package com.almende.eve.agent.google;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.Logger;
import org.joda.time.DateTime;
import com.almende.eve.agent.Agent;
import com.almende.eve.agent.TaskAgent;
import com.almende.eve.agent.annotation.Name;
import com.almende.eve.agent.annotation.Required;
import com.almende.eve.config.Config;
import com.almende.eve.entity.calendar.Authorization;
import com.almende.eve.rpc.jsonrpc.JSONRPCException;
import com.almende.eve.rpc.jsonrpc.JSONRPCException.CODE;
import com.almende.eve.rpc.jsonrpc.jackson.JOM;
import com.almende.eve.state.State;
import com.almende.util.HttpUtil;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
public class GoogleTaskAgent extends Agent implements TaskAgent {
private Logger logger = Logger.getLogger(this.getClass().getName());
private String OAUTH_URI = "https://accounts.google.com/o/oauth2";
private String CALENDAR_URI = "https://www.googleapis.com/tasks/v1/";
/**
* Set access token and refresh token, used to authorize the calendar agent.
* These tokens must be retrieved via Oauth 2.0 authorization.
* @param access_token
* @param token_type
* @param expires_in
* @param refresh_token
* @throws IOException
*/
public void setAuthorization (
@Name("access_token") String access_token,
@Name("token_type") String token_type,
@Name("expires_in") Integer expires_in,
@Name("refresh_token") String refresh_token) throws IOException {
logger.info("setAuthorization");
State state = getState();
// retrieve user information
String url = "https://www.googleapis.com/oauth2/v1/userinfo";
Map<String, String> headers = new HashMap<String, String>();
headers.put("Authorization", token_type + " " + access_token);
String resp = HttpUtil.get(url, headers);
ObjectNode info = JOM.getInstance().readValue(resp, ObjectNode.class);
String email = info.has("email") ? info.get("email").asText() : null;
String name = info.has("name") ? info.get("name").asText() : null;
DateTime expires_at = calculateExpiresAt(expires_in);
Authorization auth = new Authorization(access_token, token_type,
expires_at, refresh_token);
// store the tokens in the state
state.put("auth", auth);
state.put("email", email);
state.put("name", name);
}
/**
* Calculate the expiration time from a life time
* @param expires_in Expiration time in seconds
* @return
*/
private DateTime calculateExpiresAt(Integer expires_in) {
DateTime expires_at = null;
if (expires_in != null && expires_in != 0) {
// calculate expiration time, and subtract 5 minutes for safety
expires_at = DateTime.now().plusSeconds(expires_in).minusMinutes(5);
}
return expires_at;
}
/**
* Refresh the access token using the refresh token
* the tokens in provided authorization object will be updated
* @param auth
* @throws Exception
*/
private void refreshAuthorization (Authorization auth) throws Exception {
String refresh_token = (auth != null) ? auth.getRefreshToken() : null;
if (refresh_token == null) {
throw new Exception("No refresh token available");
}
Config config = getAgentFactory().getConfig();
String client_id = config.get("google", "client_id");
String client_secret = config.get("google", "client_secret");
// retrieve new access_token using the refresh_token
Map<String, String> params = new HashMap<String, String>();
params.put("client_id", client_id);
params.put("client_secret", client_secret);
params.put("refresh_token", refresh_token);
params.put("grant_type", "refresh_token");
String resp = HttpUtil.postForm(OAUTH_URI + "/token", params);
ObjectNode json = JOM.getInstance().readValue(resp, ObjectNode.class);
if (!json.has("access_token")) {
// TODO: give more specific error message
throw new Exception("Retrieving new access token failed");
}
// update authorization
if (json.has("access_token")) {
auth.setAccessToken(json.get("access_token").asText());
}
if (json.has("expires_in")) {
Integer expires_in = json.get("expires_in").asInt();
DateTime expires_at = calculateExpiresAt(expires_in);
auth.setExpiresAt(expires_at);
}
}
/**
* Get ready-made HTTP request headers containing the authorization token
* Example usage: HttpUtil.get(url, getAuthorizationHeaders());
* @return
* @throws Exception
*/
private Map<String, String> getAuthorizationHeaders () throws Exception {
Authorization auth = getAuthorization();
String access_token = (auth != null) ? auth.getAccessToken() : null;
if (access_token == null) {
throw new Exception("No authorization token available");
}
String token_type = (auth != null) ? auth.getTokenType() : null;
if (token_type == null) {
throw new Exception("No token type available");
}
Map<String, String> headers = new HashMap<String, String>();
headers.put("Authorization", token_type + " " + access_token);
return headers;
}
/**
* Retrieve authorization tokens
* @return
* @throws Exception
*/
private Authorization getAuthorization() throws Exception {
