com.gravityrd.recengclient.webshop.GravityClient Maven / Gradle / Ivy
/**
* The GravityClient and related classes are used to connect to and communicate with the
* Gravity recommendation engine.
*/
package com.gravityrd.recengclient.webshop;
import com.gravityrd.receng.web.webshop.jsondto.GravityEvent;
import com.gravityrd.receng.web.webshop.jsondto.GravityItem;
import com.gravityrd.receng.web.webshop.jsondto.GravityItemRecommendation;
import com.gravityrd.receng.web.webshop.jsondto.GravityRecEngException;
import com.gravityrd.receng.web.webshop.jsondto.GravityRecommendationContext;
import com.gravityrd.receng.web.webshop.jsondto.GravityScenario;
import com.gravityrd.receng.web.webshop.jsondto.GravityUser;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.Authenticator;
import java.net.HttpURLConnection;
import java.net.PasswordAuthentication;
import java.net.URL;
import java.net.URLEncoder;
import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
/**
* The GravityClient class can be used to send events, item and user information to
* the recommendation engine and get recommendations.
*
* Example usage:
*
*
* public GravityClient createGravityClient() {
* GravityClient client = new GravityClient();
* client.setRemoteUrl("https://saas.gravityrd.com/grrec-CustomerID-war/WebshopServlet");
* client.setUserName("sampleUser");
* client.setPassword("samplePasswd");
* return client;
* }
* GravityClient client = createGravityClient();
* GravityRecommendationContext context = new GravityRecommendationContext();
* context.numberLimit = 1;
* context.scenarioId = "ITEM_PAGE";
* client.getItemRecommendation("user1", context);
*
*/
public final class GravityClient {
private static final ObjectMapper mapper = new ObjectMapper(); // can reuse, share globally
/**
* The version info of the client.
*/
@SuppressWarnings("FieldCanBeLocal")
private final String VERSION = "1.2.0";
/**
* The URL of the server side interface. It has no default value, must be specified.
*/
private String remoteUrl;
/**
* The timeout for the operations in millisecs. The default value is 3000 millisecs.
*/
private int readTimeout = 3000;
/**
* The user name for the http authenticated connection. Leave it blank in case of
* connection without authentication.
*/
private String userName;
/**
* The password for the http authenticated connection. Leave it blank in case of
* connection without authentication.
*/
private String password;
/**
* Query the list of available recommendation scenarios for the backend
* @return array of scenarios
* @throws GravityRecEngException cannot process answer
* @throws IOException cannot connect to server
*/
public GravityScenario[] getScenarioInformation() throws GravityRecEngException, IOException {
return (GravityScenario[]) sendRequest("scenarioInfo", null, null, true, GravityScenario[].class);
}
public String getRemoteUrl() {
return remoteUrl;
}
/**
* Set the URL of the server side interface. It has no default value, must be specified.
* @param remoteUrl the server url provided by Gravity integration team
*/
public void setRemoteUrl(String remoteUrl) {
this.remoteUrl = remoteUrl;
}
public String getUserName() {
return userName;
}
/**
* Set the user name for the http authenticated connection. Leave it blank in case of
* connection without authentication.
* @param userName user authentication name provided by Gravity
*/
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
/**
* Set the password for the http authenticated connection. Leave it blank in case of
* connection without authentication.
* @param password user authentication password provided by Gravity
*/
public void setPassword(String password) {
this.password = password;
}
public int getReadTimeout() {
return readTimeout;
}
/**
* Set the timeout for the operations in millisecs. The default value is 3000 millisecs.
* @param readTimeout wait up to this millisecond for the request answers
*/
public void setReadTimeout(int readTimeout) {
this.readTimeout = readTimeout;
}
/**
* Adds events to the recommendation engine.
*
* @param events The events to add.
* @param async true if the call is asynchronous. An asynchronous call
* returns immediately after an input data checking,
* a synchronous call returns only after the data is saved to database.
