Log Service使用Shard控制LogStore或MetricStore讀寫資料的能力，資料必定儲存在某一個Shard中。本文通過程式碼範例介紹如何查詢、分裂、合并Shard。
前提條件
您已完成以下操作：
已安裝Log ServiceJava SDK。具體操作，請參見安裝Java SDK。
已建立Project、標準型Logstore。具體操作，請參見管理Project、建立基礎LogStore。
分裂Shard、合并Shard需要該Shard狀態為readwrite,Shard狀態為readonly分裂或者合并會報錯。
注意事項
本樣本以華東1（杭州）的公網Endpoint為例，其公網Endpoint為https://cn-hangzhou.log.aliyuncs.com。
如果您通過與Project同地區的其他阿里雲產品訪問Log Service，請使用內網Endpointhttps://cn-hangzhou-intranet.log.aliyuncs.com。
關於Log Service支援的地區與Endpoint的對應關係，請參見服務入口。
查詢Shard範例程式碼
以下代碼用於查詢指定LogStore的Shard資訊。
import com.aliyun.openservices.log.Client;
import com.aliyun.openservices.log.common.Shard;
import com.aliyun.openservices.log.exception.LogException;
import com.aliyun.openservices.log.response.ListShardResponse;
public class ListShards {
public static void main(String[] args) throws LogException {
// 本樣本從環境變數中擷取AccessKey ID和AccessKey Secret。
String accessId = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID");
String accessKey = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET");
// 輸入Project名稱。
String projectName = "ali-test-project";
// 輸入LogStore名稱。
String logstoreName = "ali-test-logstore";
// 設定Log Service的服務存取點。此處以杭州為例，其它地區請根據實際情況填寫。
String host = "https://cn-hangzhou.log.aliyuncs.com";
// 建立Log ServiceClient。
Client client = new Client(host, accessId, accessKey);
try {
System.out.println("ready to list shards");
// 查詢指定LogStore的所有Shard。
ListShardResponse response = client.ListShard(projectName, logstoreName);
for(Shard shard : response.GetShards()){
System.out.println("Shard ID is :" + shard.getShardId());
System.out.println("Shard status is :" + shard.getStatus());
System.out.println("Shard begin key is :" + shard.getInclusiveBeginKey());
System.out.println("Shard end key is :" + shard.getExclusiveEndKey());
System.out.println("Shard create time is :" + shard.getCreateTime());
}
System.out.println(String.format("list shards of %s success", logstoreName));
} catch (LogException e) {
System.out.println("LogException e :" + e.toString());
System.out.println("error code :" + e.GetErrorCode());
System.out.println("error message :" + e.GetErrorMessage());
throw e;
}
}
}預期結果如下：
ready to list shards
Shard ID is :0
Shard status is :readwrite
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard create time is :1667810747
Shard ID is :1
Shard status is :readwrite
Shard begin key is :7f000000000000000000000000000000
Shard end key is :ffffffffffffffffffffffffffffffff
Shard create time is :1667810747
list shards of ali-test-logstore success分裂Shard範例程式碼
以下代碼用於分裂指定LogStore的Shard。
import com.aliyun.openservices.log.Client;
import com.aliyun.openservices.log.common.Shard;
import com.aliyun.openservices.log.exception.LogException;
import com.aliyun.openservices.log.response.ListShardResponse;
import java.util.concurrent.TimeUnit;
public class SplitShard {
public static void main(String[] args) throws LogException {
// 本樣本從環境變數中擷取AccessKey ID和AccessKey Secret。
String accessId = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID");
String accessKey = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET");
// 輸入Project名稱。
String projectName = "ali-test-project";
// 輸入LogStore名稱。
String logstoreName = "ali-test-logstore";
// 設定Log Service的服務存取點。此處以杭州為例，其它地區請根據實際情況填寫。
String host = "https://cn-hangzhou.log.aliyuncs.com";
// 建立Log ServiceClient。
Client client = new Client(host, accessId, accessKey);
try {
System.out.println("ready to list shard");
// 分裂之前先查看所有Shard。
ListShardResponse response = client.ListShard(projectName, logstoreName);
for(Shard shard : response.GetShards()){
System.out.println("Shard ID is :" + shard.getShardId());
System.out.println("Shard status is :" + shard.getStatus());
System.out.println("Shard begin key is :" + shard.getInclusiveBeginKey());
System.out.println("Shard end key is :" + shard.getExclusiveEndKey());
}
System.out.println("ready to split shard");
// 分裂Shard 0。
client.SplitShard(projectName, logstoreName, 0, "3f000000000000000000000000000000");
// 等待60秒後再查詢Shard。
TimeUnit.SECONDS.sleep(60);
System.out.println(String.format("split shards of %s success", logstoreName));
// 分裂之後再查看所有Shard。
ListShardResponse response1 = client.ListShard(projectName, logstoreName);
for(Shard shard1 : response1.GetShards()){
System.out.println("Shard ID is :" + shard1.getShardId());
System.out.println("Shard status is :" + shard1.getStatus());
System.out.println("Shard begin key is :" + shard1.getInclusiveBeginKey());
System.out.println("Shard end key is :" + shard1.getExclusiveEndKey());
}
} catch (LogException e) {
System.out.println("LogException e :" + e.toString());
System.out.println("error code :" + e.GetErrorCode());
System.out.println("error message :" + e.GetErrorMessage());
