Magento – Magento 2 Custom Module file Structure

You can install Magento 2 extension easily from any VCS (github or bitbcuket) if the module is packed with proper composer.json file.

For example, in order to install Easy Template Path Hints 2 extension, you just have to run two commands for installation:

composer config repositories.magesycho-magento2-easy-template-path-hints git git@github.com:MagePsycho/magento2-easy-template-path-hints.git
composer require magepsycho/magento2-easy-template-path-hints:dev-master

Explanation:

1> Registering the module git repository

composer config repositories.magesycho-magento2-easy-template-path-hints git git@github.com:MagePsycho/magento2-easy-template-path-hints.git

Composer config repository command syntax looks like:

composer config repositories.<unique-repo-name> <vcs-type> <vcs-url-https-or-sshl>

Composer will register a new repository to composer.json (under "repositories" node). Updated composer.json looks like:

{  
  "repositories": {
    "magesycho-magento2-easy-template-path-hints": {
      "type": "git",
      "url": "git@github.com:MagePsycho/magento2-easy-template-path-hints.git"
    }
  }
}

2> Registering the module package itself

composer require magepsycho/magento2-easy-template-path-hints:dev-master

Composer require command syntax:

composer require <vendor>/<package>:dev-<branch>

This will add new dependent package under node “require” as:

{
  "name": "magento/magento2ce",
  "description": "Magento 2 (Community Edition)",
  "type": "project",
  "require": {
    "magepsycho/magento2-easy-template-path-hints": "dev-master"
  }
}

and download the module from the repo.

And if you have extension zip file, just extract it and copy it to the app/code/ folder - as that simple.

Once the Module is installed, you can simply enable it using following commands:

php bin/magento module:enable MagePsycho_Easypathhints --clear-static-content
php bin/magento setup:upgrade

For this case,you need to create module which has a Helper.

At this helper class have a function getSoldQtyByProductId($productid).,which will give you no of sold products basic of order placed.

Helper class:

<?php
namespace [Vendorname]\[ModuleName]\Helper;
class Data extends \Magento\Framework\App\Helper\AbstractHelper
{
    protected $_reportCollectionFactory;    
     public function __construct(
        \Magento\Framework\App\Helper\Context $context,
        \Magento\Reports\Model\ResourceModel\Product\Sold\CollectionFactory  $reportCollectionFactory
    ) {
    $this->_reportCollectionFactory = $reportCollectionFactory;
        parent::__construct($context);
    }

    public function getSoldQtyByProductId($producID=null){
        $SoldProducts= $this->_reportCollectionFactory->create();
        $SoldProdudctCOl=$SoldProducts->addOrderedQty()->addAttributeToFilter('product_id', $producID);
        /* If does have any product id 
         * then return false
         */
        if(!$SoldProdudctCOl->count()):
                    return false;
        endif;
        echo $SoldProdudctCOl->getSelect()->__toString();

        $product = $SoldProdudctCOl
                        ->getFirstItem();

        return (int)$product->getData('ordered_qty');
    }
}

Now get Qty by below code:

$_helper = $this->_helper = $this->helper('[Vendorname]\[ModuleName]\Helper\Data');
$_helper->getSoldQtyByProductId($productId);