1. comments of collector config

2. index creator support options: overwrite, ignore, off

skywalking-collector/skywalking-collector-worker/src/main/java/com/a/eye/skywalking/collector/worker/config/EsConfig.java

@@ -5,6 +5,10 @@ package com.a.eye.skywalking.collector.worker.config;
  */
 public class EsConfig {
 
+    public static final String Create_Overwrite = "overwrite";
+    public static final String Create_Ignore = "ignore";
+    public static final String Create_Off = "off";
+
     public static class Es {
         public static class Cluster {
             public static String name = "";
@@ -16,12 +20,14 @@ public class EsConfig {
         }
 
         public static class Index {
+            public static String create = "";
+
             public static class Shards {
-                public static String number;
+                public static String number = "";
             }
 
-            public static class Replicas{
-                public static String number;
+            public static class Replicas {
+                public static String number = "";
             }
         }
     }

skywalking-collector/skywalking-collector-worker/src/main/java/com/a/eye/skywalking/collector/worker/config/EsConfigProvider.java

@@ -25,6 +25,9 @@ public class EsConfigProvider implements ConfigProvider {
             EsConfig.Es.Cluster.Transport.sniffer = System.getProperty("es.cluster.transport.sniffer");
         }
 
+        if (!StringUtil.isEmpty(System.getProperty("es.index.create"))) {
+            EsConfig.Es.Index.create = System.getProperty("es.index.create");
+        }
         if (!StringUtil.isEmpty(System.getProperty("es.index.shards.number"))) {
             EsConfig.Es.Index.Shards.number = System.getProperty("es.index.shards.number");
         }

skywalking-collector/skywalking-collector-worker/src/main/java/com/a/eye/skywalking/collector/worker/storage/AbstractIndex.java

@@ -5,6 +5,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
 import org.elasticsearch.action.admin.indices.delete.DeleteIndexResponse;
+import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsResponse;
 import org.elasticsearch.action.admin.indices.mapping.put.PutMappingResponse;
 import org.elasticsearch.client.IndicesAdminClient;
 import org.elasticsearch.common.settings.Settings;
@@ -86,5 +87,11 @@ public abstract class AbstractIndex {
         return false;
     }
 
+    final boolean isExists() {
+        IndicesAdminClient client = EsClient.INSTANCE.getClient().admin().indices();
+        IndicesExistsResponse response = client.prepareExists(index()).get();
+        return response.isExists();
+    }
+
     public abstract String index();
 }

skywalking-collector/skywalking-collector-worker/src/main/java/com/a/eye/skywalking/collector/worker/storage/IndexCreator.java

 package com.a.eye.skywalking.collector.worker.storage;
 
+import com.a.eye.skywalking.collector.worker.config.EsConfig;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -16,10 +17,19 @@ public enum IndexCreator {
     private Logger logger = LogManager.getFormatterLogger(IndexCreator.class);
 
     public void create() {
-        Set<AbstractIndex> indexSet = loadIndex();
-        for (AbstractIndex index : indexSet) {
-            index.deleteIndex();
-            index.createIndex();
+        if (!EsConfig.Create_Off.equals(EsConfig.Es.Index.create)) {
+            Set<AbstractIndex> indexSet = loadIndex();
+            for (AbstractIndex index : indexSet) {
+                boolean isExists = index.isExists();
+                if (isExists) {
+                    if (EsConfig.Create_Overwrite.equals(EsConfig.Es.Index.create)) {
+                        index.deleteIndex();
+                        index.createIndex();
+                    }
+                } else {
+                    index.createIndex();
+                }
+            }
         }
     }
 

skywalking-collector/skywalking-collector-worker/src/main/resources/collector.config

+# The remote server should connect to, hostname can be either hostname or IP address.
+# Suggestion: set the real ip address.
 cluster.current.hostname=127.0.0.1
 cluster.current.port=1000
+
+# The roles of this member. List of strings, e.g. roles = A, B
+# In the future, the roles are part of the membership information and can be used by
+# routers or other services to distribute work to certain member types,
+# e.g. front-end and back-end nodes.
+# In this version, all members has same roles, each of them will listen others status,
+# because of network trouble or member jvm crash or every reason led to not reachable,
+# the routers will stop to sending the message to the untouchable member.
 cluster.current.roles=WorkersListener
+
+# Initial contact points of the cluster, e.g. seed_nodes = 127.0.0.1:1000, 127.0.0.1:1001.
+# The nodes to join automatically at startup.
+# When setting akka configuration, it will be change.
+# like: ["akka.tcp://system@127.0.0.1:1000", "akka.tcp://system@127.0.0.1:1001"].
+# This is akka configuration, see: http://doc.akka.io/docs/akka/2.4/general/configuration.html
 cluster.seed_nodes=127.0.0.1:1000,127.0.0.1:1001
 
+# elasticsearch configuration, config/elasticsearch.yml, see cluster.name
 es.cluster.name=CollectorDBCluster
-es.cluster.nodes=127.0.0.1:9300
 es.cluster.transport.sniffer=true
 
+# The elasticsearch nodes of cluster, comma separated, e.g. nodes=ip:port, ip:port
+es.cluster.nodes=127.0.0.1:9300
+
+# Automatic create elasticsearch index
+# Options: overwrite, ignore, off
+# Overwrite: delete the index then create
+# Ignore: just create new index when index not created.
+es.index.create=ignore
 es.index.shards.number=2
 es.index.replicas.number=0
 
+# You can configure a host either as a host name or IP address to identify a specific network
+# interface on which to listen.
+# Be used for web ui get the view data or agent post the trace segment.
 http.hostname=127.0.0.1
+# The TCP/IP port on which the connector listens for connections.
 http.port=7001
+# The contextPath is a URL prefix that identifies which context a HTTP request is destined for.
 http.contextPath=/
 
+# The analysis worker max cache size, when worker data size reach the size,
+# then worker will send all cached data to the next worker and clear the cache.
 cache.analysis.size=1024
+# The persistence worker max cache size, same of "cache.analysis.size" ability.
 cache.persistence.size=1024
 
 WorkerNum.Node.NodeCompAgg.Value=10