqlclient

```

```python
import MySQLdb as mysql
conn = mysql.connect(host='localhost', user='mydbuser',
                     password='mydbpassword', database='mydb')

```

--------------------------------

### Configure Laravel Public Directory Path

Source: https://docs.opalstack.com/topic-guides/symlinks

Example path configuration for a Laravel project's public directory.

```text
/home/myuser/mysite/public/
```

--------------------------------

### PHP Configuration Prompt

Source: https://docs.opalstack.com/topic-guides/php

The prompt asking to modify the system php.ini file during installation.

```text
Would you like to alter php.ini </etc/php.ini>? [Y/n] :
```

--------------------------------

### Connect via Ruby

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Requires the mysql2 gem installed in the environment.

```bash
gem install mysql2

```

```ruby
require 'mysql2'
conn = Mysql2::Client.new(:host => "localhost", :username => "mydbuser",
                          :database => "mydb", :password => "mydbpassword")

```

--------------------------------

### Define Custom MCP Tools

Source: https://docs.opalstack.com/user-guide/mcp

Example of defining custom tools by extending the MCPToolset class.

```python
# myapp/mcp.py
from mcp_server import MCPToolset

class MyTools(MCPToolset):
    def ping(self, name: str = "world") -> dict:
        """Return a simple greeting."""
        return {"message": f"hello, {name}"}
```

--------------------------------

### Restart Gitea Application

Source: https://docs.opalstack.com/topic-guides/git

Commands to stop and then start your Gitea application after making configuration changes. Ensure you replace 'username' and 'appname' with your specific details.

```bash
/home/username/app/appname/stop
/home/username/app/appname/start
```

--------------------------------

### Connect via Javascript

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Requires the mysql package installed via npm.

```bash
npm install mysql

```

```javascript
var mysql = require('mysql');
var conn = mysql.createConnection({
    host: 'localhost',
    user: 'mydbuser',
    password: 'mydbpassword',
    database: 'mydb'
});
conn.connect();

```

--------------------------------

### Recreate Python 3 Virtual Environment and Install Dependencies

Source: https://docs.opalstack.com/user-guide/migrations

Use these shell commands to recreate a Python 3 virtual environment and reinstall project dependencies after migrating to AlmaLinux 9. This is for a Django project using a virtual environment named 'env'.

```shell
cd ~/apps/myapp

# recreate the env
mv env env.centos7
python3.10 -m venv env
source env/bin/activate
pip cache purge

# install uwsgi and your project dependencies
pip install uwsgi
pip install -r myproject/requirements.txt
```

--------------------------------

### Upgrade Installed Package

Source: https://docs.opalstack.com/topic-guides/python

Upgrades a package using the -U flag, either globally or within an active environment.

```bash
pip install --user -U packagename
```

```bash
pip install -U packagename
```

--------------------------------

### Clone Repository using Gitea SSH

Source: https://docs.opalstack.com/topic-guides/git

Example of cloning a repository from your Gitea instance using SSH authentication with your configured key. Replace 'myshelluser', 'gitea.mydomain.com', 'username', and 'reponame' accordingly.

```bash
git clone myshelluser@gitea.mydomain.com:username/reponame.git
```

--------------------------------

### Install Javascript Packages with npm (Build from Source)

Source: https://docs.opalstack.com/topic-guides/ghost

Re-install a Javascript package with the NPM_CONFIG_BUILD_FROM_SOURCE environment variable set to true, which can resolve binary compatibility issues.

```bash
source ~/apps/myapp/setenv
cd ~/apps/myapp/node
NPM_CONFIG_BUILD_FROM_SOURCE=true npm install package_name
```

--------------------------------

### Activate Python Environment

Source: https://docs.opalstack.com/topic-guides/django

Activate your application's Python environment via SSH before installing dependencies or running management commands.

```bash
cd ~/apps/appname
source env/bin/activate
```

--------------------------------

### Restart Python/uWSGI Application

Source: https://docs.opalstack.com/topic-guides/python

After modifying configuration files like uwsgi.ini, restart your application using its stop and start scripts to apply the changes.

```bash
/home/username/apps/appname/stop
```

```bash
/home/username/apps/appname/start
```

--------------------------------

### Reinstall Node.js Application Dependencies on AlmaLinux 9

Source: https://docs.opalstack.com/user-guide/migrations

Shell commands to reinstall Node.js application dependencies using npm after migrating to AlmaLinux 9. This example assumes Node.js v20 is used.

