DEV Community: Lucas Dasso

Launch git-fork app from WSL

Lucas Dasso — Fri, 25 Oct 2019 01:14:39 +0000

As a web developer, I usually work on a Mac at work, and on my Windows 10 PC at home.

This article descrieve how I mange to use the Windows Fork app from my WSL installation.

TL:DR

From WSL edit your ~/.bashrc file
Add the following alias:alias fork='/mnt/c/Windows/System32/cmd.exe /c "%USERPROFILE%\\AppData\Local\Fork\Fork.exe "$(wslpath -w -a .)'
Save your changes.
Restart the terminal, so the new alias become available.

How to use

From WSL, navigate to a project folder that use git.
Run the alias: fork.
On Windows, the Fork app will open an the project git will be selected for view.

Background

I use vscode and the integrated terminal to manage my projects (for example to run Gulp.js tasks).

And as I do prefer the Linux/Mac terminal better, I configured vscode to work with the WSL bash as default.

Now, and this is important, I made symbolic link between my Window installation Work folder at C:\Work\ and my WSL installation at /home/ubuntu/Work/ folder.
This make super easy to work with any of my project, regardless if I'm working from Windows or from WSL.

The problem with Fork and WSL

One tool I like a lot is the free git client Fork.

While I usually use git from between the vscode, or from the WSL terminal, I like Fork the best to visualize and manage my projects git branches.

Fork is available for Mac and Windows, but not for Linux. :(

And as I configured vscode to use WSL as the default bash, I was unable to launch Fork from the terminal in the current working folder, as I regulary can on Mac or Windows.

Or that is what I thought, at first. :)

"wslpath" to the rescue

wslpath is a WSL tool that converts WSL paths to Windows paths.

And since I already created a symbolic link for my Work folder under WSL, all what was left was just to find a way to launch Fork on Windows from the WSL terminal, and to pass the current working WSL folder path converted to a Windows path.

The first part was easy enough. You can launch any Windows app fro WSL using this command: /mnt/c/Windows/System32/cmd.exe /c [PATH TO THE WINDOWS .EXE FILE]

So to launch Fork I can use this command: /mnt/c/Windows/System32/cmd.exe /c "%USERPROFILE%\AppData\Local\Fork\Fork.exe.

The Windows variable %USERPROFILE% will be automatically replaced with your Windows User folder path (ex.: C:\Users\yourusername).

You can pass a path to Fork executable file to launch the app and to automatically open the git repository on that path.
On linux, the current folder path is represented by .. But passing this to the Fork executable on Windows means nothing. I needed a way to convert this to a full and absolute Windows path.

And that is what wslpath does!.

So the final command looks like this: /mnt/c/Windows/System32/cmd.exe /c "%USERPROFILE%\AppData\Local\Fork\Fork.exe "$(wslpath -w -a .)

I added two parameters.

The -w parameter translate from a WSL path to a Windows path.
And the -a parameter force result to absolute path format.

The final step is to add this working command as a fork alias on my WSL installation, on your [WLS] user .bashrc file.
From your WSL installation, edit the ~/.bashrc file and add the following line: alias fork='/mnt/c/Windows/System32/cmd.exe /c "%USERPROFILE%\AppData\Local\Fork\Fork.exe "$(wslpath -w -a .)'

The result is that I can use Fork transparently from. between my WSL installation. I love it!

Happy coding!!

Custom module configuration form for Drupal

Lucas Dasso — Fri, 16 Aug 2019 22:13:38 +0000

Recently I found my self in the need to add a configuration page to a custom module in Drupal 7.

This module was used to send daily email notification to the users, but settings like the recipient list email address were hardcoded in the code.

To update this list I was forced to update the code repository and make a deploy on production. So this was not ideal.

So I put my self to the task to learn how to improve the custom module by adding its own configuration page.

Finally it only took a couple of hours to read the relevant documentation, implement the code, and perform the relevant tests.

TL;DR

You can skip directly to the documentation on this links:

Drupal 7 HowTos - Creating custom modules: https://www.drupal.org/docs/7/creating-custom-modules
- Preparing for a module configuration form: https://www.drupal.org/docs/7/creating-custom-modules/preparing-for-a-module-configuration-form
- Creating the configuration form: https://www.drupal.org/docs/7/creating-custom-modules/creating-the-configuration-form
- Validating the data: https://www.drupal.org/docs/7/creating-custom-modules/validating-the-data
Drupal 7 form API: https://api.drupal.org/api/drupal/developer%21topics%21forms_api_reference.html/7.x

Prerequisites

You will need a Drupal instance with a custom module already created for witch you also have access to the source code.

How to

All steps are to be applied on the .module file of your module, except for the step #2 that is to be applied on the .info file of the module.

