How to send Get and Post request with POCO Library and OAuth2 - poco-libraries

Question

I have a native window app program,and want access API of gitlab service,hope to get token using name and password with using POCO Library and OAuth2,but I don't know how to send Get and Post request to gitlab with OAuth2,and using POCO Library, please give me a example.
Here is the data that needs to be sent and received.
Requesting access token
POST request to /oauth/token with parameters:
{
"grant_type" : "password",
"username" : "user#example.com",
"password" : "secret"
}
Then, you'll receive the access token back in the response:
{
"access_token": "1f0af717251950dbd4d73154fdf0a474a5c5119adad999683f5b450c460726aa",
"token_type": "bearer",
"expires_in": 7200
}

Answer 1

First you need to create a HTTPRequest object like so:
Poco::Net::HTTPClientSession* session = Poco::Net::HTTPSessionFactory::defaultFactory().createClientSession(serverUri);
Poco::Net::HTTPRequest request(Poco::Net::HTTPRequest::HTTP_POST, serverUri.getPathAndQuery(), Poco::Net::HTTPMessage::HTTP_1_1);
Then create a HTMLForm:
Poco::Net::HTMLForm form;
form.add("grant_type", "password");
form.add("client_id", "client token");
form.add("client_secret", "client secret");
form.add("username", "user#example.com");
form.add("password", "secret");
form.prepareSubmit(request);
Send the request and write the form data into the output stream of the request:
std::ostream& requestStream = session->sendRequest(request);
form.write(requestStream);
Get the response out of the session:
Poco::Net::HTTPResponse response;
std::istream& responseStream = session->receiveResponse(response);
std::stringstream rawJson;
Poco::StreamCopier::copyStream(responseStream, rawJson);
Parse the raw JSON:
Poco::JSON::Parser parser;
Poco::JSON::Object::Ptr authObj = parser.parse(rawJson).extract<Poco::JSON::Object::Ptr>();
Create a new session for next request and attach an authorization header to the request:
Poco::Net::HTTPClientSession* dataSession = Poco::Net::HTTPSessionFactory::defaultFactory().createClientSession(dataUri);
Poco::Net::HTTPRequest dataRequest(Poco::Net::HTTPRequest::HTTP_GET, dataUri.getPathAndQuery(), Poco::Net::HTTPMessage::HTTP_1_1);
dataRequest.add("Authorization", "Bearer " + authObj->get("access_token"));
dataSession->sendRequest(dataRequest);
Get the response and read the data from stream:
std::stringstream data;
Poco::Net::HTTPResponse dataResponse;
Poco::StreamCopier::copyStream(dataSession->receiveResponse(dataResponse), data);
Hope it helps or points into the right direction.