Impl learner for jraft, #8

jraft-core/src/main/java/com/alipay/sofa/jraft/CliService.java

@@ -75,6 +75,45 @@ public interface CliService extends Lifecycle<CliOptions> {
      */
     Status resetPeer(final String groupId, final PeerId peer, final Configuration newPeers);
 
+    /**
+     * Add some new learners into the replicating group which consists of |conf|.
+     * return OK status when success.
+     *
+     * @param groupId  the raft group id
+     * @param conf     current configuration
+     * @param learners learner peers to add
+     * @return operation status
+     * @since 1.3.0
+     *
+     */
+    Status addLearners(final String groupId, final Configuration conf, final List<PeerId> learners);
+
+    /**
+     * Remove some learners from the replicating group which consists of |conf|.
+     * return OK status when success.
+     *
+     * @param groupId  the raft group id
+     * @param conf     current configuration
+     * @param learners learner peers to remove
+     * @return operation status
+     * @since 1.3.0
+     *
+     */
+    Status removeLearners(final String groupId, final Configuration conf, final List<PeerId> learners);
+
+    /**
+     * Update learners set in the replicating group which consists of |conf|.
+     * return OK status when success.
+     *
+     * @param groupId  the raft group id
+     * @param conf     current configuration
+     * @param learners learner peers to set
+     * @return operation status
+     * @since 1.3.0
+     *
+     */
+    Status resetLearners(final String groupId, final Configuration conf, final List<PeerId> learners);
+
     /**
      * Transfer the leader of the replication group to the target peer
      *
@@ -121,6 +160,25 @@ public interface CliService extends Lifecycle<CliOptions> {
      */
     List<PeerId> getAlivePeers(final String groupId, final Configuration conf);
 
+    /**
+     * Ask all learners of the replication group.
+     *
+     * @param groupId the raft group id
+     * @param conf    target peers configuration
+     * @return all learners of the replication group
+     * @since 1.3.0
+     */
+    List<PeerId> getLearners(final String groupId, final Configuration conf);
+
+    /**
+     * Ask all alive learners of the replication group.
+     *
+     * @param groupId the raft group id
+     * @param conf    target peers configuration
+     * @return all alive learners of the replication group
+     */
+    List<PeerId> getAliveLearners(final String groupId, final Configuration conf);
+
     /**
      * Balance the number of leaders.
      *

jraft-core/src/main/java/com/alipay/sofa/jraft/Node.java

@@ -135,18 +135,41 @@ public interface Node extends Lifecycle<NodeOptions>, Describer {
     List<PeerId> listPeers();
 
     /**
-     * List all alive peers of this raft group, only leader returns.
+     * List all alive peers of this raft group, only leader returns.</p>
      *
      * [NOTE] <strong>list_alive_peers is just a transient data (snapshot)
      * and a short-term loss of response by the follower will cause it to
      * temporarily not exist in this list.</strong>
      *
      * @return the alive peer list
-     *
      * @since 1.2.6
      */
     List<PeerId> listAlivePeers();
 
+    /**
+     * List all learners of this raft group, only leader returns.</p>
+     *
+     * [NOTE] <strong>when listLearners concurrency with {@link #addLearners(List, Closure)}/{@link #removeLearners(List, Closure)}/{@link #resetLearners(List, Closure)},
+     * maybe return peers is staled.  Because {@link #addLearners(List, Closure)}/{@link #removeLearners(List, Closure)}/{@link #resetLearners(List, Closure)}
+     * immediately modify configuration in memory</strong>
+     *
+     * @return the learners set
+     * @since 1.3.0
+     */
+    List<PeerId> listLearners();
+
+    /**
+     * List all alive learners of this raft group, only leader returns.</p>
+     *
+     * [NOTE] <strong>when listAliveLearners concurrency with {@link #addLearners(List, Closure)}/{@link #removeLearners(List, Closure)}/{@link #resetLearners(List, Closure)},
+     * maybe return peers is staled.  Because {@link #addLearners(List, Closure)}/{@link #removeLearners(List, Closure)}/{@link #resetLearners(List, Closure)}
+     * immediately modify configuration in memory</strong>
+     *
+     * @return the  alive learners set
+     * @since 1.3.0
+     */
+    List<PeerId> listAliveLearners();
+
     /**
      * Add a new peer to the raft group. done.run() would be invoked after this
      * operation finishes, describing the detailed result.
@@ -182,9 +205,41 @@ public interface Node extends Lifecycle<NodeOptions>, Describer {
      * availability.
      * Notice that neither consistency nor consensus are guaranteed in this
      * case, BE CAREFULE when dealing with this method.
+     *
+     * @param newPeers new peers
      */
     Status resetPeers(final Configuration newPeers);
 
+    /**
+     * Add some new learners to the raft group. done.run() will be invoked after this
+     * operation finishes, describing the detailed result.
+     *
+     * @param learners learners to add
+     * @param done     callback
+     * @since 1.3.0
+     */
+    void addLearners(final List<PeerId> learners, final Closure done);
+
+    /**
+     * Remove some learners from the raft group. done.run() will be invoked after this
+     * operation finishes, describing the detailed result.
+     *
+     * @param learners learners to remove
+     * @param done     callback
+     * @since 1.3.0
+     */
+    void removeLearners(final List<PeerId> learners, final Closure done);
+
+    /**
+     * Reset learners in the raft group. done.run() will be invoked after this
+     * operation finishes, describing the detailed result.
+     *
+     * @param learners learners to set
+     * @param done     callback
+     * @since 1.3.0
+     */
+    void resetLearners(final List<PeerId> learners, final Closure done);
+
     /**
      * Start a snapshot immediately if possible. done.run() would be invoked when
      * the snapshot finishes, describing the detailed result.

jraft-core/src/main/java/com/alipay/sofa/jraft/ReplicatorGroup.java

@@ -20,6 +20,7 @@
 
 import com.alipay.sofa.jraft.closure.CatchUpClosure;
 import com.alipay.sofa.jraft.conf.ConfigurationEntry;
+import com.alipay.sofa.jraft.core.ReplicatorType;
 import com.alipay.sofa.jraft.entity.NodeId;
 import com.alipay.sofa.jraft.entity.PeerId;
 import com.alipay.sofa.jraft.option.ReplicatorGroupOptions;
@@ -45,6 +46,15 @@ public interface ReplicatorGroup extends Describer {
      */
     boolean init(final NodeId nodeId, final ReplicatorGroupOptions opts);
 
+    /**
+     * Adds a replicator for follower({@link ReplicatorType#Follower}).
+     * @see #addReplicator(PeerId, ReplicatorType)
+     *
+     * @param peer target peer
+     * @return true on success
+     */
+    boolean addReplicator(final PeerId peer);
+
     /**
      * Add a replicator attached with |peer|
      * will be a notification when the replicator catches up according to the
@@ -53,10 +63,11 @@ public interface ReplicatorGroup extends Describer {
      * immediately, and might call Node#stepDown which might have race with
      * the caller, you should deal with this situation.
      *
-     * @param peer target peer
+     * @param peer           target peer
+     * @param replicatorType replicator type
      * @return true on success
      */
-    boolean addReplicator(final PeerId peer);
+    boolean addReplicator(final PeerId peer, ReplicatorType replicatorType);
 
     /**
      * Send heartbeat to a peer.