throw e;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}預期結果如下：
ready to list shard
Shard ID is :0
Shard status is :readwrite
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard ID is :1
Shard status is :readwrite
Shard begin key is :7f000000000000000000000000000000
Shard end key is :ffffffffffffffffffffffffffffffff
ready to split shard
split shards of ali-test-logstore success
Shard ID is :2
Shard status is :readwrite
Shard begin key is :00000000000000000000000000000000
Shard end key is :3f000000000000000000000000000000
Shard ID is :3
Shard status is :readwrite
Shard begin key is :3f000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard ID is :1
Shard status is :readwrite
Shard begin key is :7f000000000000000000000000000000
Shard end key is :ffffffffffffffffffffffffffffffff
Shard ID is :0
Shard status is :readonly
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000合并Shard範例程式碼
以下代碼用於合并指定LogStore的Shard。
import com.aliyun.openservices.log.Client;
import com.aliyun.openservices.log.common.Shard;
import com.aliyun.openservices.log.exception.LogException;
import com.aliyun.openservices.log.response.ListShardResponse;
import java.util.concurrent.TimeUnit;
public class MergeShard {
public static void main(String[] args) throws LogException {
// 本樣本從環境變數中擷取AccessKey ID和AccessKey Secret。
String accessId = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID");
String accessKey = System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET");
// 輸入Project名稱。
String projectName = "ali-test-project";
// 輸入LogStore名稱。
String logstoreName = "ali-test-logstore";
// 設定Log Service的服務存取點。此處以杭州為例，其它地區請根據實際情況填寫。
String host = "https://cn-hangzhou.log.aliyuncs.com";
// 建立Log ServiceClient。
Client client = new Client(host, accessId, accessKey);
try {
System.out.println("ready to list shard");
// 合并之前先查看所有Shard。
ListShardResponse response = client.ListShard(projectName, logstoreName);
for(Shard shard : response.GetShards()){
System.out.println("Shard ID is :" + shard.getShardId());
System.out.println("Shard status is :" + shard.getStatus());
System.out.println("Shard begin key is :" + shard.getInclusiveBeginKey());
System.out.println("Shard end key is :" + shard.getExclusiveEndKey());
}
System.out.println("ready to merge shard");
// 將Shard 2和3進行合并。服務端會自動找到相鄰的下一個Shard進行合并。
client.MergeShards(projectName, logstoreName, 2);
// 等待60秒後再查詢Shard。
TimeUnit.SECONDS.sleep(60);
System.out.println(String.format("merge shards of %s success", logstoreName));
// 合并之後再查看所有Shard。
ListShardResponse response1 = client.ListShard(projectName, logstoreName);
for(Shard shard1 : response1.GetShards()){
System.out.println("Shard ID is :" + shard1.getShardId());
System.out.println("Shard status is :" + shard1.getStatus());
System.out.println("Shard begin key is :" + shard1.getInclusiveBeginKey());
System.out.println("Shard end key is :" + shard1.getExclusiveEndKey());
}
} catch (LogException e) {
System.out.println("LogException e :" + e.toString());
System.out.println("error code :" + e.GetErrorCode());
System.out.println("error message :" + e.GetErrorMessage());
throw e;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}預期結果如下：
ready to list shard
Shard ID is :2
Shard status is :readwrite
Shard begin key is :00000000000000000000000000000000
Shard end key is :3f000000000000000000000000000000
Shard ID is :3
Shard status is :readwrite
Shard begin key is :3f000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard ID is :1
Shard status is :readwrite
Shard begin key is :7f000000000000000000000000000000
Shard end key is :ffffffffffffffffffffffffffffffff
Shard ID is :0
Shard status is :readonly
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
ready to merge shard
merge shards of ali-test-logstore success
Shard ID is :4
Shard status is :readwrite
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard ID is :1
Shard status is :readwrite
Shard begin key is :7f000000000000000000000000000000
Shard end key is :ffffffffffffffffffffffffffffffff
Shard ID is :0
Shard status is :readonly
Shard begin key is :00000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000
Shard ID is :2
Shard status is :readonly
Shard begin key is :00000000000000000000000000000000
Shard end key is :3f000000000000000000000000000000
Shard ID is :3
Shard status is :readonly
Shard begin key is :3f000000000000000000000000000000
Shard end key is :7f000000000000000000000000000000相關文檔
在調用API介面過程中，若服務端返回結果中包含錯誤資訊，則表示調用API介面失敗。您可以參考API錯誤碼對照表尋找對應的解決方案。更多資訊，請參見API錯誤處理對照表。
Log Service除自研的SDK外，還支援公用的阿里雲SDK，關於阿里雲SDK的使用方式，請參見Log Service_SDK中心-阿里雲OpenAPI開發人員門戶。
為滿足越來越多的自動化Log Service配置需求，Log Service提供命令列工具CLI（Command Line Interface）。更多資訊，請參見Log Service命令列工具CLI。
關於Shard API介面說明，請參見如下：
更多範例程式碼，請參見Aliyun Log Java SDK on GitHub。