通过API从Athena Query返回JSON

Question

I am able to use the Athena API with startQueryExecution() to create a CSV file of the responses in S3. However, I would like to be able to return to my application a JSON response so I can further process the data. I am trying to return JSON results after I run startQueryExecution() via the API, how do I can get the results as a JSON response back?

I am using the AWS PHP SDK [ https://aws.amazon.com/sdk-for-php/] , however this is relevant to any language since I can not find any answers to actually getting a response back, it just saves a CSV file to S3.

$athena = AWS::createClient('athena');
$queryx = 'SELECT * FROM elb_logs LIMIT 20';

$result = $athena->startQueryExecution([
    'QueryExecutionContext' => [
        'Database' => 'sampledb',
    ],
    'QueryString' => 'SELECT request_ip FROM elb_logs LIMIT 20', // REQUIRED
    'ResultConfiguration' => [ // REQUIRED
        'EncryptionConfiguration' => [
            'EncryptionOption' => 'SSE_S3' // REQUIRED
        ],
        'OutputLocation' => 's3://xxxxxx/', // REQUIRED
    ],
]);

// check completion : getQueryExecution()
$exId = $result['QueryExecutionId'];

sleep(6);

$checkExecution = $athena->getQueryExecution([
    'QueryExecutionId' => $exId, // REQUIRED
]);


if($checkExecution["QueryExecution"]["Status"]["State"] == 'SUCCEEDED')
{
    $dataOutput = $athena->getQueryResults([
        'QueryExecutionId' => $result['QueryExecutionId'], // REQUIRED
    ]);

      while (($data = fgetcsv($dataOutput, 1000, ",")) !== FALSE) {
        $num = count($data);
        echo "<p> $num fields in line $row: <br /></p>\n";
        $row++;
        for ($c=0; $c < $num; $c++) {
            echo $data[$c] . "<br />\n";
        }
      }         

}

Answer 1

The Amazon Athena SDK will return the results of a query and then you can write (send) this as JSON. The SDK will not do this for you itself.

The API startQueryExecution() retuns QueryExecutionId. Use this to call getQueryExecution() to determine if the query is complete. Once the query completes call getQueryResults().

You can then process each row in the result set.