com.box.sdk.BoxAPIConnection Maven / Gradle / Ivy
package com.box.sdk;
import java.net.MalformedURLException;
import java.net.Proxy;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import com.eclipsesource.json.JsonObject;
/**
* Represents an authenticated connection to the Box API.
*
* This class handles storing authentication information, automatic token refresh, and rate-limiting. It can also be
* used to configure the Box API endpoint URL in order to hit a different version of the API. Multiple instances of
* BoxAPIConnection may be created to support multi-user login.
*/
public class BoxAPIConnection {
/**
* The default maximum number of times an API request will be tried when an error occurs.
*/
public static final int DEFAULT_MAX_ATTEMPTS = 3;
private static final String TOKEN_URL_STRING = "https://api.box.com/oauth2/token";
private static final String DEFAULT_BASE_URL = "https://api.box.com/2.0/";
private static final String DEFAULT_BASE_UPLOAD_URL = "https://upload.box.com/api/2.0/";
/**
* The amount of buffer time, in milliseconds, to use when determining if an access token should be refreshed. For
* example, if REFRESH_EPSILON = 60000 and the access token expires in less than one minute, it will be refreshed.
*/
private static final long REFRESH_EPSILON = 60000;
private final String clientID;
private final String clientSecret;
private final ReadWriteLock refreshLock;
// These volatile fields are used when determining if the access token needs to be refreshed. Since they are used in
// the double-checked lock in getAccessToken(), they must be atomic.
private volatile long lastRefresh;
private volatile long expires;
private Proxy proxy;
private String proxyUsername;
private String proxyPassword;
private String userAgent;
private String accessToken;
private String refreshToken;
private String tokenURL;
private String baseURL;
private String baseUploadURL;
private boolean autoRefresh;
private int maxRequestAttempts;
private List listeners;
private RequestInterceptor interceptor;
/**
* Constructs a new BoxAPIConnection that authenticates with a developer or access token.
* @param accessToken a developer or access token to use for authenticating with the API.
*/
public BoxAPIConnection(String accessToken) {
this(null, null, accessToken, null);
}
/**
* Constructs a new BoxAPIConnection with an access token that can be refreshed.
* @param clientID the client ID to use when refreshing the access token.
* @param clientSecret the client secret to use when refreshing the access token.
* @param accessToken an initial access token to use for authenticating with the API.
* @param refreshToken an initial refresh token to use when refreshing the access token.
*/
public BoxAPIConnection(String clientID, String clientSecret, String accessToken, String refreshToken) {
this.clientID = clientID;
this.clientSecret = clientSecret;
this.accessToken = accessToken;
this.refreshToken = refreshToken;
this.tokenURL = TOKEN_URL_STRING;
this.baseURL = DEFAULT_BASE_URL;
this.baseUploadURL = DEFAULT_BASE_UPLOAD_URL;
this.autoRefresh = true;
this.maxRequestAttempts = DEFAULT_MAX_ATTEMPTS;
this.refreshLock = new ReentrantReadWriteLock();
this.userAgent = "Box Java SDK v2.1.1";
this.listeners = new ArrayList();
}
/**
* Constructs a new BoxAPIConnection with an auth code that was obtained from the first half of OAuth.
* @param clientID the client ID to use when exchanging the auth code for an access token.
* @param clientSecret the client secret to use when exchanging the auth code for an access token.
* @param authCode an auth code obtained from the first half of the OAuth process.
*/
public BoxAPIConnection(String clientID, String clientSecret, String authCode) {
this(clientID, clientSecret, null, null);
this.authenticate(authCode);
}
/**
* Constructs a new BoxAPIConnection.
* @param clientID the client ID to use when exchanging the auth code for an access token.
* @param clientSecret the client secret to use when exchanging the auth code for an access token.
*/
public BoxAPIConnection(String clientID, String clientSecret) {
this(clientID, clientSecret, null, null);
}
/**
* Restores a BoxAPIConnection from a saved state.
*
* @see #save
* @param clientID the client ID to use with the connection.
* @param clientSecret the client secret to use with the connection.
* @param state the saved state that was created with {@link #save}.
* @return a restored API connection.
*/
public static BoxAPIConnection restore(String clientID, String clientSecret, String state) {
BoxAPIConnection api = new BoxAPIConnection(clientID, clientSecret);
api.restore(state);
return api;
}
/**
* Authenticates the API connection by obtaining access and refresh tokens using the auth code that was obtained
* from the first half of OAuth.
