ここにはたくさんの質問があります。GoogleCredential クラスを使用して、保存する必要のある既存の更新トークンから新しいアクセス トークンを取得します (MemoryCredentialStore など、任意の方法を使用します)。
アクセス トークンは 1 時間しか持続せず、これを変更する方法はありません。
インストールされたフローを使用した例を次に示します。
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Collections;
import java.util.List;
import java.util.Properties;
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.auth.oauth2.TokenResponse;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeRequestUrl;
import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.googleapis.auth.oauth2.GoogleTokenResponse;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson.JacksonFactory;
import com.google.api.services.bigquery.Bigquery;
import com.google.api.services.bigquery.Bigquery.Datasets;
import com.google.api.services.bigquery.BigqueryScopes;
import com.google.api.services.bigquery.model.DatasetList;
class BigQueryInstalledAuthDemo {
// Change this to your current project ID
private static final String PROJECT_NUMBER = "XXXXXXXXXX";
// Load Client ID/secret from client_secrets.json file.
private static final String CLIENTSECRETS_LOCATION = "client_secrets.json";
static GoogleClientSecrets clientSecrets = loadClientSecrets();
private static final String REDIRECT_URI = "urn:ietf:wg:oauth:2.0:oob";
// Objects for handling HTTP transport and JSON formatting of API calls
private static final HttpTransport HTTP_TRANSPORT = new NetHttpTransport();
private static final JsonFactory JSON_FACTORY = new JacksonFactory();
private static GoogleAuthorizationCodeFlow flow = null;
// BigQuery Client
static Bigquery bigquery;
public static void main(String[] args) throws IOException {
// Attempt to Load existing Refresh Token
String storedRefreshToken = loadRefreshToken();
// Check to see if the an existing refresh token was loaded.
// If so, create a credential and call refreshToken() to get a new
// access token.
if (storedRefreshToken != null) {
// Request a new Access token using the refresh token.
GoogleCredential credential = createCredentialWithRefreshToken(
HTTP_TRANSPORT, JSON_FACTORY, new TokenResponse().setRefreshToken(storedRefreshToken));
credential.refreshToken();
bigquery = buildService(credential);
// If there is no refresh token (or token.properties file), start the OAuth
// authorization flow.
} else {
String authorizeUrl = new GoogleAuthorizationCodeRequestUrl(
clientSecrets,
REDIRECT_URI,
Collections.singleton(BigqueryScopes.BIGQUERY)).setState("").build();
System.out.println("Paste this URL into a web browser to authorize BigQuery Access:\n" + authorizeUrl);
System.out.println("... and type the code you received here: ");
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String authorizationCode = in.readLine();
// Exchange the auth code for an access token and refesh token
Credential credential = exchangeCode(authorizationCode);
// Store the refresh token for future use.
storeRefreshToken(credential.getRefreshToken());
bigquery = buildService(credential);
}
// Make API calls using your client.
listDatasets(bigquery, PROJECT_NUMBER);
}
/**
* Builds an authorized BigQuery API client.
*/
private static Bigquery buildService(Credential credential) {
return new Bigquery.Builder(HTTP_TRANSPORT, JSON_FACTORY, credential).build();
}
/**
* Build an authorization flow and store it as a static class attribute.
*/
static GoogleAuthorizationCodeFlow getFlow() {
if (flow == null) {
flow = new GoogleAuthorizationCodeFlow.Builder(HTTP_TRANSPORT,
JSON_FACTORY,
clientSecrets,
Collections.singleton(BigqueryScopes.BIGQUERY))
.setAccessType("offline").setApprovalPrompt("force").build();
}
return flow;
}
/**
* Exchange the authorization code for OAuth 2.0 credentials.
*/
static Credential exchangeCode(String authorizationCode) throws IOException {
GoogleAuthorizationCodeFlow flow = getFlow();
GoogleTokenResponse response =
flow.newTokenRequest(authorizationCode).setRedirectUri(REDIRECT_URI).execute();
return flow.createAndStoreCredential(response, null);
}
/**
* No need to go through OAuth dance, get an access token using the
* existing refresh token.