1. Adding a new menu item

/**
 * Implements hook_menu().
 */
function my_custom_module_menu()
{
    $items = array();

    $items['admin/modules/my_custom_module'] = array(
        'title' => 'My Custom Module configuration',
        'description' => 'Configuration for My Custom Module',
        'page callback' => 'drupal_get_form',
        'page arguments' => array('my_custom_module_admin'),
        'access arguments' => array('administer site configuration'),
        'type' => MENU_NORMAL_ITEM,
    );

    return $items;
}

For this example the custom module name is my_custom_module, so the hook_menu function name must be my_custom_module_menu.

We add a new $items to the menu. The key value is the path to the main menu we want for this new page (in this example admin/modules/my_custom_module).
The page arguments value points to the function that will be used to populate the form (in this example my_custom_module_admi). We will build this function in the next step.
The access arguments value is used to determine who has access to this menu item.

2. Adding a configuration link in the module description

Adding a configuration link on the custom module description page is simple as adding this line to the .info module file:

configure = admin/modules/my_custom_module

This is the same menu path we already used on step #1.

3. Adding items to the form

function my_custom_module_admin($form, &$form_state)
{

    // EMAILS Fieldset
    $form['my_custom_module_settings__emails'] = array(
        '#type' => 'fieldset',
        '#title' => t('Email account settings'),
    );

    // From
    $form['my_custom_module_settings__emails']['my_custom_module_settings__emails__from'] = array(
        '#type' => 'textfield',
        '#title' => t('From address'),
        '#default_value' => variable_get('my_custom_module_settings__emails__from', false),
        '#description' => t('Email address to be used as FROM and Reply-To.'),
        '#required' => true,
    );
    // To
    $form['my_custom_module_settings__emails']['my_custom_module_settings__emails__to'] = array(
        '#type' => 'textarea',
        '#title' => t('To address'),
        '#default_value' => variable_get('my_custom_module_settings__emails__to', false),
        '#description' => t('Recipient email address. You can add multiple email addresses by separating them by a colon (,) character.'),
        '#required' => true,
    );

    return system_settings_form($form);
}

Adding items to the form is simple enough using the Drupal form API documentation.

In this example we can find a fieldset and insde two email fields. The first an input text field for the FORM address, and the second a textarea for multiple recipients email addresses.
In all the #default_value parameters we make use of the Drupal function variable_get to retrieve the last saved value of the field.
The name of the field is the one you specified on the $form array. So, for $form['my_custom_module_settings__emails']['my_custom_module_settings__emails__to'] the variable name will be my_custom_module_settings__emails__to.
The last line return system_settings_form($form); will take care to save the form values on submit.

4. Adding custom validating

function my_custom_module_admin_validate($form, &$form_state)
{

    $from = $form_state['values']['my_custom_module_settings__emails__from'];
    if (!filter_var($from, FILTER_VALIDATE_EMAIL)) {
        form_set_error('my_custom_module_settings__emails__from', t('You must enter a valid FROM email address.'));
    }

    $to = $form_state['values']['my_custom_module_settings__emails__to'];
    echo $to;
    $to = explode(',', $to);
    for ($i = 0; $i < count($to); $i++) {
        $address = trim($to[$i]);
        if (!filter_var($address, FILTER_VALIDATE_EMAIL)) {
            form_set_error('my_custom_module_settings__emails__to', t('You must enter a valid TO email address.'));
            break; //Exit the For/Loop on first error
        }
    }
}

While field parameters like '#required' will take care of basic validation like making a field requiered, some fields may require a more complex check up.

You can add a validation hook with the function name my_custom_module_admin_validate and add your own validations.

All form field values will be available inside the $form_state['values'].
You can validate multiple fields, and return errors individually by using the Drupal function form_set_error.

Thats all. Happy coding!

How to backup AWS Security Groups settings

Lucas Dasso — Thu, 15 Aug 2019 13:21:48 +0000

If, like me, you have to manage several Security Groups on your AWS account, you can make use of the describe-security-groups AWS CLI command for download them as a .json file for backup.

TL;DR

You can jump to the official AWS documentation for the describe-security-groups AWS CLI command on this link: https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-security-groups.html

Prerequisites

You will need to have the AWS CLI command line tool installed and configured on your system.

You can find the necessary information on this two links:

How to use

Open a terminal window on a local folder and run this command:
```
aws ec2 describe-security-groups --group-ids sg-123abcd4
```
You will need the ID of the Security Group you want the backup (in this example 'sg-123abcd4').
Done! You can now backup the newly created .json file with GIT or in any other way you want.

About the .json file

As a quick reference here is how the .json file looks:

{
    "SecurityGroups": [
        {
            "IpPermissionsEgress": [],
            "Description": "My security group",
            "IpPermissions": [
                {
                    "PrefixListIds": [],
                    "FromPort": 22,
                    "IpRanges": [
                        {
                            "CidrIp": "203.0.113.0/24"
                        }
                    ],
                    "ToPort": 22,
                    "IpProtocol": "tcp",
                    "UserIdGroupPairs": []
                }
            ],
            "GroupName": "MySecurityGroup",
            "OwnerId": "123456789012",
            "GroupId": "sg-903004f8",
        }
    ]
}