* @param authCode the auth code obtained from the first half of the OAuth process.
*/
public void authenticate(String authCode) {
URL url = null;
try {
url = new URL(this.tokenURL);
} catch (MalformedURLException e) {
assert false : "An invalid token URL indicates a bug in the SDK.";
throw new RuntimeException("An invalid token URL indicates a bug in the SDK.", e);
}
String urlParameters = String.format("grant_type=authorization_code&code=%s&client_id=%s&client_secret=%s",
authCode, this.clientID, this.clientSecret);
BoxAPIRequest request = new BoxAPIRequest(this, url, "POST");
request.shouldAuthenticate(false);
request.setBody(urlParameters);
BoxJSONResponse response = (BoxJSONResponse) request.send();
String json = response.getJSON();
JsonObject jsonObject = JsonObject.readFrom(json);
this.accessToken = jsonObject.get("access_token").asString();
this.refreshToken = jsonObject.get("refresh_token").asString();
this.lastRefresh = System.currentTimeMillis();
this.expires = jsonObject.get("expires_in").asLong() * 1000;
}
/**
* Gets the client ID.
* @return the client ID.
*/
public String getClientID() {
return this.clientID;
}
/**
* Gets the client secret.
* @return the client secret.
*/
public String getClientSecret() {
return this.clientSecret;
}
/**
* Sets the amount of time for which this connection's access token is valid before it must be refreshed.
* @param milliseconds the number of milliseconds for which the access token is valid.
*/
public void setExpires(long milliseconds) {
this.expires = milliseconds;
}
/**
* Gets the amount of time for which this connection's access token is valid.
* @return the amount of time in milliseconds.
*/
public long getExpires() {
return this.expires;
}
/**
* Gets the token URL that's used to request access tokens. The default value is
* "https://www.box.com/api/oauth2/token".
* @return the token URL.
*/
public String getTokenURL() {
return this.tokenURL;
}
/**
* Sets the token URL that's used to request access tokens. For example, the default token URL is
* "https://www.box.com/api/oauth2/token".
* @param tokenURL the token URL.
*/
public void setTokenURL(String tokenURL) {
this.tokenURL = tokenURL;
}
/**
* Gets the base URL that's used when sending requests to the Box API. The default value is
* "https://api.box.com/2.0/".
* @return the base URL.
*/
public String getBaseURL() {
return this.baseURL;
}
/**
* Sets the base URL to be used when sending requests to the Box API. For example, the default base URL is
* "https://api.box.com/2.0/".
* @param baseURL a base URL
*/
public void setBaseURL(String baseURL) {
this.baseURL = baseURL;
}
/**
* Gets the base upload URL that's used when performing file uploads to Box.
* @return the base upload URL.
*/
public String getBaseUploadURL() {
return this.baseUploadURL;
}
/**
* Sets the base upload URL to be used when performing file uploads to Box.
* @param baseUploadURL a base upload URL.
*/
public void setBaseUploadURL(String baseUploadURL) {
this.baseUploadURL = baseUploadURL;
}
/**
* Gets the user agent that's used when sending requests to the Box API.
* @return the user agent.
*/
public String getUserAgent() {
return this.userAgent;
}
/**
* Sets the user agent to be used when sending requests to the Box API.
* @param userAgent the user agent.
*/
public void setUserAgent(String userAgent) {
this.userAgent = userAgent;
}
/**
* Gets an access token that can be used to authenticate an API request. This method will automatically refresh the
* access token if it has expired since the last call to getAccessToken().
* @return a valid access token that can be used to authenticate an API request.
*/
public String getAccessToken() {
if (this.autoRefresh && this.canRefresh() && this.needsRefresh()) {
this.refreshLock.writeLock().lock();
try {
if (this.needsRefresh()) {
this.refresh();
}
} finally {
this.refreshLock.writeLock().unlock();
}
}
return this.accessToken;
}
/**
* Sets the access token to use when authenticating API requests.
* @param accessToken a valid access token to use when authenticating API requests.
*/
public void setAccessToken(String accessToken) {
this.accessToken = accessToken;
}
/**
* Gets the refresh lock to be used when refreshing an access token.
* @return the refresh lock.
*/
protected ReadWriteLock getRefreshLock() {
return this.refreshLock;
}
/**
* Gets a refresh token that can be used to refresh an access token.
* @return a valid refresh token.
*/
public String getRefreshToken() {
return this.refreshToken;
}
/**
* Sets the refresh token to use when refreshing an access token.
* @param refreshToken a valid refresh token.