```shell
cd ~/apps/myapp/myproject
source scl_source enable nodejs20
npm install --force
```

--------------------------------

### Set up PostgreSQL Backup Directory and Script

Source: https://docs.opalstack.com/user-guide/postgresql-databases

These commands create necessary directories and files for automated PostgreSQL backups. They set up the database name, backup directories, and a placeholder script for the backup process. Ensure permissions are set correctly.

```bash
export DBNAME=mydb
mkdir -m 700 -p ~/.local/bin
mkdir -m 700 -p ~/.local/etc/psql_backups
mkdir -m 700 -p ~/backups/psql
touch ~/.pgpass
chmod 600 ~/.pgpass
touch ~/.local/bin/backup_$DBNAME
chmod 700 ~/.local/bin/backup_$DBNAME
```

--------------------------------

### Create Backup Directories and Files

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Run these commands to set up the necessary file structure and permissions for MariaDB backups. Ensure you replace 'mydb' with your actual database name.

```bash
export DBNAME=mydb
mkdir -m 700 -p ~/.local/bin
mkdir -m 700 -p ~/.local/etc/mariadb_backups
mkdir -m 700 -p ~/backups/mariadb
touch ~/.local/etc/mariadb_backups/$DBNAME.cnf
chmod 600 ~/.local/etc/mariadb_backups/$DBNAME.cnf
touch ~/.local/bin/backup_$DBNAME
chmod 700 ~/.local/bin/backup_$DBNAME

```

--------------------------------

### Prepare Shell Environment for Gem Management

Source: https://docs.opalstack.com/topic-guides/rails

Execute these commands to set up your shell environment for managing gems. Replace `myapp` and `myproject` with your actual application and project names.

```bash
cd ~/apps/myapp
source setenv

```

--------------------------------

### Install SQLite Binary for Django (Pre-Dec 2021)

Source: https://docs.opalstack.com/topic-guides/django

For Django applications installed prior to December 2021, install an updated SQLite binary package for Python using pip. Replace 'myapp' with your application's name.

```bash
source ~/apps/myapp/env/bin/activate
pip install pysqlite3-binary
```

--------------------------------

### Initialize Rails Application Environment

Source: https://docs.opalstack.com/topic-guides/rails

Navigate to the application directory and load the environment variables.

```bash
cd /home/myuser/apps/myapp
source setenv

```

--------------------------------

### Create a Subversion repository

Source: https://docs.opalstack.com/topic-guides/subversion

Initializes a new Subversion repository in the specified directory using the svnadmin tool.

```bash
svnadmin create ~/myrepo
```

--------------------------------

### Configure Ghost Site URL and Restart

Source: https://docs.opalstack.com/topic-guides/ghost

Set the site URL for your Ghost application and restart the service. Ensure you replace placeholders with your actual domain and app name.

```bash
source ~/apps/myapp/setenv
cd ~/apps/myapp/ghost
ghost config url https://domain.com
ghost restart
```

--------------------------------

### Activate Python Virtual Environment

Source: https://docs.opalstack.com/topic-guides/python

Activate your application's isolated Python environment before installing dependencies. This ensures packages are installed specifically for your application.

```bash
source /home/app_user/apps/app_name/env/bin/activate
```

--------------------------------

### Activate Node.js Environment

Source: https://docs.opalstack.com/topic-guides/nodejs

Commands to navigate to the application directory and enable the Node.js 20 environment.

```bash
cd ~/apps/appname
source scl_source enable nodejs20
```

--------------------------------

### Connect via Command Line Client

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Use the mysql command line tool after logging into an SSH session.

```bash
mysql -p -u mydbuser mydb

```

--------------------------------

### Update Gitea Start Script

Source: https://docs.opalstack.com/user-guide/migrations

Modify the Gitea application's start script to remove specific environment enabling commands, allowing it to run correctly on the new operating system.

```shell
/usr/sbin/daemonize -a -c $PWD -p $PIDFILE -e $HOME/logs/apps/gitea/gitea_error.log -o $HOME/logs/apps/gitea/gitea.log $PWD/gitea
```

--------------------------------

### Configure Global npm Tools

Source: https://docs.opalstack.com/topic-guides/nodejs

Commands to set up the npm prefix and update shell configuration to include global binaries in the PATH.

