PHP hello world

Contoh kode ini adalah aplikasi "hello world" yang berjalan di PHP. Contoh ini menunjukkan cara menyelesaikan tugas-tugas berikut:

  • Menyiapkan autentikasi
  • Hubungkan ke instance Bigtable.
  • Buat tabel baru.
  • Tulis data ke tabel.
  • Baca kembali data.
  • Hapus tabel.

Menyiapkan autentikasi

Untuk menggunakan contoh Python di halaman ini dalam lingkungan pengembangan lokal, instal dan lakukan inisialisasi gcloud CLI, lalu siapkan Kredensial Default Aplikasi dengan kredensial pengguna Anda.

  1. Install the Google Cloud CLI.

  2. If you're using an external identity provider (IdP), you must first sign in to the gcloud CLI with your federated identity.

  3. To initialize the gcloud CLI, run the following command: 

    gcloud init

  4. If you're using a local shell, then create local authentication credentials for your user account: 

    gcloud auth application-default login

    You don't need to do this if you're using Cloud Shell.

    If an authentication error is returned, and you are using an external identity provider (IdP), confirm that you have signed in to the gcloud CLI with your federated identity.

Untuk informasi selengkapnya, lihat Set up authentication for a local development environment.

Menjalankan contoh

Contoh kode ini menggunakan paket library klien PHP untuk Cloud Bigtable dari Library Klien Google Cloud untuk PHP untuk berkomunikasi dengan Bigtable.

Untuk menjalankan program contoh ini, ikuti petunjuk untuk contoh di GitHub.

Menggunakan Library Klien Cloud dengan Bigtable

Aplikasi contoh terhubung ke Bigtable dan menunjukkan beberapa operasi dasar.

Memerlukan library klien

Contoh ini menggunakan class ApiException ApiCore serta sejumlah class di klien PHP untuk Bigtable.

use Google\ApiCore\ApiException;
use Google\Cloud\Bigtable\Admin\V2\Client\BigtableInstanceAdminClient;
use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\CreateTableRequest;
use Google\Cloud\Bigtable\Admin\V2\DeleteTableRequest;
use Google\Cloud\Bigtable\Admin\V2\GetTableRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Cloud\Bigtable\Admin\V2\Table;
use Google\Cloud\Bigtable\Admin\V2\Table\View;
use Google\Cloud\Bigtable\BigtableClient;
use Google\Cloud\Bigtable\Mutations;
use Google\Cloud\Bigtable\V2\RowFilter;

Menghubungkan ke Bigtable

Tetapkan variabel yang akan Anda gunakan dalam aplikasi, menggunakan Google Cloud project ID, ID instance Bigtable, dan ID tabel yang valid. Kemudian, buat objek BigtableInstanceAdminClient, BigtableTableAdminClient, dan BigtableClient baru yang Anda gunakan untuk terhubung ke Bigtable.

/** Uncomment and populate these variables in your code */
// $projectId = 'The Google project ID';
// $instanceId = 'The Bigtable instance ID';
// $tableId = 'The Bigtable table ID';

$instanceAdminClient = new BigtableInstanceAdminClient();
$tableAdminClient = new BigtableTableAdminClient();
$dataClient = new BigtableClient([
    'projectId' => $projectId,
]);

Membuat tabel

Periksa untuk melihat apakah tabel Anda sudah ada. Jika tidak, panggil metode createtable() untuk membuat objek Table. Tabel memiliki satu grup kolom yang menyimpan satu versi setiap nilai kolom.