*/
public static GoogleCredential createCredentialWithRefreshToken(HttpTransport transport,
JsonFactory jsonFactory, TokenResponse tokenResponse) {
return new GoogleCredential.Builder().setTransport(transport)
.setJsonFactory(jsonFactory)
.setClientSecrets(clientSecrets)
.build()
.setFromTokenResponse(tokenResponse);
}
/**
* Helper to load client ID/Secret from file.
*/
private static GoogleClientSecrets loadClientSecrets() {
try {
GoogleClientSecrets clientSecrets =
GoogleClientSecrets.load(new JacksonFactory(),
BigQueryInstalledAuthDemo.class.getResourceAsStream(CLIENTSECRETS_LOCATION));
return clientSecrets;
} catch (Exception e) {
System.out.println("Could not load clientsecrets.json");
e.printStackTrace();
}
return clientSecrets;
}
/**
* Helper to store a new refresh token in token.properties file.
*/
private static void storeRefreshToken(String refresh_token) {
Properties properties = new Properties();
properties.setProperty("refreshtoken", refresh_token);
System.out.println(properties.get("refreshtoken"));
try {
properties.store(new FileOutputStream("token.properties"), null);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Helper to load refresh token from the token.properties file.
*/
private static String loadRefreshToken(){
Properties properties = new Properties();
try {
properties.load(new FileInputStream("token.properties"));
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return (String) properties.get("refreshtoken");
}
/**
*
* List available Datasets.
*/
public static void listDatasets(Bigquery bigquery, String projectId)
throws IOException {
Datasets.List datasetRequest = bigquery.datasets().list(projectId);
DatasetList datasetList = datasetRequest.execute();
if (datasetList.getDatasets() != null) {
List<DatasetList.Datasets> datasets = datasetList.getDatasets();
System.out.println("Available datasets\n----------------");
for (com.google.api.services.bigquery.model.DatasetList.Datasets dataset : datasets) {
System.out.format("%s\n", dataset.getDatasetReference().getDatasetId());
}
}
}
}
更新トークンを保存して使用し、インストール済みのアプリケーションで新しいアクセス トークンを取得することによる承認の代わりに、サーバーからサーバーへのサービス アカウント承認フローを使用することもできます。この場合、アプリケーションは一意の秘密鍵を安全に保存して使用できる必要があります。Google Java API クライアントを使用したこのタイプのフローの例を次に示します。
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson.JacksonFactory;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.services.bigquery.Bigquery;
import com.google.api.services.bigquery.Bigquery.Datasets;
import com.google.api.services.bigquery.model.DatasetList;
import java.io.File;
import java.io.IOException;
import java.security.GeneralSecurityException;
public class JavaCommandLineServiceAccounts {
private static final String SCOPE = "https://www.googleapis.com/auth/bigquery";
private static final HttpTransport TRANSPORT = new NetHttpTransport();
private static final JsonFactory JSON_FACTORY = new JacksonFactory();
private static Bigquery bigquery;
public static void main(String[] args) throws IOException, GeneralSecurityException {
GoogleCredential credential = new GoogleCredential.Builder().setTransport(TRANSPORT)
.setJsonFactory(JSON_FACTORY)
.setServiceAccountId("XXXXXXX@developer.gserviceaccount.com")
.setServiceAccountScopes(SCOPE)
.setServiceAccountPrivateKeyFromP12File(new File("my_file.p12"))
.build();
bigquery = new Bigquery.Builder(TRANSPORT, JSON_FACTORY, credential)
.setApplicationName("BigQuery-Service-Accounts/0.1")
.setHttpRequestInitializer(credential).build();
Datasets.List datasetRequest = bigquery.datasets().list("publicdata");
DatasetList datasetList = datasetRequest.execute();
System.out.format("%s\n", datasetList.toPrettyString());
}
}