*/
public void setRefreshToken(String refreshToken) {
this.refreshToken = refreshToken;
}
/**
* Gets the last time that the access token was refreshed.
*
* @return the last refresh time in milliseconds.
*/
public long getLastRefresh() {
return this.lastRefresh;
}
/**
* Sets the last time that the access token was refreshed.
*
* This value is used when determining if an access token needs to be auto-refreshed. If the amount of time since
* the last refresh exceeds the access token's expiration time, then the access token will be refreshed.
*
* @param lastRefresh the new last refresh time in milliseconds.
*/
public void setLastRefresh(long lastRefresh) {
this.lastRefresh = lastRefresh;
}
/**
* Enables or disables automatic refreshing of this connection's access token. Defaults to true.
* @param autoRefresh true to enable auto token refresh; otherwise false.
*/
public void setAutoRefresh(boolean autoRefresh) {
this.autoRefresh = autoRefresh;
}
/**
* Gets whether or not automatic refreshing of this connection's access token is enabled. Defaults to true.
* @return true if auto token refresh is enabled; otherwise false.
*/
public boolean getAutoRefresh() {
return this.autoRefresh;
}
/**
* Gets the maximum number of times an API request will be tried when an error occurs.
* @return the maximum number of request attempts.
*/
public int getMaxRequestAttempts() {
return this.maxRequestAttempts;
}
/**
* Sets the maximum number of times an API request will be tried when an error occurs.
* @param attempts the maximum number of request attempts.
*/
public void setMaxRequestAttempts(int attempts) {
this.maxRequestAttempts = attempts;
}
/**
* Gets the proxy value to use for API calls to Box.
* @return the current proxy.
*/
public Proxy getProxy() {
return this.proxy;
}
/**
* Sets the proxy to use for API calls to Box.
* @param proxy the proxy to use for API calls to Box.
*/
public void setProxy(Proxy proxy) {
this.proxy = proxy;
}
/**
* Gets the username to use for a proxy that requires basic auth.
* @return the username to use for a proxy that requires basic auth.
*/
public String getProxyUsername() {
return this.proxyUsername;
}
/**
* Sets the username to use for a proxy that requires basic auth.
* @param proxyUsername the username to use for a proxy that requires basic auth.
*/
public void setProxyUsername(String proxyUsername) {
this.proxyUsername = proxyUsername;
}
/**
* Gets the password to use for a proxy that requires basic auth.
* @return the password to use for a proxy that requires basic auth.
*/
public String getProxyPassword() {
return this.proxyPassword;
}
/**
* Sets the password to use for a proxy that requires basic auth.
* @param proxyPassword the password to use for a proxy that requires basic auth.
*/
public void setProxyPassword(String proxyPassword) {
this.proxyPassword = proxyPassword;
}
/**
* Determines if this connection's access token can be refreshed. An access token cannot be refreshed if a refresh
* token was never set.
* @return true if the access token can be refreshed; otherwise false.
*/
public boolean canRefresh() {
return this.refreshToken != null;
}
/**
* Determines if this connection's access token has expired and needs to be refreshed.
* @return true if the access token needs to be refreshed; otherwise false.
*/
public boolean needsRefresh() {
boolean needsRefresh;
this.refreshLock.readLock().lock();
long now = System.currentTimeMillis();
long tokenDuration = (now - this.lastRefresh);
needsRefresh = (tokenDuration >= this.expires - REFRESH_EPSILON);
this.refreshLock.readLock().unlock();
return needsRefresh;
}
/**
* Refresh's this connection's access token using its refresh token.
* @throws IllegalStateException if this connection's access token cannot be refreshed.
*/
public void refresh() {
this.refreshLock.writeLock().lock();
if (!this.canRefresh()) {
this.refreshLock.writeLock().unlock();
throw new IllegalStateException("The BoxAPIConnection cannot be refreshed because it doesn't have a "
+ "refresh token.");
}
URL url = null;
try {
url = new URL(this.tokenURL);
} catch (MalformedURLException e) {
this.refreshLock.writeLock().unlock();
assert false : "An invalid refresh URL indicates a bug in the SDK.";
throw new RuntimeException("An invalid refresh URL indicates a bug in the SDK.", e);
}
String urlParameters = String.format("grant_type=refresh_token&refresh_token=%s&client_id=%s&client_secret=%s",
this.refreshToken, this.clientID, this.clientSecret);
BoxAPIRequest request = new BoxAPIRequest(this, url, "POST");
request.shouldAuthenticate(false);
request.setBody(urlParameters);
String json;
try {
BoxJSONResponse response = (BoxJSONResponse) request.send();
json = response.getJSON();
} catch (BoxAPIException e) {
this.notifyError(e);
this.refreshLock.writeLock().unlock();
throw e;
}
JsonObject jsonObject = JsonObject.readFrom(json);
this.accessToken = jsonObject.get("access_token").asString();
this.refreshToken = jsonObject.get("refresh_token").asString();
this.lastRefresh = System.currentTimeMillis();
this.expires = jsonObject.get("expires_in").asLong() * 1000;
this.notifyRefresh();
this.refreshLock.writeLock().unlock();
}
/**
* Restores a saved connection state into this BoxAPIConnection.
