gerrit.onap Code Review - ccsdk/oran.git/blob

   1 /*-
   2  * ========================LICENSE_START=================================
   3  * ONAP : ccsdk oran
   4  * ======================================================================
   5  * Copyright (C) 2019-2020 Nordix Foundation. All rights reserved.
   6  * ======================================================================
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  * ========================LICENSE_END===================================
  19  */
  20
  21 package org.onap.ccsdk.oran.a1policymanagementservice.controllers.v2;
  22
  23 import com.google.gson.Gson;
  24 import com.google.gson.GsonBuilder;
  25
  26 import io.swagger.v3.oas.annotations.Operation;
  27 import io.swagger.v3.oas.annotations.Parameter;
  28 import io.swagger.v3.oas.annotations.media.Content;
  29 import io.swagger.v3.oas.annotations.media.Schema;
  30 import io.swagger.v3.oas.annotations.responses.ApiResponse;
  31 import io.swagger.v3.oas.annotations.responses.ApiResponses;
  32 import io.swagger.v3.oas.annotations.tags.Tag;
  33
  34 import java.lang.invoke.MethodHandles;
  35 import java.time.Instant;
  36 import java.util.ArrayList;
  37 import java.util.Collection;
  38 import java.util.List;
  39
  40 import lombok.Getter;
  41
  42 import org.onap.ccsdk.oran.a1policymanagementservice.clients.A1ClientFactory;
  43 import org.onap.ccsdk.oran.a1policymanagementservice.controllers.VoidResponse;
  44 import org.onap.ccsdk.oran.a1policymanagementservice.exceptions.EntityNotFoundException;
  45 import org.onap.ccsdk.oran.a1policymanagementservice.exceptions.ServiceException;
  46 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Lock;
  47 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Lock.LockType;
  48 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Policies;
  49 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Policy;
  50 import org.onap.ccsdk.oran.a1policymanagementservice.repository.PolicyType;
  51 import org.onap.ccsdk.oran.a1policymanagementservice.repository.PolicyTypes;
  52 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Ric;
  53 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Rics;
  54 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Service;
  55 import org.onap.ccsdk.oran.a1policymanagementservice.repository.Services;
  56 import org.slf4j.Logger;
  57 import org.slf4j.LoggerFactory;
  58 import org.springframework.beans.factory.annotation.Autowired;
  59 import org.springframework.http.HttpStatus;
  60 import org.springframework.http.MediaType;
  61 import org.springframework.http.ResponseEntity;
  62 import org.springframework.web.bind.annotation.DeleteMapping;
  63 import org.springframework.web.bind.annotation.GetMapping;
  64 import org.springframework.web.bind.annotation.PathVariable;
  65 import org.springframework.web.bind.annotation.PutMapping;
  66 import org.springframework.web.bind.annotation.RequestBody;
  67 import org.springframework.web.bind.annotation.RequestParam;
  68 import org.springframework.web.bind.annotation.RestController;
  69 import org.springframework.web.reactive.function.client.WebClientResponseException;
  70 import reactor.core.publisher.Mono;
  71
  72 @RestController("PolicyControllerV2")
  73 @Tag(//
  74         name = PolicyController.API_NAME, //
  75         description = PolicyController.API_DESCRIPTION //
  76 )
  77 public class PolicyController {
  78
  79     public static final String API_NAME = "A1 Policy Management";
  80     public static final String API_DESCRIPTION = "";
  81
  82     public static class RejectionException extends Exception {
  83         private static final long serialVersionUID = 1L;
  84
  85         @Getter
  86         private final HttpStatus status;
  87
  88         public RejectionException(String message, HttpStatus status) {
  89             super(message);
  90             this.status = status;
  91         }
  92     }
  93
  94     @Autowired
  95     private Rics rics;
  96     @Autowired
  97     private PolicyTypes policyTypes;
  98     @Autowired
  99     private Policies policies;
 100     @Autowired
 101     private A1ClientFactory a1ClientFactory;
 102     @Autowired
 103     private Services services;
 104
 105     private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
 106     private static Gson gson = new GsonBuilder() //
 107             .create(); //
 108
 109     @GetMapping(path = Consts.V2_API_ROOT + "/policy-types/{policytype_id:.+}") //
 110     @Operation(summary = "Returns a policy type definition") //
 111     @ApiResponses(value = { //
 112             @ApiResponse(responseCode = "200", //
 113                     description = "Policy type", //
 114                     content = @Content(schema = @Schema(implementation = PolicyTypeInfo.class))), //
 115             @ApiResponse(responseCode = "404", //
 116                     description = "Policy type is not found", //
 117                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class)))//
 118     })
 119     public ResponseEntity<Object> getPolicyType( //
 120             @PathVariable("policytype_id") String policyTypeId) throws EntityNotFoundException {
 121         PolicyType type = policyTypes.getType(policyTypeId);
 122         PolicyTypeInfo info = new PolicyTypeInfo(type.getSchema());
 123         return new ResponseEntity<>(gson.toJson(info), HttpStatus.OK);
 124     }
 125
 126     @GetMapping(path = Consts.V2_API_ROOT + "/policy-types", produces = MediaType.APPLICATION_JSON_VALUE)
 127     @Operation(summary = "Query policy type identities")
 128     @ApiResponses(value = { //
 129             @ApiResponse(responseCode = "200", //
 130                     description = "Policy type IDs", //
 131                     content = @Content(schema = @Schema(implementation = PolicyTypeIdList.class))), //
 132             @ApiResponse(responseCode = "404", //
 133                     description = "Near-RT RIC is not found", //
 134                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 135     })
 136     public ResponseEntity<Object> getPolicyTypes( //
 137             @Parameter(name = Consts.RIC_ID_PARAM, required = false, //
 138                     description = "Select types for the given Near-RT RIC identity.") //
 139             @RequestParam(name = Consts.RIC_ID_PARAM, required = false) String ricId,
 140
 141             @Parameter(name = Consts.TYPE_NAME_PARAM, required = false, //
 142                     description = "Select types with the given type name (type identity has the format <typename_version>)") //
 143             @RequestParam(name = Consts.TYPE_NAME_PARAM, required = false) String typeName,
 144
 145             @Parameter(name = Consts.COMPATIBLE_WITH_VERSION_PARAM, required = false, //
 146                     description = "Select types that are compatible with the given version. This parameter is only applicable in conjunction with "
 147                             + Consts.TYPE_NAME_PARAM
 148                             + ". As an example version 1.9.1 is compatible with 1.0.0 but not the other way around."
