1 /*******************************************************************************
2 * ============LICENSE_START==================================================
4 * * ===========================================================================
5 * * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
6 * * ===========================================================================
7 * * Licensed under the Apache License, Version 2.0 (the "License");
8 * * you may not use this file except in compliance with the License.
9 * * You may obtain a copy of the License at
11 * * http://www.apache.org/licenses/LICENSE-2.0
13 * * Unless required by applicable law or agreed to in writing, software
14 * * distributed under the License is distributed on an "AS IS" BASIS,
15 * * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * * See the License for the specific language governing permissions and
17 * * limitations under the License.
18 * * ============LICENSE_END====================================================
20 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
22 ******************************************************************************/
25 package org.onap.dmaap.datarouter.node;
27 import java.io.BufferedReader;
28 import java.io.FileOutputStream;
29 import java.io.FileReader;
30 import java.io.OutputStream;
31 import java.util.Hashtable;
32 import java.util.Timer;
35 * Track redirections of subscriptions
37 public class RedirManager {
39 private Hashtable<String, String> sid2primary = new Hashtable<String, String>();
40 private Hashtable<String, String> sid2secondary = new Hashtable<String, String>();
41 private String redirfile;
42 RateLimitedOperation op;
45 * Create a mechanism for maintaining subscription redirections.
47 * @param redirfile The file to store the redirection information.
48 * @param mininterval The minimum number of milliseconds between writes to the redirection
50 * @param timer The timer thread used to run delayed file writes.
52 public RedirManager(String redirfile, long mininterval, Timer timer) {
53 this.redirfile = redirfile;
54 op = new RateLimitedOperation(mininterval, timer) {
57 StringBuffer sb = new StringBuffer();
58 for (String s : sid2primary.keySet()) {
59 sb.append(s).append(' ').append(sid2primary.get(s)).append(' ')
60 .append(sid2secondary.get(s)).append('\n');
62 try (OutputStream os = new FileOutputStream(RedirManager.this.redirfile)) {
63 os.write(sb.toString().getBytes());
65 } catch (Exception e) {
71 try (BufferedReader br = new BufferedReader(new FileReader(redirfile))) {
72 while ((s = br.readLine()) != null) {
74 String[] sx = s.split(" ");
75 if (s.startsWith("#") || sx.length != 3) {
78 sid2primary.put(sx[0], sx[1]);
79 sid2secondary.put(sx[0], sx[2]);
82 } catch (Exception e) {
83 // missing file is normal
88 * Set up redirection. If a request is to be sent to subscription ID sid, and that is
89 * configured to go to URL primary, instead, go to secondary.
91 * @param sid The subscription ID to be redirected
92 * @param primary The URL associated with that subscription ID
93 * @param secondary The replacement URL to use instead
95 public synchronized void redirect(String sid, String primary, String secondary) {
96 sid2primary.put(sid, primary);
97 sid2secondary.put(sid, secondary);
102 * Cancel redirection. If a request is to be sent to subscription ID sid, send it to its
105 * @param sid The subscription ID to remove from the table.
107 public synchronized void forget(String sid) {
108 sid2primary.remove(sid);
109 sid2secondary.remove(sid);
114 * Look up where to send a subscription. If the primary has changed or there is no redirection,
115 * use the primary. Otherwise, redirect to the secondary URL.
117 * @param sid The subscription ID to look up.
118 * @param primary The configured primary URL.
119 * @return The destination URL to really use.
121 public synchronized String lookup(String sid, String primary) {
122 String oprim = sid2primary.get(sid);
123 if (primary.equals(oprim)) {
124 return (sid2secondary.get(sid));
125 } else if (oprim != null) {
132 * Is a subscription redirected?
134 public synchronized boolean isRedirected(String sid) {
135 return (sid != null && sid2secondary.get(sid) != null);