Authorization auth = (Authorization) getState().get("auth");
// check if access_token is expired
DateTime expires_at = (auth != null) ? auth.getExpiresAt() : null;
if (expires_at != null && expires_at.isBeforeNow()) {
// TODO: remove this logging
logger.info("access token is expired. refreshing now...");
refreshAuthorization(auth);
getState().put("auth", auth);
}
return auth;
}
/**
* Get the calendar agents version
*/
@Override
public String getDescription() {
return "This agent gives access to a Google Tasks. " +
"It allows to search tasks " +
"and add, edit, or remove tasks.";
}
/**
* Get the calendar agents description
*/
@Override
public String getVersion() {
return "0.1";
}
/**
* Get the username associated with the tasks
* @return name
*/
@Override
public String getUsername() {
return (String) getState().get("name");
}
/**
* Get the email associated with the tasks
* @return name
*/
@Override
public String getEmail() {
return (String) getState().get("email");
}
/**
* Retrieve a list with all calendars in this google calendar
* @return String with id of the task list
*/
private String getDefaultTaskList() throws Exception {
String defaultList=(String) getState().get("defaultList");
if(defaultList==null) {
ArrayNode taskLists = getTaskList();
for(JsonNode taskList : taskLists) {
if(taskList.get("title").textValue().equals("Paige Task List")){
getState().put("defaultList", taskList.get("id").textValue());
return taskList.get("id").textValue();
}
}
}
// No default list found so going to create one
if(defaultList==null) {
ObjectNode taskList = JOM.createObjectNode();
taskList.put("title", "Paige Task List");
taskList = createTaskList(taskList);
defaultList = taskList.get("id").textValue();
getState().put("defaultList", defaultList);
}
return defaultList;
}
/**
* Create a task list
* @param taskList JSON structure containing a taskList
* @return JSON sturcture with created tasklist
*/
public ObjectNode createTaskList(@Name("taskList") ObjectNode taskList)
throws Exception {
String url = CALENDAR_URI + "users/@me/lists";
// perform POST request
ObjectMapper mapper = JOM.getInstance();
String body = mapper.writeValueAsString(taskList);
Map<String, String> headers = getAuthorizationHeaders();
headers.put("Content-Type", "application/json");
String resp = HttpUtil.post(url, body, headers);
ObjectNode createdTaskList = mapper.readValue(resp, ObjectNode.class);
// check for errors
if (createdTaskList.has("error")) {
ObjectNode error = (ObjectNode)createdTaskList.get("error");
throw new JSONRPCException(error);
}
logger.info("createTaskList=" + JOM.getInstance().writeValueAsString(createdTaskList));
return createdTaskList;
}
/**
* Retrieve a list with all task lists in this google tasks
*/
@Override
public ArrayNode getTaskList() throws Exception {
String url = CALENDAR_URI + "users/@me/lists";
String resp = HttpUtil.get(url, getAuthorizationHeaders());
ObjectNode calendars = JOM.getInstance().readValue(resp, ObjectNode.class);
// check for errors
if (calendars.has("error")) {
ObjectNode error = (ObjectNode)calendars.get("error");
throw new JSONRPCException(error);
}
// get items from response
ArrayNode items = null;
if (calendars.has("items")) {
items = (ArrayNode)calendars.get("items");
}
else {
items = JOM.createArrayNode();
}
return items;
}
/**
* Retrieve a list of task on a certain task list
* @param dueMin Minimal due time (optional)
* @param dueMax Maximal due time (optional)
* @param calendarId Optional task listid. the default task list is
* used by default
*/
@Override
public ArrayNode getTasks(@Required(false) @Name("dueMin") String dueMin,
@Required(false) @Name("dueMax") String dueMax,
@Required(false) @Name("taskListId") String taskListId)
throws Exception {
if (taskListId == null) {
taskListId = getDefaultTaskList();
}
if (taskListId == null) {
throw new Exception("No tasklist given and no default list found");
}
// built url with query parameters
String url = CALENDAR_URI + "lists/" + taskListId + "/tasks";
Map<String, String> params = new HashMap<String, String>();
if (dueMin != null) {
params.put("dueMin", new DateTime(dueMin).toString());
}
if (dueMax != null) {
params.put("dueMax", new DateTime(dueMax).toString());
}
// Set singleEvents=true to expand recurring events into instances
//params.put("singleEvents", "true");
url = HttpUtil.appendQueryParams(url, params);
// perform GET request
Map<String, String> headers = getAuthorizationHeaders();
String resp = HttpUtil.get(url, headers);
ObjectMapper mapper = JOM.getInstance();
ObjectNode json = mapper.readValue(resp, ObjectNode.class);
// check for errors
if (json.has("error")) {
ObjectNode error = (ObjectNode)json.get("error");
throw new JSONRPCException(error);
}
// get items from the response
ArrayNode items = null;
if (json.has("items")){
items = (ArrayNode) json.get("items");
/* TODO: cleanup?
