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<div style="text-align: center; color:#151B8D"><big style="font-weight: bold;"><big><big>
</big></big></big></div> <div style="text-align: center; color:#7E2217"><big style="font-weight: bold;"><big>
 程式碼解析
</big></big></div>
}}}
[[PageOutline]]
 = 零、前言 =

 * thrift 是透過非java的其他程式語言，直接對hbase 進行存取的中介函式庫
 * ''''' 此篇介紹的是如何用php透過 thrift 對 hbase 操作 '''''

 * 程式安裝測試方法已紀錄於： [wiki:waue/2010/0401 安裝編譯及測試 ]
 * 因此目錄結構為

 || hadoop || /opt/hadoop ||  
 || hbase || /opt/hbase ||  
 || 網頁根目錄 || /var/www/ ||  
 || hbase 的php碼目錄 || /var/www/hbase ||  
 || thrift php || /var/www/hbase/thrift ||  

 * 測試程式之前，請先確定
   * hbase , hadoop 都有正常運作中
   * $ bin/hbase thrift start  尚在執行

 = 一、php引用thrift lib =  

{{{
#!php
<?
$GLOBALS['THRIFT_ROOT'] = '/var/www/hbase/thrift';

require_once( $GLOBALS['THRIFT_ROOT'].'/Thrift.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/transport/TSocket.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/transport/TBufferedTransport.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/protocol/TBinaryProtocol.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/packages/Hbase/Hbase.php' );

$socket = new TSocket( 'localhost', 9090 );
$socket->setSendTimeout( 10000 ); // Ten seconds (too long for production, but this is just a demo ;)
$socket->setRecvTimeout( 20000 ); // Twenty seconds
$transport = new TBufferedTransport( $socket );
$protocol = new TBinaryProtocol( $transport );
$client = new HbaseClient( $protocol );
$transport->open();
?>
........
其他html 碼
<?
或是 下面提到的各式讀寫操作

?>
.......
<?
$transport->close();
?>
}}}

 * 所有的程式碼都必須包含這些引入函式庫、開啟關閉socket 的敘述

 = 二、各種對hbase的操作 =  

 == 2.1 列出hbase 裡的所有 table == 
{{{
#!php
<?
echo( "listing tables...\n" );
$tables = $client->getTableNames();
sort( $tables );
foreach ( $tables as $name ) {
  echo( "  found: {$name}\n" );
}
}
?>
}}}
 == 2.2 刪除table == 
{{{
#!php
<?
$name = "hbase table name";
if ($client->isTableEnabled( $name )) {
      echo( "    disabling table: {$name}\n");
      $client->disableTable( $name );
}
echo( "    deleting table: {$name}\n" );
    $client->deleteTable( $name );
}
?>
}}}
 == 2.3 新增table == 

 * 我們先定義columns 的物件結構如下
{{{
#!php
<?
$columns = array(
  new ColumnDescriptor( array(
    'name' => 'entry:',
    'maxVersions' => 10
  ) ),
  new ColumnDescriptor( array(
    'name' => 'unused:'
  ) )
);
?>
}}}

 * 將剛剛的column 放到table 內
{{{
#!php
<?
$t = "table name";
echo( "creating table: {$t}\n" );

try {
  $client->createTable( $t, $columns );
} catch ( AlreadyExists $ae ) {
  echo( "WARN: {$ae->message}\n" );
}

?>
}}}
 == 2.4 列出 table內的家族成員 family == 
{{{
#!php
<?
$t = "table name";
echo( "column families in {$t}:\n" );

$descriptors = $client->getColumnDescriptors( $t );
asort( $descriptors );
foreach ( $descriptors as $col ) {
  echo( "  column: {$col->name}, maxVer: {$col->maxVersions}\n" );
}
?>
}}}
 == 2.5 寫入資料 == 
{{{
#!php
<?
$t = "table name";
$row = "row name"
$valid = "foobar-\xE7\x94\x9F\xE3\x83\x93";

