Ttdfjt

I am trying to upload csv that I have exported from existing admin grid. Adding additional data as perticular columnwise in same csv. Howcan I upload/import that new .csv in admin and update data in already created custom admin-grid/table ?

I have finally done this by observer and event.
Admin field where I upload .csv file with format of current admin grid like name,certificationId.

Vendor/Module/etc/adminhtml/System.xml:

<section id="nasmsetting" translate="label" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
 <class>separator-top</class>
 <label>Nasm Setting</label>
 <tab>nasm</tab>
 <resource>Vendor_Module::nasm_config</resource>
 <group id="nasmgeneral" translate="label" type="text" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
 <label>General Settings</label>
 <field id="nasm_certification_file_upload" translate="label" type="MagentoConfigBlockSystemConfigFormFieldFile" sortOrder="2" showInDefault="1" showInWebsite="1" showInStore="1" >
 <label>Upload Latest NASM Table</label>
 <backend_model>MagentoConfigModelConfigBackendFile</backend_model>
 <upload_dir config="system" scope_info="1">nasmcustomers</upload_dir>
 <comment>Upload new NASM credentials</comment>
 </field>
 </group></section>

Now Create events.xml:
app/code/Vendor/Module/etc/adminhtml/events.xml
Here I have used "nasmsetting" as defined in system.xml. Which will change/update in admin and call this observer.So event name "admin_system_config_changed_section_nasmsetting"

<?xml version="1.0"?><config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
<event name="admin_system_config_changed_section_nasmsetting">
 <observer name="update_latest_nasm_table" instance="VendorModuleObserverUpdate" />
</event>

Observer where I read .csv and update table data:
app/code/Vendor/Module/Observer/Update.php

class Update implements ObserverInterface

protected $messageManager;

protected $_modelNasmFactory;

protected $csv;

public $_storeManager;

protected $_scopeConfig;

public function __construct(
 MagentoFrameworkMessageManagerInterface $messageManager,
 NasmFactory $modelNasmFactory,
 MagentoFrameworkFileCsv $csv,
 MagentoStoreModelStoreManagerInterface $storeManager,
 MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig
)
 
 $this->messageManager = $messageManager; 
 $this->_modelNasmFactory = $modelNasmFactory;
 $this->csv = $csv; 
 $this->_storeManager = $storeManager;
 $this->_scopeConfig = $scopeConfig;


/**
 * Below is the method that will fire whenever the event runs!
 *
 * @param Observer $observer
 */
public function execute(Observer $observer)

 try
 $model = $this->_modelNasmFactory->create();
 $storeScope = MagentoStoreModelScopeInterface::SCOPE_STORES;
 $uploadedCsvFilePath = $this->_scopeConfig->getValue("nasmsetting/nasmgeneral/nasm_certification_file_upload", $storeScope);

 $pubMediaUrl = $this->_storeManager->getStore()->getBaseUrl(MagentoFrameworkUrlInterface::URL_TYPE_MEDIA);
 $uploadedCsv = $pubMediaUrl."nasmcustomers/".$uploadedCsvFilePath;

 if($uploadedCsvFilePath != '')

 $handle = fopen($uploadedCsv, "r");

 $csv = array_map("str_getcsv", file($uploadedCsv,FILE_SKIP_EMPTY_LINES));
 array_shift($csv);

 // If NASM IDs exist truncate table
 // File uploaded will have IDs already in the database, not just new ones
 if (!empty($model)) 
 $connection = $model->getResource()->getConnection();
 $tableName = $model->getResource()->getMainTable();
 $connection->truncateTable($tableName);
 

 foreach ($csv as $i=>$row) 
 $customerName = $row[0]; //customername
 $certificationId = $row[1]; //certificationId
 $data = array('nasm_customer_name' => $customerName, 'nasm_code' => $certificationId);
 $model->setData($data);
 $model->save();
 
 
 catch(Exception $e) 

 $writer = new ZendLogWriterStream(BP . '/var/log/nasmlog.log');
 $logger = new ZendLogLogger();
 $logger->addWriter($writer);
 $error_message = "Unable to read csv file. Error: " . $e->getMessage() . '. See exception.log for full error log.';

 $this->messageManager->addError($error_message);
 $logger->info($e);