content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.alibaba.csp.sentinel.dashboard.controller;
  
  import java.util.Date;
  import java.util.List;
  import java.util.Optional;
  import java.util.concurrent.CompletableFuture;
  import java.util.concurrent.ExecutionException;
  
  import com.alibaba.csp.sentinel.dashboard.auth.AuthAction;
  import com.alibaba.csp.sentinel.dashboard.client.CommandNotFoundException;
  import com.alibaba.csp.sentinel.dashboard.client.SentinelApiClient;
  import com.alibaba.csp.sentinel.dashboard.discovery.AppManagement;
  import com.alibaba.csp.sentinel.dashboard.discovery.MachineInfo;
  import com.alibaba.csp.sentinel.dashboard.auth.AuthService;
  import com.alibaba.csp.sentinel.dashboard.auth.AuthService.PrivilegeType;
  import com.alibaba.csp.sentinel.slots.block.RuleConstant;
  import com.alibaba.csp.sentinel.util.StringUtil;
  import com.alibaba.csp.sentinel.dashboard.datasource.entity.SentinelVersion;
  import com.alibaba.csp.sentinel.dashboard.datasource.entity.rule.ParamFlowRuleEntity;
  import com.alibaba.csp.sentinel.dashboard.domain.Result;
  import com.alibaba.csp.sentinel.dashboard.repository.rule.RuleRepository;
  import com.alibaba.csp.sentinel.dashboard.util.VersionUtils;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.web.bind.annotation.DeleteMapping;
  import org.springframework.web.bind.annotation.GetMapping;
  import org.springframework.web.bind.annotation.PathVariable;
  import org.springframework.web.bind.annotation.PostMapping;
  import org.springframework.web.bind.annotation.PutMapping;
  import org.springframework.web.bind.annotation.RequestBody;
  import org.springframework.web.bind.annotation.RequestMapping;
  import org.springframework.web.bind.annotation.RequestParam;
  import org.springframework.web.bind.annotation.RestController;
  
  /**
   * @author Eric Zhao
   * @since 0.2.1
   */
  @RestController
  @RequestMapping(value = "/paramFlow")
  public class ParamFlowRuleController {
  
      private final Logger logger = LoggerFactory.getLogger(ParamFlowRuleController.class);
  
      @Autowired
      private SentinelApiClient sentinelApiClient;
      @Autowired
      private AppManagement appManagement;
      @Autowired
      private RuleRepository<ParamFlowRuleEntity, Long> repository;
  
      private boolean checkIfSupported(String app, String ip, int port) {
          try {
              return Optional.ofNullable(appManagement.getDetailApp(app))
                  .flatMap(e -> e.getMachine(ip, port))
                  .flatMap(m -> VersionUtils.parseVersion(m.getVersion())
                      .map(v -> v.greaterOrEqual(version020)))
                  .orElse(true);
              // If error occurred or cannot retrieve machine info, return true.
          } catch (Exception ex) {
              return true;
          }
      }
  
      @GetMapping("/rules")
      @AuthAction(PrivilegeType.READ_RULE)
      public Result<List<ParamFlowRuleEntity>> apiQueryAllRulesForMachine(@RequestParam String app,
                                                                          @RequestParam String ip,
                                                                          @RequestParam Integer port) {
          if (StringUtil.isEmpty(app)) {
              return Result.ofFail(-1, "app cannot be null or empty");
          }
          if (StringUtil.isEmpty(ip)) {
              return Result.ofFail(-1, "ip cannot be null or empty");
          }
          if (port == null || port <= 0) {
              return Result.ofFail(-1, "Invalid parameter: port");
          }
          if (!checkIfSupported(app, ip, port)) {
              return unsupportedVersion();
          }
          try {
              return sentinelApiClient.fetchParamFlowRulesOfMachine(app, ip, port)
                  .thenApply(repository::saveAll)
                  .thenApply(Result::ofSuccess)
                  .get();
          } catch (ExecutionException ex) {
              logger.error("Error when querying parameter flow rules", ex.getCause());
              if (isNotSupported(ex.getCause())) {
                  return unsupportedVersion();
              } else {
                  return Result.ofThrowable(-1, ex.getCause());
              }
          } catch (Throwable throwable) {
              logger.error("Error when querying parameter flow rules", throwable);
              return Result.ofFail(-1, throwable.getMessage());
          }
      }
  
      private boolean isNotSupported(Throwable ex) {
          return ex instanceof CommandNotFoundException;
      }
  
      @PostMapping("/rule")
      @AuthAction(AuthService.PrivilegeType.WRITE_RULE)
      public Result<ParamFlowRuleEntity> apiAddParamFlowRule(@RequestBody ParamFlowRuleEntity entity) {
          Result<ParamFlowRuleEntity> checkResult = checkEntityInternal(entity);
          if (checkResult != null) {
              return checkResult;
          }
          if (!checkIfSupported(entity.getApp(), entity.getIp(), entity.getPort())) {
              return unsupportedVersion();
          }
          entity.setId(null);
          entity.getRule().setResource(entity.getResource().trim());
          Date date = new Date();
          entity.setGmtCreate(date);
          entity.setGmtModified(date);
          try {
              entity = repository.save(entity);
              publishRules(entity.getApp(), entity.getIp(), entity.getPort()).get();
              return Result.ofSuccess(entity);
          } catch (ExecutionException ex) {
              logger.error("Error when adding new parameter flow rules", ex.getCause());
              if (isNotSupported(ex.getCause())) {
                  return unsupportedVersion();
              } else {
                  return Result.ofThrowable(-1, ex.getCause());
              }
          } catch (Throwable throwable) {
              logger.error("Error when adding new parameter flow rules", throwable);
              return Result.ofFail(-1, throwable.getMessage());
          }
      }
  