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public void addEvents(GravityEvent[] events, boolean async) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
queryStringParams.put("async", Boolean.toString(async));
sendRequest("addEvents", queryStringParams, events, false, null);
}
private Object sendRequest(String methodName, Map queryStringParams, Object requestBody, boolean hasAnswer, Class answerClass) throws GravityRecEngException, IOException {
URL myUrl = new URL(remoteUrl + "/" + methodName + getRequestQueryString(methodName, queryStringParams));
HttpURLConnection connection = (HttpURLConnection) myUrl.openConnection();
connection.setRequestMethod("POST");
connection.addRequestProperty("X-Gravity-RecEng-JavaClient-Webshop-Version", VERSION);
connection.setReadTimeout(readTimeout);
connection.setConnectTimeout(readTimeout);
connection.setDoOutput(true);
Authenticator.setDefault(new UserPasswordAuthenticator(userName, password));
String json = mapper.writeValueAsString(requestBody);
OutputStreamWriter wr = new OutputStreamWriter(connection.getOutputStream());
wr.write(json);
wr.close();
if (connection.getResponseCode() == 500) {
try {
throw mapper.readValue(getBodyAsString(connection.getErrorStream()), GravityRecEngException.class);
} catch (Exception e) {
throw new IllegalStateException(getBodyAsString(connection.getErrorStream()), e);
}
}
connection.getInputStream();
if (hasAnswer) {
try {
return mapper.readValue(getBodyAsString(connection.getInputStream()), answerClass);
} catch (Exception e) {
throw new IllegalStateException(getBodyAsString(connection.getInputStream()), e);
}
} else {
return null;
}
}
private String getRequestQueryString(String methodName, Map queryStringParams) throws UnsupportedEncodingException {
StringBuilder queryString = new StringBuilder();
if (queryStringParams != null) {
for (Entry pair : queryStringParams.entrySet()) {
queryString.append(URLEncoder.encode(pair.getKey(), "UTF-8")).append("=");
queryString.append(URLEncoder.encode(pair.getValue(), "UTF-8")).append("&");
}
}
if (queryString.length() > 0) {
queryString.deleteCharAt(queryString.length() - 1);
queryString.insert(0, "&");
}
return "?method=" + URLEncoder.encode(methodName, "UTF-8") + queryString.toString();
}
private String getBodyAsString(InputStream input) throws IOException {
StringBuilder sb = new StringBuilder();
char[] buffer = new char[2048];
int readChars;
BufferedReader reader = new BufferedReader(new InputStreamReader(input, Charset.forName("UTF-8")));
while ((readChars = reader.read(buffer)) != -1) {
sb.append(buffer, 0, readChars);
}
return sb.toString();
}
/**
* Adds users to the recommendation engine. The existing users will be updated.
* If a user already exists with the specified userId,
* the entire user will be replaced with the new user specified here.
*
* @param users The user to add.
* @param async true if the call is asynchronous. An asynchronous call
* returns immediately after an input data checking,
* a synchronous call returns only after the data is saved to database.
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public void addUsers(GravityUser[] users, boolean async) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
queryStringParams.put("async", Boolean.toString(async));
sendRequest("addUsers", queryStringParams, users, false, null);
}
/**
* Adds items to the recommendation engine.
* If an item already exists with the specified itemId,
* the entire item along with its NameValue pairs will be replaced to the new item specified here.
*
* @param items The items to add
* @param async true if the call is asynchronous. An asynchronous call
* returns immediately after an input data checking,
* a synchronous call returns only after the data is saved to
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer filesdatabase.
*/
public void addItems(GravityItem[] items, boolean async) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
queryStringParams.put("async", Boolean.toString(async));
sendRequest("addItems", queryStringParams, items, false, null);
}
/**
* Returns a list of recommended items, based on the given context parameters.
*
* @param userId The identifier of the logged in user. If no user is logged in, null should be specified.
* @param cookieId It should be a permanent identifier for the end users computer, preserving its value across browser sessions.
* It should be always specified.
* @param context Additional information which describes the actual scenario.
* @return An object containing the recommended items and other information about the recommendation.
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public GravityItemRecommendation getItemRecommendation(String userId, String cookieId, GravityRecommendationContext context) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
if (userId != null) {
queryStringParams.put("userId", userId);
}
if (cookieId != null) {
queryStringParams.put("cookieId", cookieId);
}
return (GravityItemRecommendation) sendRequest("getItemRecommendation",
queryStringParams, context, true, GravityItemRecommendation.class);
}
/**
* Given the userId and the cookieId, we can request recommendations for multiple scenarios (described by the context).
* This function returns lists of recommended items for each of the given scenarios in an array.
*
* @param userId The identifier of the logged in user. If no user is logged in, null should be specified.
* @param cookieId It should be a permanent identifier for the end users computer, preserving its value across browser sessions.
* It should be always specified.
* @param context Additional Array of information which describes the actual scenarios.
* @return An Array containing the recommended items for each scenario with other information about the recommendation.
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public GravityItemRecommendation[] getItemRecommendationBulk(String userId, String cookieId, GravityRecommendationContext[] context) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
if (userId != null) {
queryStringParams.put("userId", userId);
}
if (cookieId != null) {
queryStringParams.put("cookieId", cookieId);
}
return (GravityItemRecommendation[]) sendRequest("getItemRecommendationBulk",
queryStringParams, context, true, GravityItemRecommendation[].class);
}
/**
* Simple test function to test without side effects whether the service is alive.
* @param name a test string
* @return "Hello " + name* @throws IOException if cannot connect
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public String test(String name) throws GravityRecEngException, IOException {
HashMap queryStringParams = new HashMap<>();
queryStringParams.put("name", name);
return (String) sendRequest("test", queryStringParams, name, true, String.class);
}
/**
* Simple test function to test throwing an exception.
* @throws IOException if cannot connect
* @throws GravityRecEngException if cannot process the answer files
*/
public void testException() throws GravityRecEngException, IOException {
sendRequest("testException", null, null, true, null);
}
private static class UserPasswordAuthenticator extends Authenticator {
private final String username, password;
public UserPasswordAuthenticator(String user, String pwd) {
username = user;
password = pwd;
}
@Override
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(username, password.toCharArray());
}
}
}
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