```bash
mkdir -p ~/.npm
echo 'prefix=~/.npm' >> ~/.npmrc
echo 'source scl_source enable nodejs20' >> ~/.bashrc
echo 'export PATH="$PATH:$HOME/.npm/bin"' >> ~/.bashrc
source ~/.bashrc
```

--------------------------------

### Configure Django SQLite Backend

Source: https://docs.opalstack.com/topic-guides/django

Include these lines in your `settings.py` before the `DATABASES` dictionary to use `pysqlite3` for SQLite.

```python
__import__('pysqlite3')
import os
import sys
sys.modules['sqlite3'] = sys.modules.pop('pysqlite3')
```

```python
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}
```

--------------------------------

### Connect via PHP

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Uses the mysqli extension to establish a database connection.

```php
$conn = new mysqli("localhost", "mydbuser", "mydbpassword", "mydb");

```

--------------------------------

### Restart Rails Instance

Source: https://docs.opalstack.com/topic-guides/rails

Create necessary temporary directories and execute the restart script.

```bash
mkdir -p /home/myuser/apps/myapp/yourproject/tmp/pids
mkdir -p /home/myuser/apps/myapp/yourproject/tmp/sockets
cp /home/myuser/apps/myapp/oldproject/tmp/pids/* /home/myuser/apps/myapp/yourproject/tmp/pids/
/home/myuser/apps/myapp/restart

```

--------------------------------

### Create Environment in App Directory

Source: https://docs.opalstack.com/topic-guides/python

Creates a virtual environment within a specific application directory.

```bash
python3 -m venv ~/apps/appname/env
```

--------------------------------

### Create Apache Password File

Source: https://docs.opalstack.com/topic-guides/php

Initializes a password file for HTTP authentication using the htpasswd utility.

```bash
cd ~/apps/myapp
htpasswd -c .htpasswd webuser
```

--------------------------------

### Run mbsync Migration

Source: https://docs.opalstack.com/user-guide/email

Execute the synchronization process to pull mail from the configured source to the destination.

```bash
mbsync --pull --all
```

--------------------------------

### Remove PHP Handler from .htaccess

Source: https://docs.opalstack.com/topic-guides/php

Example of a handler configuration that should be removed if the site is serving raw PHP source code.

```apache
<FilesMatch .php$>
    SetHandler php72-cgi
</FilesMatch>
```

--------------------------------

### Keyboard Shortcuts

Source: https://docs.opalstack.com/topic-guides/symlinks

List of keyboard shortcuts available for navigating the documentation.

```text
? | Open this help
n | Next page
p | Previous page
s | Search
```

--------------------------------

### Connect to PostgreSQL via Command Line

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Use this command to connect to your PostgreSQL database from the server's command line. You will be prompted for your database user password.

```bash
psql -U mydbuser mydb
```

--------------------------------

### Configure PostgreSQL Credentials for Backup

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Add this line to the `~/.pgpass` file to store your PostgreSQL connection details securely for automated backups. Replace 'mydbuser' and 'mydbpassword' with your actual credentials.

```bash
localhost:5432:mydb:mydbuser:mydbpassword
```

--------------------------------

### Configure Puma Project Directory

Source: https://docs.opalstack.com/topic-guides/rails

Update the project directory path in the Puma start/stop scripts.

```bash
PROJECTDIR=$HOME/apps/$APPNAME/yourproject

```

--------------------------------

### Set PHP Memory Limit

Source: https://docs.opalstack.com/topic-guides/php

Adjust the memory limit for your PHP application by setting the `memory_limit` directive in your `.user.ini` file. This example sets the limit to 256MB.

```ini
memory_limit = 256M
```

--------------------------------

### Configure uWSGI for Flask Application

Source: https://docs.opalstack.com/topic-guides/python

Modify the uwsgi.ini file to point to your Flask application. This example shows how to use the 'module' directive and 'touch-reload' for automatic restarts on file changes.

```ini
# adjust the following to point to your project
#wsgi-file = /home/username/apps/appname/myapp/wsgi.py
#touch-reload = /home/username/apps/appname/myapp/wsgi.py
module = flaskapp:app
touch-reload = /home/username/apps/appname/flaskapp/__init__.py
```

--------------------------------

### Set Maximum Upload File Size in PHP

Source: https://docs.opalstack.com/topic-guides/php

Configure the maximum file size for uploads by adding `post_max_size` and `upload_max_filesize` directives to your `.user.ini` file. This example sets the limit to 128MB.

