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PHP Extension

ING Open Banking OAuth2 Client Credentials

See more OAuth2 Examples

Demonstrates how to get an access token for the ING Open Banking APIs using client credentials.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$cert = new CkCert();
$success = $cert->LoadFromFile('qa_data/certs_and_keys/ING/example_client_tls.cer');
if ($success == false) {
    print $cert->lastErrorText() . "\n";
    exit;
}

$bdPrivKey = new CkBinData();
$success = $bdPrivKey->LoadFile('qa_data/certs_and_keys/ING/example_client_tls.key');
if ($success == false) {
    print 'Failed to load example_client_tls.key' . "\n";
    exit;
}

// The OAuth 2.0 client_id for these certificates is e77d776b-90af-4684-bebc-521e5b2614dd. 
// Please note down this client_id since you will need it in the next steps to call the API.

$privKey = new CkPrivateKey();
$success = $privKey->LoadAnyFormat($bdPrivKey,'');
if ($success == false) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

// Associate the private key with the certificate.
$success = $cert->SetPrivateKey($privKey);
if ($success == false) {
    print $cert->lastErrorText() . "\n";
    exit;
}

$http = new CkHttp();

$success = $http->SetSslClientCert($cert);
if ($success == false) {
    print $http->lastErrorText() . "\n";
    exit;
}

// Calculate the Digest and add the "Digest" header.  Do the equivalent of this:
// payload="grant_type=client_credentials"
// payloadDigest=`echo -n "$payload" | openssl dgst -binary -sha256 | openssl base64`
// digest=SHA-256=$payloadDigest
$crypt = new CkCrypt2();
$crypt->put_HashAlgorithm('SHA256');
$crypt->put_EncodingMode('base64');
$payload = 'grant_type=client_credentials';
$payloadDigest = $crypt->hashStringENC($payload);

// Calculate the current date/time and add the Date header.  
// reqDate=$(LC_TIME=en_US.UTF-8 date -u "+%a, %d %b %Y %H:%M:%S GMT")  
$dt = new CkDateTime();
$dt->SetFromCurrentSystemTime();
// The desire date/time format is the "RFC822" format.
$http->SetRequestHeader('Date',$dt->getAsRfc822(false));

// Calculate signature for signing your request
// Duplicate the following code:

// 	httpMethod="post"
// 	reqPath="/oauth2/token"
// 	signingString="(request-target): $httpMethod $reqPath
// 	date: $reqDate
// 	digest: $digest"
// 	signature=`printf "$signingString" | openssl dgst -sha256 -sign "${certPath}example_client_signing.key" -passin "pass:changeit" | openssl base64 -A`

$httpMethod = 'POST';
$reqPath = '/oauth2/token';

$sbStringToSign = new CkStringBuilder();
$sbStringToSign->Append('(request-target): ');
$sbStringToSign->Append($httpMethod);
$sbStringToSign->ToLowercase();
$sbStringToSign->Append(' ');
$sbStringToSign->AppendLine($reqPath,false);

$sbStringToSign->Append('date: ');
$sbStringToSign->AppendLine($dt->getAsRfc822(false),false);

$sbStringToSign->Append('digest: SHA-256=');
$sbStringToSign->Append($payloadDigest);

$signingPrivKey = new CkPrivateKey();
$success = $signingPrivKey->LoadPemFile('qa_data/certs_and_keys/ING/example_client_signing.key');
if ($success == false) {
    print $signingPrivKey->lastErrorText() . "\n";
    exit;
}

$rsa = new CkRsa();
$success = $rsa->UsePrivateKey($signingPrivKey);
if ($success == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

$rsa->put_EncodingMode('base64');
$b64Signature = $rsa->signStringENC($sbStringToSign->getAsString(),'SHA256');

