waue/2011/1107: Cassandra-PHP-Client-Library-exp.php

<?php

// the only file that needs including into your project
require_once 'Cassandra.php';

// list of seed servers to randomly connect to
// all the parameters are optional and default to given values
$servers = array(
    array(
  'host' => '127.0.0.1',
  'port' => 9160,
  'use-framed-transport' => true,
  'send-timeout-ms' => 1000,
  'receive-timeout-ms' => 1000
    )
);

// create a named singleton, the second parameter name defaults to "main"
// you can have several named singletons with different server pools
$cassandra = Cassandra::createInstance($servers);

// at any point in code, you can get the named singleton instance, the name
// again defaults to "main" so no need to define it if using single instance
$cassandra2 = Cassandra::getInstance();

// drop the example keyspace and ignore errors should it not exist
try {
    $cassandra->dropKeyspace('CassandraExample');
} catch (Exception $e) {}


// create a new keyspace, accepts extra parameters for replication options
// normally you don't do it every time
$cassandra->createKeyspace('CassandraExample');

// start using the created keyspace
$cassandra->useKeyspace('CassandraExample');

// if a request fails, it will be retried for this many times, each time backing
// down for a bit longer period to prevent floods; defaults to 5
$cassandra->setMaxCallRetries(5);

// create a standard column family with given column metadata
$cassandra->createStandardColumnFamily(
    'CassandraExample', // keyspace name
    'user',             // the column-family name
    array(              // list of columns with metadata
  array(
      'name' => 'name',
      'type' => Cassandra::TYPE_UTF8,
      'index-type' => Cassandra::INDEX_KEYS, // create secondary index
      'index-name' => 'NameIdx'
  ),
  array(
      'name' => 'email',
      'type' => Cassandra::TYPE_UTF8
  ),
  array(
      'name' => 'age',
      'type' => Cassandra::TYPE_INTEGER,
      'index-type' => Cassandra::INDEX_KEYS,
      'index-name' => 'AgeIdx'
  )
    )
    // actually accepts more parameters with reasonable defaults
);

// create a super column family
$cassandra->createSuperColumnFamily(
    'CassandraExample',
    'cities',
    array(
  array(
      'name' => 'population',
      'type' => Cassandra::TYPE_INTEGER
  ),
  array(
      'name' => 'comment',
      'type' => Cassandra::TYPE_UTF8
  )
    ),
    // see the definition for these additional optional parameters
    Cassandra::TYPE_UTF8,
    Cassandra::TYPE_UTF8,
    Cassandra::TYPE_UTF8,
    'Capitals supercolumn test',
    1000,
    1000,
    0.5
);

// lets fetch and display the schema of created keyspace
$schema = $cassandra->getKeyspaceSchema('CassandraExample');
echo 'Schema: <pre>'.print_r($schema, true).'</pre><hr/>';

// should we need to, we can access the low-level client directly
$version = $cassandra->getConnection()->getClient()->describe_version();
echo 'Version directly: <pre>'.print_r($version, true).'</pre><hr/>';

// if implemented, use the wrapped methods as these are smarter - can retry etc
$version = $cassandra->getVersion();
echo 'Version through wrapper: <pre>'.print_r($version, true).'</pre><hr/>';

// cluster is a pool of connections
$cluster = $cassandra->getCluster();
echo 'Cluster: <pre>'.print_r($cluster, true).'</pre><hr/>';

// you can ask the cluster for a connection to a random seed server from pool
$connection = $cluster->getConnection();
echo 'Connection: <pre>'.print_r($connection, true).'</pre><hr/>';

// access column family, using the singleton syntax
// there is shorter "cf" methid that is an alias to "columnFamily"
$userColumnFamily = Cassandra::getInstance()->columnFamily('user');
echo 'Column family "user": <pre>'.print_r($userColumnFamily, true).'</pre><hr/>';

// lets insert some test data using the convinience method "set" of Cassandra
// the syntax is COLUMN_FAMILY_NAME.KEY_NAME
$cassandra->set(
    'user.john',
    array(
  'email' => 'john@smith.com',
  'name' => 'John Smith',
  'age' => 34
    )
);

// when inserting data, it's ok if key name contains ".", no need to escape them
$cassandra->set(
    'user.jane.doe',
    array(
  'email' => 'jane@doe.com',
  'name' => 'Jane Doe',
  'age' => 24
    )
);

// longer way of inserting data, first getting the column family
$cassandra->cf('user')->set(
    'chuck', // key name
    array(   // column names and values
  'email' => 'chuck@norris.com',
  'name' => 'Chuck Norris',
  'age' => 24
    ),
    Cassandra::CONSISTENCY_QUORUM // optional consistency to use
    // also accepts optional custom timestamp and time to live
);

