#!/opt/bin/php -c/opt/php.ini

error_reporting(E_ALL | E_STRICT);

$AWS_LAMBDA_RUNTIME_API = getenv('AWS_LAMBDA_RUNTIME_API');

$http_codes = [100=>'Continue',101=>'Switching Protocols',102=>'Processing',200=>'OK',201=>'Created',202=>'Accepted',203=>'Non-Authoritative Information',204=>'No Content',205=>'Reset Content',206=>'Partial Content',207=>'Multi-Status',208=>'Already Reported',226=>'IM Used',300=>'Multiple Choices',301=>'Moved Permanently',302=>'Found',303=>'See Other',304=>'Not Modified',305=>'Use Proxy',306=>'Switch Proxy',307=>'Temporary Redirect',308=>'Permanent Redirect',400=>'Bad Request',401=>'Unauthorized',402=>'Payment Required',403=>'Forbidden',404=>'Not Found',405=>'Method Not Allowed',406=>'Not Acceptable',407=>'Proxy Authentication Required',408=>'Request Timeout',409=>'Conflict',410=>'Gone',411=>'Length Required',412=>'Precondition Failed',413=>'Request Entity Too Large',414=>'Request-URI Too Long',415=>'Unsupported Media Type',416=>'Requested Range Not Satisfiable',417=>'Expectation Failed',418=>'I\'m a teapot',419=>'Authentication Timeout',420=>'Enhance Your Calm',420=>'Method Failure',422=>'Unprocessable Entity',423=>'Locked',424=>'Failed Dependency',424=>'Method Failure',425=>'Unordered Collection',426=>'Upgrade Required',428=>'Precondition Required',429=>'Too Many Requests',431=>'Request Header Fields Too Large',444=>'No Response',449=>'Retry With',450=>'Blocked by Windows Parental Controls',451=>'Redirect',451=>'Unavailable For Legal Reasons',494=>'Request Header Too Large',495=>'Cert Error',496=>'No Cert',497=>'HTTP to HTTPS',499=>'Client Closed Request',500=>'Internal Server Error',501=>'Not Implemented',502=>'Bad Gateway',503=>'Service Unavailable',504=>'Gateway Timeout',505=>'HTTP Version Not Supported',506=>'Variant Also Negotiates',507=>'Insufficient Storage',508=>'Loop Detected',509=>'Bandwidth Limit Exceeded',510=>'Not Extended',511=>'Network Authentication Required',598=>'Network read timeout error',599=>'Network connect timeout error'];

function start_webserver() {

}

function fail($AWS_LAMBDA_RUNTIME_API, $invocation_id, $message) {

}

start_webserver();

while (true) {

$ch = curl_init("http://$AWS_LAMBDA_RUNTIME_API/2018-06-01/runtime/invocation/next");

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);

curl_setopt($ch, CURLOPT_FAILONERROR, TRUE);

$invocation_id = '';

curl_setopt($ch, CURLOPT_HEADERFUNCTION, function ($ch, $header) use (&$invocation_id) {

if (!preg_match('/:\s*/', $header)) {

return strlen($header);

}

[$name, $value] = preg_split('/:\s*/', $header, 2);

if (strtolower($name) == 'lambda-runtime-aws-request-id') {

$invocation_id = trim($value);

}

return strlen($header);

});

$body = '';

curl_setopt($ch, CURLOPT_WRITEFUNCTION, function ($ch, $chunk) use (&$body) {

$body .= $chunk;

return strlen($chunk);

});

curl_exec($ch);

if (curl_error($ch)) {

die('Failed to fetch next Lambda invocation: ' . curl_error($ch) . "\n");

}

if ($invocation_id == '') {

die("Failed to determine Lambda invocation ID\n");

}

curl_close($ch);

if (!$body) {

die("Empty Lambda invocation response\n");

}

$event = json_decode($body, TRUE);

if (!array_key_exists('requestContext', $event)) {

fail($AWS_LAMBDA_RUNTIME_API, $invocation_id, 'Event is not an API Gateway request');

continue;

}

$uri = $event['path'];

if (array_key_exists('multiValueQueryStringParameters', $event) && $event['multiValueQueryStringParameters']) {

$first = TRUE;

foreach ($event['multiValueQueryStringParameters'] as $name => $values) {

foreach ($values as $value) {

if ($first) {

$uri .= "?";

$first = FALSE;

} else {

$uri .= "&";

}

$uri .= $name;

if ($value != '') {

$uri .= '=' . $value;

}

}

}

}

$ch = curl_init("http://localhost:8000$uri");

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, FALSE);

if (array_key_exists('multiValueHeaders', $event)) {

$headers = array();

foreach ($event['multiValueHeaders'] as $name => $values) {

foreach ($values as $value) {

array_push($headers, "${name}: ${value}");

}

}

curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

}

curl_setopt($ch, CURLOPT_CUSTOMREQUEST, $event['httpMethod']);

if (array_key_exists('body', $event)) {

$body = $event['body'];

if (array_key_exists('isBase64Encoded', $event) && $event['isBase64Encoded']) {

$body = base64_decode($body);

}

} else {

$body = '';

}

if (strlen($body) > 0) {

curl_setopt($ch, CURLOPT_POSTFIELDS, $body);

}

$response = array();

$response['multiValueHeaders'] = array();

$response['body'] = '';

curl_setopt($ch, CURLOPT_HEADERFUNCTION, function ($ch, $header) use (&$response) {

if (preg_match('/HTTP\/1.1 (\d+) .*/', $header, $matches)) {

$response['statusCode'] = intval($matches[1]);

return strlen($header);

}

if (!preg_match('/:\s*/', $header)) {

return strlen($header);

}

[$name, $value] = preg_split('/:\s*/', $header, 2);

$name = trim($name);

$value = trim($value);

if ($name == '') {

return strlen($header);

}

if (!array_key_exists($name, $response['multiValueHeaders'])) {

$response['multiValueHeaders'][$name] = array();

}

array_push($response['multiValueHeaders'][$name], $value);

return strlen($header);

});

curl_setopt($ch, CURLOPT_WRITEFUNCTION, function ($ch, $chunk) use (&$response) {

$response['body'] .= $chunk;

return strlen($chunk);

});

curl_exec($ch);

curl_close($ch);

$ch = curl_init("http://$AWS_LAMBDA_RUNTIME_API/2018-06-01/runtime/invocation/$invocation_id/response");

$isALB = array_key_exists("elb", $event['requestContext']);

if ($isALB) { // Add Headers For ALB

$status = $response["statusCode"];

if (array_key_exists($status, $http_codes)) {

$response["statusDescription"] = "$status ". $http_codes[$status];

} else {

$response["statusDescription"] = "$status Unknown";

}

$response["isBase64Encoded"] = false;

}

$response_json = json_encode($response);

curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');

curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

curl_setopt($ch, CURLOPT_POSTFIELDS, $response_json);

if (!$isALB){

curl_setopt($ch, CURLOPT_HTTPHEADER, array(

'Content-Type: application/json',

'Content-Length: ' . strlen($response_json)

));

}

curl_exec($ch);

curl_close($ch);

}