Add support for AI.CONFIG (#17)

* Add support for AI.CONFIG

Author: dengliming

src/main/java/com/redislabs/redisai/Command.java

@@ -13,7 +13,8 @@ public enum Command implements ProtocolCommand{
     SCRIPT_GET("AI.SCRIPTGET"),
     SCRIPT_SET("AI.SCRIPTSET"),
     SCRIPT_RUN("AI.SCRIPTRUN"),
-    INFO("AI.INFO");
+    INFO("AI.INFO"),
+    CONFIG("AI.CONFIG");
 
 
     private final byte[] raw;

src/main/java/com/redislabs/redisai/Keyword.java

@@ -5,7 +5,7 @@
 
 public enum Keyword implements ProtocolCommand{
 
-    TENSOR, INPUTS, OUTPUTS, META, VALUES, BLOB, SOURCE, RESETSTAT;
+    TENSOR, INPUTS, OUTPUTS, META, VALUES, BLOB, SOURCE, RESETSTAT, BACKENDSPATH, LOADBACKEND;
 
     private final byte[] raw;
 

src/main/java/com/redislabs/redisai/RedisAI.java

@@ -320,6 +320,34 @@ public boolean resetStat(String key) {
       throw new RedisAIException(ex);
     }
   }
+
+  /**
+   * AI.CONFIG <BACKENDSPATH <path>>
+   *
+   * @return
+   */
+  public boolean setBackendsPath(String path) {
+    try (Jedis conn = getConnection()) {
+      return sendCommand(conn, Command.CONFIG, Keyword.BACKENDSPATH.getRaw(), SafeEncoder.encode(path))
+              .getStatusCodeReply().equals("OK");
+    } catch(JedisDataException ex) {
+      throw new RedisAIException(ex);
+    }
+  }
+
+  /**
+   * AI.CONFIG <LOADBACKEND <backend> <path>>
+   *
+   * @return
+   */
+  public boolean loadBackend(Backend backEnd, String path) {
+    try (Jedis conn = getConnection()) {
+      return sendCommand(conn, Command.CONFIG, Keyword.LOADBACKEND.getRaw(), backEnd.getRaw(), SafeEncoder.encode(path))
+              .getStatusCodeReply().equals("OK");
+    } catch(JedisDataException ex) {
+      throw new RedisAIException(ex);
+    }
+  }
 
   private Jedis getConnection() {
     return pool.getResource();

src/test/java/com/redislabs/redisai/RedisAITest.java

@@ -131,4 +131,17 @@ public void testInfo() {
       // ERR cannot find run info for key
     }
   }
+
+  @Test
+  public void testConfig() {
+    Assert.assertTrue(client.setBackendsPath("/usr/lib/redis/modules/backends/"));
+    try {
+      client.loadBackend(Backend.TF, "notexist/redisai_tensorflow.so");
+      Assert.fail("Should throw JedisDataException");
+    } catch (RedisAIException e) {
+      // ERR error loading backend
+    }
+    // will throw error if backend already loaded
+    Assert.assertTrue(client.loadBackend(Backend.TF, "redisai_tensorflow/redisai_tensorflow.so"));
+  }
 }