$instanceName = $instanceAdminClient->instanceName($projectId, $instanceId);
$tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

// Check whether table exists in an instance.
// Create table if it does not exists.
$table = new Table();
printf('Creating a Table: %s' . PHP_EOL, $tableId);

try {
    $getTableRequest = (new GetTableRequest())
        ->setName($tableName)
        ->setView(View::NAME_ONLY);
    $tableAdminClient->getTable($getTableRequest);
    printf('Table %s already exists' . PHP_EOL, $tableId);
} catch (ApiException $e) {
    if ($e->getStatus() === 'NOT_FOUND') {
        printf('Creating the %s table' . PHP_EOL, $tableId);
        $createTableRequest = (new CreateTableRequest())
            ->setParent($instanceName)
            ->setTableId($tableId)
            ->setTable($table);

        $tableAdminClient->createtable($createTableRequest);
        $columnFamily = new ColumnFamily();
        $columnModification = new Modification();
        $columnModification->setId('cf1');
        $columnModification->setCreate($columnFamily);
        $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
            ->setName($tableName)
            ->setModifications([$columnModification]);
        $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);
        printf('Created table %s' . PHP_EOL, $tableId);
    } else {
        throw $e;
    }
}

Menulis baris ke tabel

Selanjutnya, gunakan array string salam untuk membuat beberapa baris baru untuk tabel. Untuk setiap ucapan, buat objek Mutations baru dan tambahkan ke entries menggunakan upsert(). Kemudian, tulis entri ke tabel menggunakan metode mutateRows() tabel.

$table = $dataClient->table($instanceId, $tableId);

printf('Writing some greetings to the table.' . PHP_EOL);
$greetings = ['Hello World!', 'Hello Cloud Bigtable!', 'Hello PHP!'];
$entries = [];
$columnFamilyId = 'cf1';
$column = 'greeting';
foreach ($greetings as $i => $value) {
    $rowKey = sprintf('greeting%s', $i);
    $rowMutation = new Mutations();
    $rowMutation->upsert($columnFamilyId, $column, $value, time() * 1000 * 1000);
    $entries[$rowKey] = $rowMutation;
}
$table->mutateRows($entries);

Menggunakan filter untuk membaca baris

Sebelum membaca data yang Anda tulis, buat filter untuk membatasi data yang ditampilkan Bigtable. Filter ini memberi tahu Bigtable untuk hanya menampilkan versi terbaru dari setiap nilai, meskipun tabel berisi versi lama yang belum dikumpulkan sampah.

Buat objek baris, lalu panggil metode readRow(), dengan meneruskan filter, untuk mendapatkan satu versi setiap kolom dalam baris tersebut.

printf('Getting a single greeting by row key.' . PHP_EOL);
$key = 'greeting0';
// Only retrieve the most recent version of the cell.
$rowFilter = (new RowFilter())->setCellsPerColumnLimitFilter(1);

$column = 'greeting';
$columnFamilyId = 'cf1';

$row = $table->readRow($key, [
    'filter' => $rowFilter
]);
printf('%s' . PHP_EOL, $row[$columnFamilyId][$column][0]['value']);

Memindai semua baris tabel

Panggil metode readRows(), teruskan filter, untuk mendapatkan semua baris dalam tabel. Karena Anda meneruskan filter, Bigtable hanya menampilkan satu versi setiap nilai.

$columnFamilyId = 'cf1';
$column = 'greeting';
printf('Scanning for all greetings:' . PHP_EOL);
$partialRows = $table->readRows([])->readAll();
foreach ($partialRows as $row) {
    printf('%s' . PHP_EOL, $row[$columnFamilyId][$column][0]['value']);
}

Menghapus tabel

Hapus tabel dengan metode deleteTable() klien admin.

try {
    printf('Attempting to delete table %s.' . PHP_EOL, $tableId);
    $deleteTableRequest = (new DeleteTableRequest())
        ->setName($tableName);
    $tableAdminClient->deleteTable($deleteTableRequest);
    printf('Deleted %s table.' . PHP_EOL, $tableId);
} catch (ApiException $e) {
    if ($e->getStatus() === 'NOT_FOUND') {
        printf('Table %s does not exists' . PHP_EOL, $tableId);
    } else {
        throw $e;
    }
}

Menggabungkan semuanya

Berikut contoh kode lengkap tanpa komentar.

