Google Cloud Print User credentials required

问题

I am implement google cloud print service for my (java) web application,I have followed all the instruction but still getting "Credentials required" in response.Here is my code :

public static void main(String[] args) {
    HttpPost printPost = new HttpPost(
            "https://www.google.com/cloudprint/search?output=json");
    printPost.setHeader("Authorization",
            "GoogleLogin auth=" +getAccessToken());
    printPost.setHeader("scope",
            "https://www.googleapis.com/auth/cloudprint");
    printPost.setHeader("X-CloudPrint-Proxy", "printingTest");
    DefaultHttpClient httpclient = new DefaultHttpClient();
    try {
        HttpResponse printResponse = httpclient.execute(printPost);
        System.out.println(printResponse.getStatusLine());
    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}
public static String getAccessToken() {

    Credential credential = new GoogleCredential.Builder()
            .setTransport(new NetHttpTransport())
            .setJsonFactory(new JacksonFactory())
            .setClientSecrets(
                    "client_id",
                    "client_secret").build();
    try {
        credential
                .setRefreshToken("refresh_token");
        credential.refreshToken();
        return credential.getAccessToken();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return null;

}

This is a simple search hit.

回答1:

use "Bearer " instead of "GoogleLogin auth=" in header while setting Authorization access token, also note the space with bearer it is important

来源：https://stackoverflow.com/questions/45279644/google-cloud-print-user-credentials-required