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阿新 • • 發佈:2021-02-03
技術標籤:SpingCloud Alibabasentinel資料持久化
文章目錄
我們可以通過Dashboard來為每個Sentinel客戶端設定各種各樣的規則,但是這裡有一個問題,就是這些規則預設是存放在記憶體中,極不穩定,所以需要將其持久化。本地檔案資料來源會定時輪詢檔案的變更,讀取規則。這樣我們既可以在應用本地直接修改檔案來更新規則,也可以通過 Sentinel 控制檯推送規則。以本地檔案資料來源為例,推送過程如下圖所示:
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首先 Sentinel 控制檯通過 API 將規則推送至客戶端並更新到記憶體中,接著註冊的寫資料來源會將新的規則儲存到本地的檔案中。
FilePersistence配置類
import com.alibaba.csp.sentinel.command.handler.ModifyParamFlowRulesCommandHandler;
import com.alibaba.csp.sentinel.datasource.*;
import com.alibaba.csp.sentinel.init.InitFunc;
import com.alibaba.csp.sentinel.slots. block.authority.AuthorityRule;
import com.alibaba.csp.sentinel.slots.block.authority.AuthorityRuleManager;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRule;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeRuleManager;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
import com.alibaba.csp.sentinel.slots.block.flow.param.ParamFlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.param.ParamFlowRuleManager;
import com.alibaba.csp.sentinel.slots.system.SystemRule;
import com.alibaba.csp.sentinel.slots.system.SystemRuleManager;
import com.alibaba.csp.sentinel.transport.util.WritableDataSourceRegistry;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import org.springframework.beans.factory.annotation.Value;
import java.io.File;
import java.io.IOException;
import java.util.List;
public class FilePersistence implements InitFunc {
@Value("spring.application:name")
private String appcationName;
@Override
public void init() throws Exception {
//指定檔案生成目錄
String ruleDir = System.getProperty("user.home") + "/sentinelrules/" + appcationName;
String flowRulePath = ruleDir + "/flow-rule.json";
String degradeRulePath = ruleDir + "/degrade-rule.json";
String systemRulePath = ruleDir + "/system-rule.json";
String authorityRulePath =
ruleDir + "/authority-rule.json";
String paramFlowRulePath = ruleDir + "/param-flow-rule.json";
this.mkdirIfNotExits(ruleDir);
this.createFileIfNotExits(flowRulePath);
this.createFileIfNotExits(degradeRulePath);
this.createFileIfNotExits(systemRulePath);
this.createFileIfNotExits(authorityRulePath);
this.createFileIfNotExits(paramFlowRulePath);
// 流控規則
ReadableDataSource<String, List<FlowRule>> flowRuleRDS = new FileRefreshableDataSource<>(flowRulePath, flowRuleListParser);
FlowRuleManager.register2Property(flowRuleRDS.getProperty());
WritableDataSource<List<FlowRule>> flowRuleWDS = new
FileWritableDataSource<>(
flowRulePath,
this::encodeJson
);
WritableDataSourceRegistry.registerFlowDataSource(flowRuleWDS);
// 降級規則
ReadableDataSource<String, List<DegradeRule>> degradeRuleRDS = new
FileRefreshableDataSource<>(
degradeRulePath,
degradeRuleListParser
);
DegradeRuleManager.register2Property(degradeRuleRDS.getProperty());
WritableDataSource<List<DegradeRule>> degradeRuleWDS = new
FileWritableDataSource<>(
degradeRulePath,
this::encodeJson
);
WritableDataSourceRegistry.registerDegradeDataSource(degradeRuleWDS);
// 系統規則
ReadableDataSource<String, List<SystemRule>> systemRuleRDS = new
FileRefreshableDataSource<>(
systemRulePath,
systemRuleListParser);
SystemRuleManager.register2Property(systemRuleRDS.getProperty());
WritableDataSource<List<SystemRule>> systemRuleWDS = new
FileWritableDataSource<>(
systemRulePath,
this::encodeJson);
WritableDataSourceRegistry.registerSystemDataSource(systemRuleWDS);
// 授權規則
ReadableDataSource<String, List<AuthorityRule>> authorityRuleRDS = new
FileRefreshableDataSource<>(
authorityRulePath,
authorityRuleListParser
);
AuthorityRuleManager.register2Property(authorityRuleRDS.getProperty());
WritableDataSource<List<AuthorityRule>> authorityRuleWDS = new
FileWritableDataSource<>(
authorityRulePath,
this::encodeJson
);
WritableDataSourceRegistry.registerAuthorityDataSource(authorityRuleWDS);
// 熱點引數規則
ReadableDataSource<String, List<ParamFlowRule>> paramFlowRuleRDS = new
FileRefreshableDataSource<>(
paramFlowRulePath,
paramFlowRuleListParser
);
ParamFlowRuleManager.register2Property(paramFlowRuleRDS.getProperty());
WritableDataSource<List<ParamFlowRule>> paramFlowRuleWDS = new
FileWritableDataSource<>(paramFlowRulePath,
this::encodeJson
);
ModifyParamFlowRulesCommandHandler.setWritableDataSource(paramFlowRuleWDS);
}
private Converter<String, List<FlowRule>> flowRuleListParser = source ->
JSON.parseObject(source, new TypeReference<List<FlowRule>>() {
});
private Converter<String, List<DegradeRule>> degradeRuleListParser = source
-> JSON.parseObject(
source,
new TypeReference<List<DegradeRule>>() {
});
private Converter<String, List<SystemRule>> systemRuleListParser = source ->
JSON.parseObject(
source,
new TypeReference<List<SystemRule>>() {
});
private Converter<String, List<AuthorityRule>> authorityRuleListParser =
source -> JSON.parseObject(
source,
new TypeReference<List<AuthorityRule>>() {
});
private Converter<String, List<ParamFlowRule>> paramFlowRuleListParser =
source -> JSON.parseObject(
source,
new TypeReference<List<ParamFlowRule>>() {
});
private void mkdirIfNotExits(String filePath) throws IOException {
File file = new File(filePath);
if (!file.exists()) {
file.mkdirs();
}
}
private void createFileIfNotExits(String filePath) throws IOException {
File file = new File(filePath);
if (!file.exists()) {
file.createNewFile();
}
}
private <T> String encodeJson(T t) {
return JSON.toJSONString(t);
}
}
新增配置
- 在resources下建立配置目錄
META-INF/services
,然後新增檔案
com.alibaba.csp.sentinel.init.InitFunc
- 在檔案中新增配置類的全路徑,剛才新增的配置類
com.xxx.config.FilePersistence
然後在sentinel客戶端新增限流、降級等配置重新啟動服務,之前保留的配置還在
這個目錄就是我們在專案中指定的生成目錄做的持久化檔案
-