README

Exports Yii2 data provider models to file using batch iteration and temp file for reduce memory usage

Installation

The preferred way to install this extension is through composer.

Either run

php composer.phar require --prefer-dist charmer/yii2-dataexporter "*"

or add

"charmer/yii2-dataexporter": "*"

to the require section of your composer.json file.

Usage

Example web controller with action that returns file for download:

<?php

namespace app\controllers;

use app\models\Clients;
use charmer\dataexporter\Exporter;
use charmer\dataexporter\Writers\CsvWriter;
use yii\web\Controller;
use yii\data\ActiveDataProvider;

class TestController extends Controller
{
    public function actionTest()
    {
        //Create Exporter object
        $exporter = new Exporter();
        //Create temp file
        $exporter->initTmpFile();
        //Create writer for CSV file format
        $writer = new CsvWriter();
        //Headers for exporting columns, ['model attribute' => 'Label']
        //you can simply use Model::attributeLabels() if you want to export all fields
        //or just type only fields you need for export
        $headers = [
            'id' => '№',
            'first_name' => 'First Name',
            'last_name' => 'Last Name',
            'email' => 'E-Mail',
            'created_at' => 'Created at'
        ];
        
        //Set fields for export
        $writer->setFields($headers);
        
        //Set writer to exporter
        $exporter->setWriter($writer);

        //Create DataProvider for export
        $provider = new ActiveDataProvider([
            'query' => Clients::find(),
            'pagination' => [
                'pageSize' => 5,
            ],
        ]);

        //Set created data provider to exporter 
        $exporter->setDataProvider($provider);
        //Prepare for export
        $exporter->prepare();
        //Export
        $exporter->export();
        
        //Get temp file path
        $path = $exporter->getTmpFileMetaData()['uri'];
        
        //return file for download
        return Yii::$app->response->sendFile($path, 'export.csv');
    }
}

Using different file type writers

There are 3 default writers in this package: CSV, JSON and XML. All you need to change exported file format is create needed writer object:

$csvWriter = new CsvWriter();
$jsonWriter = new JsonWriter();
$xmlWriter = new XmlWriter();

All other operations are the same for both writers.

Create own writers

For creating you own writer you need to extend your custom writer class from charmer\dataexporter\Writers\BaseWriter and implement write(array $data) method:

<?php

namespace charmer\dataexporter\Writers;

class TsvWriter extends BaseWriter
{
    public function write(array $data)
    {
        $this->exportedCount++;
        $row = implode('\t', $data)
        fputs($this->tmpFile, $row."\n");
    }
}

You can use BaseWriter class properties:

• mixed $tmpFile - temp file for export data
• int $exportedCount - number of exported items in current moment
• int $totalCount - total count of exporting items (DataProvider::getTotalCount() value)

You can use BaseWriter class methods:

• public Writer::initWriter() - if this method exists in your writer, it will be called right before Writer::write()
• closeWriter() - if this method exists in your writer, it will be called right after Writer::write()
• public function writeHeader() - writes headers line (from $writer->setFields($headers);) of exported fields (for example, for CSV export)

Example of JsonWriter:

<?php

namespace charmer\dataexporter\Writers;

class JsonWriter extends BaseWriter
{
    //Writes opening array symbol "[" in the beginning of the JSON file
    public function initWriter()
    {
        fputs($this->tmpFile, '[');
    }

    //Writes closing array symbol "]" in the end of the JSON file
    public function closeWriter()
    {
        fputs($this->tmpFile, ']');
    }

    //Writes JSON-serialized data to file
    public function write(array $data)
    {
        fputs($this->tmpFile, json_encode($data));
        $this->exportedCount++;

        if ($this->exportedCount < $this->totalCount) {
            fputs($this->tmpFile, ',');
        }
    }
}

You can use other writer class as the example of using other Writer methods and properties