Perl

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). Perl

use chilkat();

$success = 0;

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

$http = chilkat::CkHttp->new();

# 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 = chilkat::CkHttpRequest->new();
$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 = chilkat::CkHttpResponse->new();
$success = $http->HttpReq("https://invoicing.eta.gov.eg/connect/token",$req,$resp);
if ($success == 0) {
    print $http->lastErrorText() . "\r\n";
    exit;
}

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

$jResp = chilkat::CkJsonObject->new();
$jResp->LoadSb($sbResponseBody);
$jResp->put_EmitCompact(0);

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

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