$sbAuthHdrVal = new CkStringBuilder();
$sbAuthHdrVal->Append('Signature keyId=\'e77d776b-90af-4684-bebc-521e5b2614dd\',');
$sbAuthHdrVal->Append('algorithm=\'rsa-sha256\',');
$sbAuthHdrVal->Append('headers=\'(request-target) date digest\',');
$sbAuthHdrVal->Append('signature=\'');
$sbAuthHdrVal->Append($b64Signature);
$sbAuthHdrVal->Append('\'');

$sbDigestHdrVal = new CkStringBuilder();
$sbDigestHdrVal->Append('SHA-256=');
$sbDigestHdrVal->Append($payloadDigest);

// Do the following CURL statement:

// 	curl -i -X POST "${httpHost}${reqPath}" \
// 	-H 'Accept: application/json' \
// 	-H 'Content-Type: application/x-www-form-urlencoded' \
// 	-H "Digest: ${digest}" \
// 	-H "Date: ${reqDate}" \
// 	-H "authorization: Signature keyId=\"$keyId\",algorithm=\"rsa-sha256\",headers=\"(request-target) date digest\",signature=\"$signature\"" \
// 	-d "${payload}" \
// 	--cert "${certPath}tlsCert.crt" \
// 	--key "${certPath}tlsCert.key"

$req = new CkHttpRequest();
$req->AddParam('grant_type','client_credentials');
$req->AddHeader('Accept','application/json');
$req->AddHeader('Date',$dt->getAsRfc822(false));
$req->AddHeader('Digest',$sbDigestHdrVal->getAsString());
$req->AddHeader('Authorization',$sbAuthHdrVal->getAsString());

$req->put_HttpVerb('POST');
$req->put_ContentType('application/x-www-form-urlencoded');

$resp = new CkHttpResponse();
$success = $http->HttpReq('https://api.sandbox.ing.com/oauth2/token',$req,$resp);
if ($success == false) {
    print $http->lastErrorText() . "\n";
    exit;
}

// If successful, the status code = 200
print 'Response Status Code: ' . $resp->get_StatusCode() . "\n";
print $resp->bodyStr() . "\n";

$json = new CkJsonObject();
$json->Load($resp->bodyStr());

$json->put_EmitCompact(false);
print $json->emit() . "\n";

// A successful response contains an access token such as:
// {
//   "access_token": "eyJhbGc ... bxI_SoPOBH9xmoM",
//   "expires_in": 905,
//   "scope": "payment-requests:view payment-requests:create payment-requests:close greetings:view virtual-ledger-accounts:fund-reservation:create virtual-ledger-accounts:fund-reservation:delete virtual-ledger-accounts:balance:view",
//   "token_type": "Bearer",
//   "keys": [
//     {
//       "kty": "RSA",
//       "n": "3l3rdz4...04VPkdV",
//       "e": "AQAB",
//       "use": "sig",
//       "alg": "RS256",
//       "x5t": "3c396700fc8cd709cf9cb5452a22bcde76985851"
//     }
//   ],
//   "client_id": "e77d776b-90af-4684-bebc-521e5b2614dd"
// }

// Use this online tool to generate parsing code from sample JSON: 
// Generate Parsing Code from JSON

$access_token = $json->stringOf('access_token');
$expires_in = $json->IntOf('expires_in');
$scope = $json->stringOf('scope');
$token_type = $json->stringOf('token_type');
$client_id = $json->stringOf('client_id');
$i = 0;
$count_i = $json->SizeOfArray('keys');
while ($i < $count_i) {
    $json->put_I($i);
    $kty = $json->stringOf('keys[i].kty');
    $n = $json->stringOf('keys[i].n');
    $e = $json->stringOf('keys[i].e');
    $use = $json->stringOf('keys[i].use');
    $alg = $json->stringOf('keys[i].alg');
    $x5t = $json->stringOf('keys[i].x5t');
    $i = $i + 1;
}

// This example will save the JSON containing the access key to a file so that
// a subsequent example can load it and then use the access key for a request, such as to create a payment request.
$json->WriteFile('qa_data/tokens/ing_access_token.json');

?>