InfluxDB response handlers

Thanks to GuzzleHTTP middleware infrastructure we can convert HTTP responses from InfluxDB in a more simple data structure, in the same way we can also manage query errors.

Convert your data structure

Actually the InfluxDB-PHP-SDK (by Corley) do not manage the JSON messages received from InfluxDB. That mean that you have to deal with this kind of data:

array(1) {
  'results' =>
  array(1) {
    [0] =>
    array(1) {
      'series' =>
      array(1) {
        ...
      }
    }
  }
}

If you prefere a more simple data structure, you can append response handlers to your GuzzleHTTP client in order to convert the InfluxDB response directly at runtime and obtain something more simple and readable

array(1) {
  'cpu' => array(2) {
    [0] => array(4) {
      'time' => string(30) "2015-09-09T20:42:07.927267636Z"
      'value1' => int(1)
      'value2' => int(2)
      'valueS' => string(6) "string"
    }
    [1] => array(4) {
      'time' => string(30) "2015-09-09T20:42:51.332853369Z"
      'value1' => int(2)
      'value2' => int(4)
      'valueS' => string(11) "another-one"
    }
  }
}

That is more simple to use than the InfluxDB default response

Append the response handler

During your GuzzleHTTP client setup just push the message_handler handler

use GuzzleHttp\HandlerStack;
use GuzzleHttp\Handler\CurlHandler;
use GuzzleHttp\Client as HttpClient;
use InfluxDB\Client;
use InfluxDB\Options;
use InfluxDB\Adapter\GuzzleAdapter;

$stack = new HandlerStack();
$stack->setHandler(new CurlHandler());
$stack->push(\InfluxDB\Handler\message_handler()); // Push the response handler

$http = new HttpClient(['handler' => $stack]);

$options = new Options();
$adapter = new GuzzleAdapter($http, $options);

$client = new Client($adapter);

Error/Exception management

Using the same approach you can convert InfluxDB errored responses in PHP Exception using the exception_handler. In that way when a query fail with an error message the handler convert that failure in a valid PHP Exception UnexceptionValueException

Just push the exception_handler layer in your GuzzleHTTP client

$stack->push(\InfluxDB\Handler\exception_handler()); // Push the response handler

Layer order

Handlers that modifies the InfluxDB response should be placed in order:

• exception_hanlder as first
• message_handler

You can append how many handlers you want

$stack->push(\InfluxDB\Handler\exception_handler());
$stack->push(\InfluxDB\Handler\message_handler());

In that way you will get new responses format and error messages