Create transport from class which don't has prefix name Elastica\Transport

[Gasol]

Allow we store configuration in JSON format, and simply restore to in-memory array and pass to Elastica\Client.

[ruflin]

I don't fully understand this change yet. Can you share some more details and example on this?

[Gasol]

Assume we define configuration of Elastica in JSON format.

// config.json

{
    "servers": [
        {
            "host": "elasticsearch-1",
            "port": "9200",
            "transport": "ACME\Transport\Stream"
        }
    ],
    "timeout": "1s",
    "connectionStrategy": "RoundRobin"
}

We can simply call json_decode to get configuration in array structure, then pass it to constructor of Elastica\Client. If transport in configuration does not pre-defined in Elastica\Transport\AbstractTransport, We will get exception shows Invalid transportwithout this change.

For example:

<?php
$data = file_get_contents('/path/to/config.json');
$config = json_decode($data, true);
$client = new Elastica\Client($config);

[ruflin]

I'm kind of thinking if we should turn this around. Have the base assumption that $transport is the full class name, and only have as fall back the Elastica once. I would have to check where in our code we would have to adjust these paths.

[Gasol]

Maybe we could check whether namespace separator () exists or not? It means it could be FQCN or built-in transport of Elastica right?

[Gasol]

Check namespace seperator is bad idea, We should not assume that class has a namespace.

[ruflin]

Nice, I was never thinking of this use case. I left some minor comments in the PR. Could you also update the CHANGELOG.md?

[Gasol]

@ruflin I have updated this PR for adding changelog.

[ruflin]

@Gasol Thanks, merged.