```ini
post_max_size = 128M
upload_max_filesize = 128M
```

--------------------------------

### Configure SQLite Environment

Source: https://docs.opalstack.com/topic-guides/rails

Set the library path to use the system-maintained version of SQLite.

```bash
cd ~/apps/myapp
source setenv
export PATH=/usr/sqlite330/bin:$PATH
export LD_LIBRARY_PATH=/usr/sqlite330/lib:$LD_LIBRARY_PATH

```

--------------------------------

### Run Specific PHP Versions on Command Line

Source: https://docs.opalstack.com/topic-guides/php

Use these commands to execute specific PHP versions from the command line, as the default 'php' command may vary by server OS.

```bash
php56
```

```bash
php74
```

```bash
php80
```

```bash
php81
```

```bash
php82
```

```bash
php83
```

```bash
php84
```

```bash
php85
```

--------------------------------

### Configure SQLite Database for Django (Pre-Dec 2021)

Source: https://docs.opalstack.com/topic-guides/django

Configure the default database connection in your Django project's settings.py to use SQLite for older applications. This configuration assumes the pysqlite3-binary package has been installed.

```python
DATABASES = {
```

--------------------------------

### Set SQLite Library Path for Django

Source: https://docs.opalstack.com/topic-guides/django

Before running Django management commands with SQLite, set the LD_LIBRARY_PATH environment variable to ensure Django uses the correct SQLite version. This is for apps installed after December 2021.

```bash
export LD_LIBRARY_PATH=/usr/sqlite330/lib
```

--------------------------------

### Connect to PostgreSQL from Python

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Connect to your PostgreSQL database using the psycopg library in Python. Replace placeholder credentials with your actual database name, username, and password.

```python
import psycopg
conn = psycopg.connect(host='localhost', user='mydbuser',
                     password='mydbpassword', dbname='mydb')
```

--------------------------------

### Configure SQLite Database for Django (Post-Dec 2021)

Source: https://docs.opalstack.com/topic-guides/django

Configure the default database connection in your Django project's settings.py to use SQLite for applications installed after December 2021. This uses the standard Django SQLite configuration.

```python
    # then configure the engine and path to the DB here
    DATABASES = {
        'default': {
            'ENGINE': 'django.db.backends.sqlite3',
            'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
        }
    }
```

--------------------------------

### Configure PHP include_path

Source: https://docs.opalstack.com/topic-guides/php

The line to add to a .user.ini file to include the PEAR directory in the PHP search path.

```ini
include_path = .:/home/username/pear/share/pear
```

--------------------------------

### Import MariaDB Database

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Use the mysql command to import an existing SQL dump file into a database.

```bash
mysql -p -u mydbuser mydb < mydb.sql
```

--------------------------------

### Create Python 2 Virtual Environment

Source: https://docs.opalstack.com/topic-guides/python

Creates a virtual environment specifically for Python 2.7.

```bash
virtualenv --python=python2.7 envname
```

--------------------------------

### Configure PostgreSQL database.yml

Source: https://docs.opalstack.com/topic-guides/rails

Set the production database configuration for PostgreSQL.

```yaml
production:
  <<: *default
  adapter: postgresql
  database: your_database_name
  username: your_database_user_name
  password: your_database_user_password

```

--------------------------------

### Configure SSH Client for Gitea

Source: https://docs.opalstack.com/topic-guides/git

Configures your local SSH client to use the specific Gitea SSH key. Replace 'gitea.mydomain.com' with your Gitea site's domain and 'gitea_mydomain_com_rsa' with your key's filename.

```bash
Host gitea.mydomain.com
  IdentityFile ~/.ssh/gitea_mydomain_com_rsa
  IdentitiesOnly yes
```

--------------------------------

### Configure Django Static File Settings

Source: https://docs.opalstack.com/topic-guides/django

Set `STATIC_ROOT` and `STATIC_URL` in your `settings.py` to serve static content via Nginx.

```python
STATIC_ROOT = '/home/username/apps/mystatic'
STATIC_URL = '/static/'
```

--------------------------------

### Configure MariaDB Credentials

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Add these lines to your database credentials file. For AlmaLinux 9, include the 'no-tablespaces' parameter.