<?php



require_once __DIR__ . '/../vendor/autoload.php';

if (count($argv) != 4) {
    return printf('Usage: php %s PROJECT_ID INSTANCE_ID TABLE_ID' . PHP_EOL, __FILE__);
}
list($_, $projectId, $instanceId, $tableId) = $argv;

use Google\ApiCore\ApiException;
use Google\Cloud\Bigtable\Admin\V2\Client\BigtableInstanceAdminClient;
use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\CreateTableRequest;
use Google\Cloud\Bigtable\Admin\V2\DeleteTableRequest;
use Google\Cloud\Bigtable\Admin\V2\GetTableRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Cloud\Bigtable\Admin\V2\Table;
use Google\Cloud\Bigtable\Admin\V2\Table\View;
use Google\Cloud\Bigtable\BigtableClient;
use Google\Cloud\Bigtable\Mutations;
use Google\Cloud\Bigtable\V2\RowFilter;



$instanceAdminClient = new BigtableInstanceAdminClient();
$tableAdminClient = new BigtableTableAdminClient();
$dataClient = new BigtableClient([
    'projectId' => $projectId,
]);

$instanceName = $instanceAdminClient->instanceName($projectId, $instanceId);
$tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

$table = new Table();
printf('Creating a Table: %s' . PHP_EOL, $tableId);

try {
    $getTableRequest = (new GetTableRequest())
        ->setName($tableName)
        ->setView(View::NAME_ONLY);
    $tableAdminClient->getTable($getTableRequest);
    printf('Table %s already exists' . PHP_EOL, $tableId);
} catch (ApiException $e) {
    if ($e->getStatus() === 'NOT_FOUND') {
        printf('Creating the %s table' . PHP_EOL, $tableId);
        $createTableRequest = (new CreateTableRequest())
            ->setParent($instanceName)
            ->setTableId($tableId)
            ->setTable($table);

        $tableAdminClient->createtable($createTableRequest);
        $columnFamily = new ColumnFamily();
        $columnModification = new Modification();
        $columnModification->setId('cf1');
        $columnModification->setCreate($columnFamily);
        $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
            ->setName($tableName)
            ->setModifications([$columnModification]);
        $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);
        printf('Created table %s' . PHP_EOL, $tableId);
    } else {
        throw $e;
    }
}

$table = $dataClient->table($instanceId, $tableId);

printf('Writing some greetings to the table.' . PHP_EOL);
$greetings = ['Hello World!', 'Hello Cloud Bigtable!', 'Hello PHP!'];
$entries = [];
$columnFamilyId = 'cf1';
$column = 'greeting';
foreach ($greetings as $i => $value) {
    $rowKey = sprintf('greeting%s', $i);
    $rowMutation = new Mutations();
    $rowMutation->upsert($columnFamilyId, $column, $value, time() * 1000 * 1000);
    $entries[$rowKey] = $rowMutation;
}
$table->mutateRows($entries);

printf('Getting a single greeting by row key.' . PHP_EOL);
$key = 'greeting0';
$rowFilter = (new RowFilter())->setCellsPerColumnLimitFilter(1);

$column = 'greeting';
$columnFamilyId = 'cf1';

$row = $table->readRow($key, [
    'filter' => $rowFilter
]);
printf('%s' . PHP_EOL, $row[$columnFamilyId][$column][0]['value']);

$columnFamilyId = 'cf1';
$column = 'greeting';
printf('Scanning for all greetings:' . PHP_EOL);
$partialRows = $table->readRows([])->readAll();
foreach ($partialRows as $row) {
    printf('%s' . PHP_EOL, $row[$columnFamilyId][$column][0]['value']);
}

try {
    printf('Attempting to delete table %s.' . PHP_EOL, $tableId);
    $deleteTableRequest = (new DeleteTableRequest())
        ->setName($tableName);
    $tableAdminClient->deleteTable($deleteTableRequest);
    printf('Deleted %s table.' . PHP_EOL, $tableId);
} catch (ApiException $e) {
    if ($e->getStatus() === 'NOT_FOUND') {
        printf('Table %s does not exists' . PHP_EOL, $tableId);
    } else {
        throw $e;
    }
}