Access AWS DynamoDB through simpler interface in PHP
This module, dynamodb-php-wrapper, allows you to access DynamoDB more easily through interfaces shown below.
Each interface is just a wrapper, so accepts same arguments original one does and you can get that information from the document provided by AWS if needed.
This section assumes that:
- There is a table 'User', which has hash key 'UserId' as Number.
- There is a table 'Friend', which has hash key 'UserId' as Number and range key 'FriendUserId' as Number.
First of all, DynamoDBWrapper needs to be instantiated like this:
<?php
require_once '/path/to/aws-autoloader.php'; // provided by AWS
require_once '/path/to/DynamoDBWrapper.php'; // this module
$ddb = new DynamoDBWrapper(array(
'key' => 'YOUR_KEY',
'secret' => 'YOUR_SECRET_KEY',
'region' => 'SOME_REGION',
'version' => 'latest'
));then, you can access DynamoDB through this instance.
get is a wrapper of GetItem and will be used like this:
<?php
$key = array(
'UserId' => 2,
);
$result = $ddb->get('User', $key);
/*
Array
(
[Name] => User2
[UserId] => 2
)
*/batchGet is a wrapper of BatchGetItem and will be used like this:
<?php
$keys = array(
array(
'UserId' => 2,
),
array(
'UserId' => 3,
),
);
$result = $ddb->batchGet('User', $keys);
/*
Array
(
[0] => Array
(
[Name] => User 2
[UserId] => 2
)
[1] => Array
(
[Name] => User 3
[UserId] => 3
)
)
*/batchGet can get more than 25 items by one call. This wrapper sends multiple requests to DynamoDb if needed, and merge them as a single result.
query is a wrapper of Query and will be used like this:
<?php
$keyConditions = array(
'UserId' => 2,
);
$result = $ddb->query('Friend', $keyConditions);
/*
Array
(
[0] => Array
(
[UserId] => 2
[FriendUserId] => 3
)
[1] => Array
(
[UserId] => 2
[FriendUserId] => 4
)
...
)
*/query can accept options as $options, such as Limit, ExclusiveStartKey, ScanIndexForward and IndexName. If you use SLI, IndexName must be included in options.
scan is a wrapper of Scan and will be used like this:
<?php
$filter = array(
'UserId' => array('GT', 1),
'FriendUserId' => array('IN', array(4, 5)),
);
$result = $ddb->scan('Friend', $filter);
/*
Array
(
[0] => Array
(
[UserId] => 2
[FriendUserId] => 4
)
[1] => Array
(
[UserId] => 2
[FriendUserId] => 5
)
...
)
*/count is a wrapper of Query with Select param as COUNT. This return the number of items query fetches and will be used like this:
<?php
$keyConditions = array(
'UserId' => 2,
);
$result = $ddb->count('Friend', $keyConditions);
// 5put is a wrapper of putItem and will be used like this:
<?php
$item = array(
'UserId' => 1,
'Name' => 'User N',
);
$result = $ddb->put('User', $item);
// true, if successIf operation needs to be conditional, you can specify the expectation like this:
<?php
$item = array(
'UserId' => 1,
'Name' => 'User 1',
);
$expected = array(
'UserId' => array('Exists' => false)
);
$result = $ddb->put('User', $item, $expected);
// false, if UserId = 1 existsbatchPut is a wrapper of BatchWriteItem with put requests and will be used like this:
<?php
$items = array(
array(
'UserId' => 2,
'Name' => 'User2',
),
array(
'UserId' => 3,
'Name' => 'User3',
),
);
$result = $ddb->batchPut('User', $items);
// true, if successIf the number of requests is more than 25, this module divides the requests and send them continuously until all of requests are completed.
update is a wrapper of UpdateItem and will be used like this:
<?php
$key = array(
'UserId' => 2,
);
$update = array(
'Name' => array('PUT', 'New User Name')
);
$result = $ddb->update('User', $key, $update);
/*
Array
(
[Name] => New User Name
)
*/If operation succeeded, the updated value will be returned. If operation needs to be conditional, you can specify the expectation as 3rd arg.
delete is a wrapper of DeleteItem and will be used like this:
<?php
$key = array(
'UserId' => 2,
'FriendUserId' => 4,
);
$result = $ddb->delete('Friend', $key);
/*
Array
(
[UserId] => 2
[FriendUserId] => 4
)
*/If operation succeeded, the deleted item will be returned.
batchDelete is a wrapper of BatchWriteItem with put requests and will be used like this:
<?php
$keys = array(
array(
'UserId' => 2,
'FriendUserId' => 3,
),
array(
'UserId' => 2,
'FriendUserId' => 4,
),
...
);
$result = $ddb->batchDelete('Friend', $keys);
// true, if successIf the number of requests is more than 25, this module divides the requests and send them continuously until all of requests are completed.
createTable is a wrapper of CreateTable and will be used like this:
<?php
$result = $ddb->createTable('User', 'UserId');
// Create a table 'User', which has a hash key 'UserId' as STRING.
$result = $ddb->createTable('User', 'UserId::N');
// Create a table 'User', which has a hash key 'UserId' as NUMBER.
$result = $ddb->createTable('Friend', 'UserId', 'FriendUserId');
// Create a table 'Friend', which has a hash key 'UserId' as STRING and a range key 'FriendUserId' as STRING.If LSI is needed, it can be added like this:
<?php
$options = array(
'LocalSecondaryIndexes' => array(
array('name' => "UserName",
'type' => 'S',
'projection_type' => 'KEYS_ONLY'
),
array('name' => "CreatedAt",
'type' => 'S',
'projection_type' => 'KEYS_ONLY'
)
)
);
$result = $ddb->createTable('Friend', 'UserId', 'FriendUserId', $options);
// Create a table 'Friend', which has a hash key 'UserId' as STRING and a range key 'FriendUserId' as STRING and Local Secondary Index 'UserName' and 'CreatedAt' as both STRING.After requested, it will wait for completion.