*
* @see #save
* @param state the saved state that was created with {@link #save}.
*/
public void restore(String state) {
JsonObject json = JsonObject.readFrom(state);
String accessToken = json.get("accessToken").asString();
String refreshToken = json.get("refreshToken").asString();
long lastRefresh = json.get("lastRefresh").asLong();
long expires = json.get("expires").asLong();
String userAgent = json.get("userAgent").asString();
String tokenURL = json.get("tokenURL").asString();
String baseURL = json.get("baseURL").asString();
String baseUploadURL = json.get("baseUploadURL").asString();
boolean autoRefresh = json.get("autoRefresh").asBoolean();
int maxRequestAttempts = json.get("maxRequestAttempts").asInt();
this.accessToken = accessToken;
this.refreshToken = refreshToken;
this.lastRefresh = lastRefresh;
this.expires = expires;
this.userAgent = userAgent;
this.tokenURL = tokenURL;
this.baseURL = baseURL;
this.baseUploadURL = baseUploadURL;
this.autoRefresh = autoRefresh;
this.maxRequestAttempts = maxRequestAttempts;
}
/**
* Notifies a refresh event to all the listeners.
*/
protected void notifyRefresh() {
for (BoxAPIConnectionListener listener : this.listeners) {
listener.onRefresh(this);
}
}
/**
* Notifies an error event to all the listeners.
* @param error A BoxAPIException instance.
*/
protected void notifyError(BoxAPIException error) {
for (BoxAPIConnectionListener listener : this.listeners) {
listener.onError(this, error);
}
}
/**
* Add a listener to listen to Box API connection events.
* @param listener a listener to listen to Box API connection.
*/
public void addListener(BoxAPIConnectionListener listener) {
this.listeners.add(listener);
}
/**
* Remove a listener listening to Box API connection events.
* @param listener the listener to remove.
*/
public void removeListener(BoxAPIConnectionListener listener) {
this.listeners.remove(listener);
}
/**
* Gets the RequestInterceptor associated with this API connection.
* @return the RequestInterceptor associated with this API connection.
*/
public RequestInterceptor getRequestInterceptor() {
return this.interceptor;
}
/**
* Sets a RequestInterceptor that can intercept requests and manipulate them before they're sent to the Box API.
* @param interceptor the RequestInterceptor.
*/
public void setRequestInterceptor(RequestInterceptor interceptor) {
this.interceptor = interceptor;
}
/**
* Saves the state of this connection to a string so that it can be persisted and restored at a later time.
*
* Note that proxy settings aren't automatically saved or restored. This is mainly due to security concerns
* around persisting proxy authentication details to the state string. If your connection uses a proxy, you will
* have to manually configure it again after restoring the connection.
*
* @see #restore
* @return the state of this connection.
*/
public String save() {
JsonObject state = new JsonObject()
.add("accessToken", this.accessToken)
.add("refreshToken", this.refreshToken)
.add("lastRefresh", this.lastRefresh)
.add("expires", this.expires)
.add("userAgent", this.userAgent)
.add("tokenURL", this.tokenURL)
.add("baseURL", this.baseURL)
.add("baseUploadURL", this.baseUploadURL)
.add("autoRefresh", this.autoRefresh)
.add("maxRequestAttempts", this.maxRequestAttempts);
return state.toString();
}
String lockAccessToken() {
if (this.autoRefresh && this.canRefresh() && this.needsRefresh()) {
this.refreshLock.writeLock().lock();
try {
if (this.needsRefresh()) {
this.refresh();
}
this.refreshLock.readLock().lock();
} finally {
this.refreshLock.writeLock().unlock();
}
} else {
this.refreshLock.readLock().lock();
}
return this.accessToken;
}
void unlockAccessToken() {
this.refreshLock.readLock().unlock();
}
}