// lets fetch all the information about user john
$john = $cassandra->get('user.john');
echo 'User "john": <pre>'.print_r($john, true).'</pre><hr/>';

// since the jane key "jane.doe" includes a ".", we have to escape it
$jane = $cassandra->get('user.'.Cassandra::escape('jane.doe'));
echo 'User "jane.doe": <pre>'.print_r($jane, true).'</pre><hr/>';

// there is some syntatic sugar on the query of Cassandra::get() allowing you
// to fetch specific columns, ranges of them, limit amount etc. for example,
// lets only fetch columns name and age
$chuck = $cassandra->get('user.chuck:name,age');
echo 'User "chuck", name and age: <pre>'.print_r($chuck, true).'</pre><hr/>';

// fetch all solumns from age to name (gets all columns in-between too)
$chuck2 = $cassandra->get('user.chuck:age-name');
echo 'User "chuck", columns ago to name: <pre>'.print_r($chuck2, true).'</pre><hr/>';

// the range columns do not need to exist, we can get character ranges
$chuck3 = $cassandra->get('user.chuck:a-z');
echo 'User "chuck", columns a-z: <pre>'.print_r($chuck3, true).'</pre><hr/>';

// when performing range queries, we can also limit the number of columns
// returned (2); also the method accepts consistency level as second parameter
$chuck4 = $cassandra->get('user.chuck:a-z|2', Cassandra::CONSISTENCY_ALL);
echo 'User "chuck", columns a-z, limited to 2 columns: <pre>'.print_r($chuck4, true).'</pre><hr/>';

// the Cassandra::get() is a convinience method proxying to lower level
// CassandraColumnFamily::get(), no need to worry about escaping with this.
// column family has additional methods getAll(), getColumns(), getColumnRange()
// that all map to lower level get() calls with more appopriate parameters
$jane2 = $cassandra->cf('user')->get('jane.doe');
echo 'User "jane.doe", lower level api: <pre>'.print_r($jane2, true).'</pre><hr/>';

// we defined a secondary index on "age" column of "user" column family so we
// can use CassandraColumnFamily::getWhere() to fetch users of specific age.
// this returns an iterator that you can go over with foreach or use the
// getAll() method that fetches all the data and returns an array
$aged24 = $cassandra->cf('user')->getWhere(array('age' => 24));
echo 'Users at age 24: <pre>'.print_r($aged24->getAll(), true).'</pre><hr/>';

// if we know we are going to need to values of several keys, we can request
// them in a single query for better performance
$chuckAndJohn = $cassandra->cf('user')->getMultiple(array('chuck', 'john'));
echo 'Users "chuck" and "john": <pre>'.print_r($chuckAndJohn, true).'</pre><hr/>';
/*
// we can fetch a range of keys but this is predictable only if using an
// order preserving partitioner, Cassandra defaults to random one
// again as there may be more results than it's reasonable to fetch in a single
// query, an iterator is returned that can make several smaller range queries
// as the data is iterated
$usersAZ = $cassandra->cf('user')->getKeyRange('a', 'z');
echo 'Users with keys in range a-z: <pre>'.print_r($usersAZ->getAll(), true).'</pre><hr/>';

// find the number of columns a key has, we could also request for ranges
$chuckColumnCount = $cassandra->cf('user')->getColumnCount('chuck');
echo 'User "chuck" column count: <pre>'.print_r($chuckColumnCount, true).'</pre><hr/>';

// we can find column counts for several keys at once
$chuckJaneColumnCounts = $cassandra->cf('user')->getColumnCounts(array('chuck', 'jane.doe'));
echo 'User "chuck" and "jane.doe" column counts: <pre>'.print_r($chuckJaneColumnCounts, true).'</pre><hr/>';

// setting supercolumn values is similar to normal column families
$cassandra->set(
    'cities.Estonia',
    array(
  'Tallinn' => array(
      'population' => '411980',
      'comment' => 'Capital of Estonia',
      'size' => 'big'
  ),
  'Tartu' => array(
      'population' => '98589',
      'comment' => 'City of good thoughts',
      'size' => 'medium'
  )
    )
);

// fetch all columns of Tartu in Estonia of cities
$tartu = $cassandra->cf('cities')->getAll('Estonia', 'Tartu');
echo 'Super-column cities.Estonia.Tartu: <pre>'.print_r($tartu, true).'</pre><hr/>';

// we could also use the higher level Cassandra::get() to fetch supercolumn info
// we can still use the additional filters of columns
$tallinn = $cassandra->get('cities.Estonia.Tallinn:population,size');
echo 'Super-column cities.Estonia.Tallinn: <pre>'.print_r($tallinn, true).'</pre><hr/>';

// you can delete all the data in a column family using "truncate"
$cassandra->truncate('user');

// you may choose to drop an entire keyspace
$cassandra->dropKeyspace('CassandraExample');
*/
?>