Release notes for the ArangoDB-PHP driver 3.3.x

Starting from release 3.3.1, the PHP driver has support for automatic failover, for

ArangoDB servers that are started in the active failover mode. This setup requires

using ArangoDB 3.3.

In order to use automatic failover from the PHP driver, simply change the "endpoint"

attribute of the connection options from a simple endpoint string into an array of

endpoint strings:

$connectionOptions = [

ConnectionOptions::OPTION_ENDPOINT => [ 'tcp://localhost:8531', 'tcp://localhost:8532', 'tcp://localhost:8530' ],

...

];

$connection = new Connection($connectionOptions);

instead of just

$connectionOptions = [

ConnectionOptions::OPTION_ENDPOINT => 'tcp://localhost:8530',

...

];

$connection = new Connection($connectionOptions);

Additionally, retrieving the endpoint value of `ConnectionOptions` will now always

return an array of endpoints. For the single-server case, the returned value will be

an array with the specified endpoint. When active failover is used, the result will

be an array with the specified endpoints or the endpoints found (added) at runtime.

For example, in

$options = [ ConnectionOptions::OPTION_ENDPOINT => 'tcp://127.0.0.1:8529' ];

$co = new ConnectionOptions($options);

print_r($co[ConnectionOptions::OPTION_ENDPOINT]);

This will now print an array (`[ 'tcp://127.0.0.1:8529' ]`) and not just the string

(`tcp://127.0.0.1:8529'). Client applications that retrieve the endpoint value via

the `ConnectionOptions` object and expect it to be a string should be adjusted to

pick the first value from the now-returned result array instead.

Using the port option for setting up `ConnectionOptions` and reading it back is now

deprecated and will not be useful when using different endpoints with different port

numbers.

For example, reading the `port` option here will provide just one of the specified

ports, so it should be avoided:

$options = [ ConnectionOptions::OPTION_ENDPOINT => [ 'tcp://127.0.0.1:8529', 'tcp://127.0.0.1:8530' ] ];

$co = new ConnectionOptions($options);

print_r($co[ConnectionOptions::OPTION_PORT]);

Release notes for the ArangoDB-PHP driver 3.2.x

- [Setting up failover](#setting_up_failover)

<a name="setting_up_failover"></a>

By default the PHP client will connect to a single endpoint only,

by specifying a string value for the endpoint in the `ConnectionOptions`,

e.g.

$connectionOptions = [

ArangoConnectionOptions::OPTION_ENDPOINT => 'tcp://127.0.0.1:8529'

];

To set up multiple servers to connect to, it is also possible to specify

an array of servers instead:

$connectionOptions = [

ConnectionOptions::OPTION_ENDPOINT => [ 'tcp://localhost:8531', 'tcp://localhost:8532', 'tcp://localhost:8530' ]

];

Using this option requires ArangoDB 3.3 or higher and the database running

in active failover mode.

The driver will by default try to connect to the first server endpoint in the

endpoints array, and only try the following servers if no connection can be

established. If no connection can be made to any server, the driver will throw

an exception.

As it is unknown to the driver which server from the array is the current

leader, the driver will connect to the specified servers in array order by

default. However, to spare a few unnecessary connection attempts to failed

servers, it is possible to set up caching (using Memcached) for the server list.

The cached value will contain the last working server first, so that as few

connection attempts as possible will need to be made.

In order to use this caching, it is required to install the Memcached module

for PHP, and to set up the following relevant options in the `ConnectionOptions`:

$connectionOptions = [

// memcached persistent id (will be passed to Memcached::__construct)

ConnectionOptions::OPTION_MEMCACHED_PERSISTENT_ID => 'arangodb-php-pool',

// memcached servers to connect to (will be passed to Memcached::addServers)

ConnectionOptions::OPTION_MEMCACHED_SERVERS => [ [ '127.0.0.1', 11211 ] ],

// memcached options (will be passed to Memcached::setOptions)

ConnectionOptions::OPTION_MEMCACHED_OPTIONS => [ ],

// key to store the current endpoints array under

ConnectionOptions::OPTION_MEMCACHED_ENDPOINTS_KEY => 'arangodb-php-endpoints'

// time-to-live for the endpoints array stored in memcached

ConnectionOptions::OPTION_MEMCACHED_TTL => 600

];

"description": "ArangoDB PHP client",

"keywords": ["database","ArangoDB","Arango","document store","NoSQL","multi-model","graph database","distributed"],

// // to use failover (requires ArangoDB 3.3 and the database running in active/passive failover mode)

// // it is possible to specify an array of endpoints as follows:

// ConnectionOptions::OPTION_ENDPOINT => [ 'tcp://localhost:8531', 'tcp://localhost:8532' ]

// // to use memcached for caching the currently active leader (to spare a few connection attempts

// // to followers), it is possible to install the Memcached module for PHP and set the following options:

// // memcached persistent id (will be passed to Memcached::__construct)

// ConnectionOptions::OPTION_MEMCACHED_PERSISTENT_ID => 'arangodb-php-pool',

// // memcached servers to connect to (will be passed to Memcached::addServers)

// ConnectionOptions::OPTION_MEMCACHED_SERVERS => [ [ '127.0.0.1', 11211 ] ],

// // memcached options (will be passed to Memcached::setOptions)

// ConnectionOptions::OPTION_MEMCACHED_OPTIONS => [ ],

// // key to store the current endpoints array under

// ConnectionOptions::OPTION_MEMCACHED_ENDPOINTS_KEY => 'arangodb-php-endpoints'

// // time-to-live for the endpoints array stored in memcached

// ConnectionOptions::OPTION_MEMCACHED_TTL => 600