$mutations = array(
  new Mutation( array(
    'column' => 'entry:foo',
    'value' => $valid
  ) ),
);

$client->mutateRow( $t, $row, $mutations );
?>
}}}

 == 2.6 讀取資料 == 
 === get  取得一個 column value ===
 * get  取得一個 column value 的用法

{{{
#!php
<?
$table_name = 't1';
$row_name = '1';
$fam_col_name = 'f1:c1';

	$arr = $client->get($table_name, $row_name , $fam_col_name);
	// $arr = array
	foreach ( $arr as $k=>$v  ) {
		// $k = TCell
		echo ("value = {$v->value} , <br>  "); 
		echo ("timestamp = {$v->timestamp}  <br>");
	}
}
?>
}}}
 ===  getRow 取得一整個row ===
 * getRow($tableName, $row) 用法
{{{
#!php
<?
$table_name = "table name";
$row_name = "row name";

$arr = $client->getRow($table_name, $row_name);
// $client->getRow return a array
foreach ( $arr as $k=>$TRowResult  ) {
		// $k = 0 ; non-use
		// $TRowResult = TRowResult
		printTRowResult($TRowResult);
}
?>
}}}

 ===  scan 一整個table ===

{{{
#!php
<?
$table_name = 't1';
$start_row = ""; // 從row 的起點開始
$family = array( "f1","f2","f3" );


$scanner = $client->scannerOpen( $table_name, $start_row , $family );
// $scanner 是一個遞增數字 for open socket
// scannerGet() 一次只抓一row，因此要用while迴圈不斷地抓
while (true ){
		$get_arr = $client->scannerGet( $scanner );
		// get_arr is an array

		if($get_arr == null) break;
		// 沒有回傳值代表已經沒有資料可抓，跳脫此無限迴圈

		foreach ( $get_arr as $TRowResult ){
			// $TRowResult = TRowResult
			echo ("	row = {$TRowResult->row} ; <br> ");
			$column = $TRowResult->columns;
			foreach ($column as $family_column=>$Tcell){
					echo ("family:column = $family_column ");
					// $family_column = family_column
					// $Tcell = Tcell
					echo ("	value = {$Tcell->value} ");
					echo (" timestamp = {$Tcell->timestamp}  <br>");
			}
		}
}
echo( "<br> ----------------- " );
echo( "<br> Scanner finished <br>" );
$client->scannerClose( $scanner );
?>
}}}

= 補充 =

 == TCell == 
{{{
#!php
<?
class TCell {
	static $_TSPEC;

	public $value = null;
	public $timestamp = null;

	public function __construct($vals=null) {
		if (!isset(self::$_TSPEC)) {
			self::$_TSPEC = array(
			1 => array(
          'var' => 'value',
          'type' => TType::STRING,
			),
			2 => array(
          'var' => 'timestamp',
          'type' => TType::I64,
			),
			);
		}
		if (is_array($vals)) {
			if (isset($vals['value'])) {
				$this->value = $vals['value'];
			}
			if (isset($vals['timestamp'])) {
				$this->timestamp = $vals['timestamp'];
			}
		}
	}
}
?>
}}}
 == TRowResult ==
{{{
#!php
<?
class TRowResult {
	static $_TSPEC;

	public $row = null;
	public $columns = null;

	public function __construct($vals=null) {
		if (!isset(self::$_TSPEC)) {
			self::$_TSPEC = array(
			1 => array(
          'var' => 'row',
          'type' => TType::STRING,
			),
			2 => array(
          'var' => 'columns',
          'type' => TType::MAP,
          'ktype' => TType::STRING,
          'vtype' => TType::STRUCT,
          'key' => array(
            'type' => TType::STRING,
			),
          'val' => array(
            'type' => TType::STRUCT,
            'class' => 'TCell',
			),
			),
			);
		}
		if (is_array($vals)) {
			if (isset($vals['row'])) {
				$this->row = $vals['row'];
			}
			if (isset($vals['columns'])) {
				$this->columns = $vals['columns'];
			}
		}
	}
}
?>
}}}