How to do http post using apache httpclient with web authentication?

I have searched a LOT for this and could not find a decent solution. The one using credentials provider is bad as it make double the amount of calls opposed to what is required i.e. it fires the request , gets a 401 and only then fires the request with the web auth credentials.

Anyone who has used android's http开发者_开发问答client library to do http post requests to a URL behind web auth successfully??

For HttpClient 4.0.x you use a HttpRequestInterceptor to enable preemptive authentication - since the AndroidHttpClient class doesn't expose the addRequestInterceptor(..) method you're probably going to have to use the DefaultHttpClient class.

This example will spam user1/user1 to any server interested. Adjust the AuthScope if you care even one bit about security.

DefaultHttpClient client = new DefaultHttpClient();
client.getCredentialsProvider().setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("user1", "user1"));
client.addRequestInterceptor(new HttpRequestInterceptor() {
    public void process(HttpRequest request, HttpContext context) throws HttpException, IOException {
        AuthState state = (AuthState) context.getAttribute(ClientContext.TARGET_AUTH_STATE);
        if (state.getAuthScheme() == null) {
            BasicScheme scheme = new BasicScheme();
            CredentialsProvider credentialsProvider = (CredentialsProvider) context.getAttribute(ClientContext.CREDS_PROVIDER);
            Credentials credentials = credentialsProvider.getCredentials(AuthScope.ANY);
            if (credentials == null) {
                throw new HttpException();
            }
            state.setAuthScope(AuthScope.ANY);
            state.setAuthScheme(scheme);
            state.setCredentials(credentials);
        }
    }
}, 0); // 0 = first, and you really want to be first.