Check user credentials against ews

[serious6]

Hi there, I was searching on methods which will allow me to check given user-credentials against the ews-api. But I currently did not find something nice. Perhabs it makes sense to have this implemented since I was wondering if many people would run into that?! I found some explanation on this here.

[barisaydinoglu]

A simple request to EmailMessage.bind() with dummy id like below may be used. This request responses with 401 Unauthorized when the credentials are wrong.

public boolean login(ExchangeService service) {
    try {
        EmailMessage.bind(service, new ItemId("__dummyId__"), PropertySet.IdOnly);
    } catch ( Exception e ) {
        if ( e.getMessage().contains("Unauthorized") ) {
            return false;
        }
    }
    return true;
}

[serious6]

thanks. I was aware that accessing a given resource would check credentials. In fact I was wondering if there would be a less noisy way to check this while not making expensive operations on the server. But just loading PropertySet.IdOnly seems reasonable.

[barisaydinoglu]

Here another possible solution. May require less effort on server.

public boolean login(ExchangeService service) {
    try {
        AlternateIdBase x = service.convertId(new AlternatePublicFolderId(IdFormat.EwsId, "__dummyId__"), IdFormat.EwsId);
    } catch ( Exception e ) {
        if ( e.getMessage().contains("Unauthorized") ) {
            return false;
        }
    }
    return true;
}

[serious6]

thanks. Perhabs if anybody could trace the communication and its effort this could be integrated as an official method with the ExchangeService and delegated to a feature-request. It may also be useful if the Service would throw a defined Exception AuthentificationException for example rather than a general one with given String. This may ref #157.

[barisaydinoglu]

i've tested 4 cases with junit. (using id="_")

because of the id is wrong, the requests have same effort on server, and throw "id is malformed". network elapsed time and response+request size of two methods are quite close. however, the communication size of EmailMessage.bind a little less than convertId.

so EmailMessage.bind can be selected.

	EmailMessage.bind(...)		service.convertId(...)
credentials	correct	wrong	correct	wrong
Request size:	545	545	557	557
Response size:	1066	0	1065	0
Total size:	1611	545	1622	557

[alexbelevantsev]

It doesn't work for non-English OS (more accurate, for non-English .Net Frameworks).