PHP Extension

Egyptian eReceipt OAuth2 Client Credentials

See more Egypt eReceipt Examples

Get an OAuth2 access token for the Egyptian eReceipt REST API using client credentials (no interactivity with a web browser required). PHP Extension

<?php

include("chilkat.php");

$success = false;

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

$http = new CkHttp();

// Note: Any provider of a REST API, such as the Egyptian government in this case, can make life 
// much easier for developers by providing one or more of the following in the API documentation:
// 
// 1) A sample CURL statement for each API call.
// 2) A Postman collection, or Swagger/OpenAPI specification file.
// 3) A sample of a raw HTTP request and response for each API call.
// 
// The sample CURL statements or raw HTTP request/responses do not need to comprehensively show all 
// possible options.  Providing a sample allows one to quickly make a successful API call.
// It also allows for code generation directly from the CURL, Postman collection, or raw request/response,
// and it tends to answer all questions about the format/structure of a request that, suprisingly,
// remain ambiguous or not obvious in other forms of documentation.

$req = new CkHttpRequest();
$req->AddParam('grant_type','client_credentials');
// Use your actual client ID and client secret...
$req->AddParam('client_id','d0394a9f-0607-40de-a978-2d3eb8375b04');
$req->AddParam('client_secret','6d62315e-d65a-4e41-9112-4195ea834edf');

$req->AddHeader('posserial','1234567899');
$req->AddHeader('pososversion','os');
$req->AddHeader('posmodelframework','1');
$req->AddHeader('presharedkey','03ac674216f3e1...');

// When writing this example, the documentation at https://sdk.invoicing.eta.gov.eg/ereceiptapi/01-authenticate-pos/
// shows us the HTTP verb and path (POST /connect/token), however,
// we don't see the actual domain where the request is to be sent.
// What are the endpoints???
// It took some searching, but we found some endpoints here:  https://sdk.invoicing.eta.gov.eg/faq/
// It's not immediately apparent which endpoint is to be used with a given API call.
// Why not just include the endpoint in the documentation for each REST API call?
// Endpoints are literally the #1 thing that needs to be known.
// They can't just be buried in a FAQ.  They should be up-front and obvious.
// 
// So.. we're guessing the endpoint is likely "https://invoicing.eta.gov.eg/connect/token"
$req->put_HttpVerb('POST');
$req->put_ContentType('application/x-www-form-urlencoded');

$resp = new CkHttpResponse();
$success = $http->HttpReq('https://invoicing.eta.gov.eg/connect/token',$req,$resp);
if ($success == false) {
    print $http->lastErrorText() . "\n";
    exit;
}

$sbResponseBody = new CkStringBuilder();
$resp->GetBodySb($sbResponseBody);

$jResp = new CkJsonObject();
$jResp->LoadSb($sbResponseBody);
$jResp->put_EmitCompact(false);

print 'Response Body:' . "\n";
print $jResp->emit() . "\n";

$respStatusCode = $resp->get_StatusCode();
print 'Response Status Code = ' . $respStatusCode . "\n";
if ($respStatusCode >= 400) {
    print 'Response Header:' . "\n";
    print $resp->header() . "\n";
    print 'Failed.' . "\n";
    exit;
}

// If successful, the OAuth2 access token JSON looks like this:

// {
//   "token_type": "Bearer",
//   "access_token": "eyJraW......R2sbqrY",
//   "expires_in": "3600",
//   "scope": "..."
// }

$token_type = $jResp->stringOf('token_type');
$access_token = $jResp->stringOf('access_token');
$expires_in = $jResp->stringOf('expires_in');
$scope = $jResp->stringOf('scope');

?>