// convert from Google to Eve event
for (int i = 0; i < items.size(); i++) {
ObjectNode item = (ObjectNode) items.get(i);
toEveEvent(item);
}
*/
}
else {
items = JOM.createArrayNode();
}
return items;
}
/**
* Get a single task by id
* @param taskId Id of the task
* @param taksListId Optional task listid. the default task list is
* used by default
*/
@Override
public ObjectNode getTask(@Name("taskId") String taskId,
@Required(false) @Name("taskListId") String taskListId)
throws Exception {
if (taskListId == null) {
taskListId = getDefaultTaskList();
}
// built url
String url = CALENDAR_URI + "lists/" + taskListId + "/tasks/" + taskId;
// perform GET request
Map<String, String> headers = getAuthorizationHeaders();
String resp = HttpUtil.get(url, headers);
ObjectMapper mapper = JOM.getInstance();
ObjectNode task = mapper.readValue(resp, ObjectNode.class);
logger.info("getTask task=" + (task != null ?
JOM.getInstance().writeValueAsString(task) : null));
// check for errors
if (task.has("error")) {
ObjectNode error = (ObjectNode)task.get("error");
Integer code = error.has("code") ? error.get("code").asInt() : null;
if (code != null && code.equals(404)) {
throw new JSONRPCException(CODE.NOT_FOUND);
}
throw new JSONRPCException(error);
}
// check if canceled. If so, return null
// TODO: be able to retrieve canceled events?
if (task.has("status") && task.get("status").asText().equals("cancelled")) {
throw new JSONRPCException(CODE.NOT_FOUND);
}
return task;
}
/**
* Create a task
* @param task JSON structure containing the task
* @param taksListId Optional task listid. the default task list is
* used by default
* @return createdTask JSON structure with the created task
*/
@Override
public ObjectNode createTask(@Name("task") ObjectNode task,
@Required(false) @Name("taskListId") String taskListId)
throws Exception {
if (taskListId == null) {
taskListId = getDefaultTaskList();
}
// built url
String url = CALENDAR_URI + "lists/" + taskListId + "/tasks";
// perform POST request
ObjectMapper mapper = JOM.getInstance();
String body = mapper.writeValueAsString(task);
Map<String, String> headers = getAuthorizationHeaders();
headers.put("Content-Type", "application/json");
String resp = HttpUtil.post(url, body, headers);
ObjectNode createdTask = mapper.readValue(resp, ObjectNode.class);
// check for errors
if (createdTask.has("error")) {
ObjectNode error = (ObjectNode)createdTask.get("error");
throw new JSONRPCException(error);
}
logger.info("createTask=" + JOM.getInstance().writeValueAsString(createdTask));
return createdTask;
}
/**
* Update an existing task
* @param task JSON structure containing the task
* (task must have an id)
* @param taksListId Optional task listid. the default task list is
* used by default
* @return updatedTask JSON structure with the updated task
*/
@Override
public ObjectNode updateTask(@Name("task") ObjectNode task,
@Required(false) @Name("taskListId")String taskListId)
throws Exception {
if (taskListId == null) {
taskListId = getDefaultTaskList();
}
// read id from event
String id = task.get("id").asText();
if (id == null) {
throw new Exception("Parameter 'id' missing in task");
}
// built url
String url = CALENDAR_URI + "lists/" + taskListId + "/tasks/" + id;
// perform POST request
ObjectMapper mapper = JOM.getInstance();
String body = mapper.writeValueAsString(task);
Map<String, String> headers = getAuthorizationHeaders();
headers.put("Content-Type", "application/json");
String resp = HttpUtil.put(url, body, headers);
ObjectNode updatedTask = mapper.readValue(resp, ObjectNode.class);
// check for errors
if (updatedTask.has("error")) {
ObjectNode error = (ObjectNode)updatedTask.get("error");
throw new JSONRPCException(error);
}
logger.info("updateTask=" + JOM.getInstance().writeValueAsString(updatedTask)); // TODO: cleanup
return updatedTask;
}
/**
* Delete an existing task
* @param taskId id of the task to be deleted
* @param taksListId Optional task listid. the default task list is
* used by default
*/
@Override
public void deleteTask(@Name("taskId") String taskId,
@Required(false) @Name("taskListId") String taskListId) throws Exception {
if (taskListId == null) {
taskListId = getDefaultTaskList();
}
logger.info("deleteTask taskId=" + taskId + ", taskListId=" + taskListId); // TODO: cleanup
// built url
String url = CALENDAR_URI + "lists/" + taskListId + "/tasks/" + taskId;
// perform POST request
Map<String, String> headers = getAuthorizationHeaders();
String resp = HttpUtil.delete(url, headers);
if (!resp.isEmpty()) {
throw new Exception(resp);
}
}
/**
* Remove all stored data from this agent
*/
public void clear() {
State state = getState();
state.remove("auth");
state.remove("email");
state.remove("name");
state.remove("defaultList");
}
}