```ini
[client]
password='mydbpassword'

```

```ini
[client]
password='mydbpassword'
no-tablespaces

```

--------------------------------

### Connect to PostgreSQL from Javascript

Source: https://docs.opalstack.com/user-guide/postgresql-databases

Connect to your PostgreSQL database from a Javascript application using the 'pg' package. Configure the client with your database credentials and port.

```javascript
var pg = require('pg');
var conn = new pg.Client({
  user: 'mydbuser',
  host: 'localhost',
  database: 'mydb',
  password: 'mydbpassword',
  port: 5432,
})
conn.connect()
```

--------------------------------

### Configure MariaDB database.yml

Source: https://docs.opalstack.com/topic-guides/rails

Set the production database configuration for MariaDB.

```yaml
production:
  <<: *default
  adapter: mysql2
  database: your_database_name
  username: your_database_user_name
  password: your_database_user_password

```

--------------------------------

### Open authorized_keys with Nano Editor

Source: https://docs.opalstack.com/user-guide/server-access

This command opens the `authorized_keys` file in the `nano` text editor, allowing you to paste your public SSH key. Ensure the key is pasted as a single line.

```bash
nano -w ~/.ssh/authorized_keys

```

--------------------------------

### Establish SSH Tunnel for MariaDB

Source: https://docs.opalstack.com/user-guide/mariadb-databases

Use these commands on your local machine to forward a local port to the remote MariaDB server. Replace the user and host placeholders with your specific Opalstack credentials.

```bash
ssh myuser@opalN.opalstack.com -L 3306:127.0.0.1:3306 -N
```

```bash
ssh myuser@opalN.opalstack.com -L 3307:127.0.0.1:3306 -N
```

--------------------------------

### Execute IMAP Migration with imapsync

Source: https://docs.opalstack.com/user-guide/email

Run the transfer command without the dry-run flag to begin copying mail between servers.

```bash
imapsync --host1 OLD_MAILSERVER --ssl1 --user1 OLD_MAIL_USERNAME --passfile1 ./oldpasswd.txt \
    --host2 NEW_MAILSERVER --ssl2 --user2 NEW_MAILBOX --passfile2 ./newpasswd.txt
```

--------------------------------

### Activate Virtual Environment

Source: https://docs.opalstack.com/topic-guides/python

Activates a virtual environment for interactive use.

```bash
source envname/bin/activate
```

--------------------------------

### Configure SQLite database.yml

Source: https://docs.opalstack.com/topic-guides/rails

Set the production database configuration for SQLite.

```yaml
production:
  <<: *default
  adapter: sqlite3
  database: db/production.sqlite3

```

--------------------------------

### Configure uWSGI for Django Project

Source: https://docs.opalstack.com/topic-guides/django

Adjust `uwsgi.ini` to point to your Django project's path and WSGI file for serving.

```ini
# adjust the following to point to your project
python-path = /home/username/apps/appname/newsite
wsgi-file = /home/username/apps/appname/newsite/newsite/wsgi.py
touch-reload = {appdir}/newsite/newsite/wsgi.py
```

--------------------------------

### Test IMAP Migration with imapsync

Source: https://docs.opalstack.com/user-guide/email

Perform a dry run to verify connectivity and authentication before executing a full mail transfer.

```bash
imapsync --dry --host1 OLD_MAILSERVER --ssl1 --user1 OLD_MAIL_USERNAME --passfile1 ./oldpasswd.txt \
    --host2 NEW_MAILSERVER --ssl2 --user2 NEW_MAILBOX --passfile2 ./newpasswd.txt
```

--------------------------------

### Upload SSH Key via SSH Command

Source: https://docs.opalstack.com/user-guide/server-access

Use this command to upload your public SSH key to the server if `ssh-copy-id` is not available. Ensure you replace 'myuser' and 'opal1.opalstack.com' with your actual username and hostname. You will be prompted for your shell user's password.

```bash
cat ~/.ssh/id_rsa.pub | ssh myuser@opal1.opalstack.com \
"mkdir ~/.ssh && chmod 700 ~/.ssh && touch ~/.ssh/authorized_keys && \
chmod 600 ~/.ssh/authorized_keys && cat >>  ~/.ssh/authorized_keys"

```