      private <R> Result<R> checkEntityInternal(ParamFlowRuleEntity entity) {
          if (entity == null) {
              return Result.ofFail(-1, "bad rule body");
          }
          if (StringUtil.isBlank(entity.getApp())) {
              return Result.ofFail(-1, "app can't be null or empty");
          }
          if (StringUtil.isBlank(entity.getIp())) {
              return Result.ofFail(-1, "ip can't be null or empty");
          }
          if (entity.getPort() == null || entity.getPort() <= 0) {
              return Result.ofFail(-1, "port can't be null");
          }
          if (entity.getRule() == null) {
              return Result.ofFail(-1, "rule can't be null");
          }
          if (StringUtil.isBlank(entity.getResource())) {
              return Result.ofFail(-1, "resource name cannot be null or empty");
          }
          if (entity.getCount() < 0) {
              return Result.ofFail(-1, "count should be valid");
          }
          if (entity.getGrade() != RuleConstant.FLOW_GRADE_QPS) {
              return Result.ofFail(-1, "Unknown mode (blockGrade) for parameter flow control");
          }
          if (entity.getParamIdx() == null || entity.getParamIdx() < 0) {
              return Result.ofFail(-1, "paramIdx should be valid");
          }
          if (entity.getDurationInSec() <= 0) {
              return Result.ofFail(-1, "durationInSec should be valid");
          }
          if (entity.getControlBehavior() < 0) {
              return Result.ofFail(-1, "controlBehavior should be valid");
          }
          return null;
      }
  
      @PutMapping("/rule/{id}")
      @AuthAction(AuthService.PrivilegeType.WRITE_RULE)
      public Result<ParamFlowRuleEntity> apiUpdateParamFlowRule(@PathVariable("id") Long id,
                                                                @RequestBody ParamFlowRuleEntity entity) {
          if (id == null || id <= 0) {
              return Result.ofFail(-1, "Invalid id");
          }
          ParamFlowRuleEntity oldEntity = repository.findById(id);
          if (oldEntity == null) {
              return Result.ofFail(-1, "id " + id + " does not exist");
          }
  
          Result<ParamFlowRuleEntity> checkResult = checkEntityInternal(entity);
          if (checkResult != null) {
              return checkResult;
          }
          if (!checkIfSupported(entity.getApp(), entity.getIp(), entity.getPort())) {
              return unsupportedVersion();
          }
          entity.setId(id);
          Date date = new Date();
          entity.setGmtCreate(oldEntity.getGmtCreate());
          entity.setGmtModified(date);
          try {
              entity = repository.save(entity);
              publishRules(entity.getApp(), entity.getIp(), entity.getPort()).get();
              return Result.ofSuccess(entity);
          } catch (ExecutionException ex) {
              logger.error("Error when updating parameter flow rules, id=" + id, ex.getCause());
              if (isNotSupported(ex.getCause())) {
                  return unsupportedVersion();
              } else {
                  return Result.ofThrowable(-1, ex.getCause());
              }
          } catch (Throwable throwable) {
              logger.error("Error when updating parameter flow rules, id=" + id, throwable);
              return Result.ofFail(-1, throwable.getMessage());
          }
      }
  
      @DeleteMapping("/rule/{id}")
      @AuthAction(PrivilegeType.DELETE_RULE)
      public Result<Long> apiDeleteRule(@PathVariable("id") Long id) {
          if (id == null) {
              return Result.ofFail(-1, "id cannot be null");
          }
          ParamFlowRuleEntity oldEntity = repository.findById(id);
          if (oldEntity == null) {
              return Result.ofSuccess(null);
          }
  
          try {
              repository.delete(id);
              publishRules(oldEntity.getApp(), oldEntity.getIp(), oldEntity.getPort()).get();
              return Result.ofSuccess(id);
          } catch (ExecutionException ex) {
              logger.error("Error when deleting parameter flow rules", ex.getCause());
              if (isNotSupported(ex.getCause())) {
                  return unsupportedVersion();
              } else {
                  return Result.ofThrowable(-1, ex.getCause());
              }
          } catch (Throwable throwable) {
              logger.error("Error when deleting parameter flow rules", throwable);
              return Result.ofFail(-1, throwable.getMessage());
          }
      }
  
      private CompletableFuture<Void> publishRules(String app, String ip, Integer port) {
          List<ParamFlowRuleEntity> rules = repository.findAllByMachine(MachineInfo.of(app, ip, port));
          return sentinelApiClient.setParamFlowRuleOfMachine(app, ip, port, rules);
      }
  
      private <R> Result<R> unsupportedVersion() {
          return Result.ofFail(4041,
              "Sentinel client not supported for parameter flow control (unsupported version or dependency absent)");
      }
  
      private final SentinelVersion version020 = new SentinelVersion().setMinorVersion(2);
  }
  