From 9eb2ac899e1fb05248c75af8a0809ca7db568956 Mon Sep 17 00:00:00 2001
From: Jan Vales <jan@jvales.net>
Date: Fri, 30 Mar 2018 21:58:06 +0200
Subject: [PATCH] [1.5] redis ^.^

---
 .../java/dst/ass1/kv/impl/SessionManager.java | 73 +++++++++++++++++++
 .../ass1/kv/impl/SessionManagerFactory.java   |  9 +--
 2 files changed, 76 insertions(+), 6 deletions(-)
 create mode 100644 ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManager.java

diff --git a/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManager.java b/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManager.java
new file mode 100644
index 0000000..02fc964
--- /dev/null
+++ b/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManager.java
@@ -0,0 +1,73 @@
+package dst.ass1.kv.impl;
+
+import dst.ass1.kv.ISessionManager;
+import dst.ass1.kv.SessionCreationFailedException;
+import dst.ass1.kv.SessionNotFoundException;
+import redis.clients.jedis.Jedis;
+import redis.clients.jedis.Transaction;
+
+import java.util.UUID;
+
+public class SessionManager implements ISessionManager {
+    // "sUser:${userId}" -> UUID - Reverse-sessiondata-userId-mapping.
+    private final static String SUSER = "sUser:";
+    //  "sData:${UUID}" -> hashmap - Sessiondata.
+    private final static String SDATA = "sData:";
+
+    private final Jedis jedis; // no lightsabers :(
+
+    public SessionManager(String host, int port) {
+        jedis = new Jedis(host, port);
+    }
+
+    @Override
+    public String createSession(Long userId, int timeToLive) throws SessionCreationFailedException {
+        jedis.del(SUSER + userId.toString());
+        return requireSession(userId, timeToLive);
+    }
+
+    @Override
+    public void setSessionVariable(String sessionId, String key, String value) throws SessionNotFoundException {
+        if (!jedis.exists(SDATA + sessionId)) throw new SessionNotFoundException("Unknown sessionId:" + sessionId);
+        jedis.hset(SDATA + sessionId, key, value);
+    }
+
+    @Override
+    public String getSessionVariable(String sessionId, String key) throws SessionNotFoundException {
+        if (!jedis.exists(SDATA + sessionId)) throw new SessionNotFoundException("Unknown sessionId:" + sessionId);
+        return jedis.hget(SDATA + sessionId, key);
+    }
+
+    @Override
+    public Long getUserId(String sessionId) throws SessionNotFoundException {
+        if (!jedis.exists(SDATA + sessionId)) throw new SessionNotFoundException("Unknown sessionId:" + sessionId);
+        return Long.valueOf(jedis.hget(SDATA + sessionId, "userId"));
+    }
+
+    @Override
+    public int getTimeToLive(String sessionId) throws SessionNotFoundException {
+        if (!jedis.exists(SDATA + sessionId)) throw new SessionNotFoundException("Unknown sessionId:" + sessionId);
+        return jedis.ttl(SDATA + sessionId).intValue();
+    }
+
+    @Override
+    public String requireSession(Long userId, int timeToLive) throws SessionCreationFailedException {
+        String uuid = jedis.get(SUSER + userId.toString());
+        if (uuid == null) {
+            uuid = UUID.randomUUID().toString();
+            jedis.watch(SUSER + userId.toString());
+            Transaction t = jedis.multi();
+            t.set(SUSER + userId.toString(), uuid);
+            t.expire(SUSER + userId.toString(), timeToLive);
+            t.hset(SDATA + uuid, "userId", userId.toString());
+            t.expire(SDATA + uuid, timeToLive);
+            t.exec();
+        }
+        return uuid;
+    }
+
+    @Override
+    public void close() {
+        jedis.close();
+    }
+}
diff --git a/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManagerFactory.java b/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManagerFactory.java
index 4b0a721..2177f26 100644
--- a/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManagerFactory.java
+++ b/ass1-kv/src/main/java/dst/ass1/kv/impl/SessionManagerFactory.java
@@ -1,17 +1,14 @@
 package dst.ass1.kv.impl;
 
-import java.util.Properties;
-
 import dst.ass1.kv.ISessionManager;
 import dst.ass1.kv.ISessionManagerFactory;
 
+import java.util.Properties;
+
 public class SessionManagerFactory implements ISessionManagerFactory {
 
     @Override
     public ISessionManager createSessionManager(Properties properties) {
-        // TODO
-        // read "redis.host" and "redis.port" from the properties
-
-        return null;
+        return new SessionManager(properties.getProperty("redis.host"), Integer.parseInt(properties.getProperty("redis.port")));
     }
 }
-- 
2.43.0