 149                             + " Matching types will be returned sorted in ascending order.") //
 150             @RequestParam(name = Consts.COMPATIBLE_WITH_VERSION_PARAM, required = false) String compatibleWithVersion
 151
 152     ) throws ServiceException {
 153
 154         if (compatibleWithVersion != null && typeName == null) {
 155             throw new ServiceException("Parameter " + Consts.COMPATIBLE_WITH_VERSION_PARAM + " can only be used when "
 156                     + Consts.TYPE_NAME_PARAM + " is given", HttpStatus.BAD_REQUEST);
 157         }
 158
 159         Collection<PolicyType> types =
 160                 ricId != null ? rics.getRic(ricId).getSupportedPolicyTypes() : this.policyTypes.getAll();
 161
 162         types = PolicyTypes.filterTypes(types, typeName, compatibleWithVersion);
 163         return new ResponseEntity<>(toPolicyTypeIdsJson(types), HttpStatus.OK);
 164     }
 165
 166     @GetMapping(path = Consts.V2_API_ROOT + "/policies/{policy_id:.+}", produces = MediaType.APPLICATION_JSON_VALUE)
 167     @Operation(summary = "Returns a policy") //
 168     @ApiResponses(value = { //
 169             @ApiResponse(responseCode = "200", //
 170                     description = "Policy found", //
 171                     content = @Content(schema = @Schema(implementation = PolicyInfo.class))), //
 172             @ApiResponse(responseCode = "404", //
 173                     description = "Policy is not found", //
 174                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 175     })
 176     public ResponseEntity<Object> getPolicy( //
 177             @PathVariable(name = Consts.POLICY_ID_PARAM, required = true) String id) throws EntityNotFoundException {
 178         Policy p = policies.getPolicy(id);
 179         return new ResponseEntity<>(gson.toJson(toPolicyInfo(p)), HttpStatus.OK);
 180     }
 181
 182     @DeleteMapping(Consts.V2_API_ROOT + "/policies/{policy_id:.+}")
 183     @Operation(summary = "Delete a policy")
 184     @ApiResponses(value = { //
 185             @ApiResponse(responseCode = "200", //
 186                     description = "Not used", //
 187                     content = @Content(schema = @Schema(implementation = VoidResponse.class))), //
 188             @ApiResponse(responseCode = "204", //
 189                     description = "Policy deleted", //
 190                     content = @Content(schema = @Schema(implementation = VoidResponse.class))), //
 191             @ApiResponse(responseCode = "404", //
 192                     description = "Policy is not found", //
 193                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))), //
 194             @ApiResponse(responseCode = "423", //
 195                     description = "Near-RT RIC is not operational", //
 196                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 197     })
 198     public Mono<ResponseEntity<Object>> deletePolicy( //
 199             @PathVariable(Consts.POLICY_ID_PARAM) String policyId) throws EntityNotFoundException {
 200         Policy policy = policies.getPolicy(policyId);
 201         keepServiceAlive(policy.getOwnerServiceId());
 202
 203         return policy.getRic().getLock().lock(LockType.SHARED, "deletePolicy") //
 204                 .flatMap(grant -> deletePolicy(grant, policy));
 205     }
 206
 207     Mono<ResponseEntity<Object>> deletePolicy(Lock.Grant grant, Policy policy) {
 208         return assertRicStateIdle(policy.getRic()) //
 209                 .flatMap(notUsed -> a1ClientFactory.createA1Client(policy.getRic())) //
 210                 .doOnNext(notUsed -> policies.remove(policy)) //
 211                 .doFinally(x -> grant.unlockBlocking()) //
 212                 .flatMap(client -> client.deletePolicy(policy)) //
 213                 .map(notUsed -> new ResponseEntity<>(HttpStatus.NO_CONTENT)) //
 214                 .onErrorResume(this::handleException);
 215     }
 216
 217     @PutMapping(path = Consts.V2_API_ROOT + "/policies", produces = MediaType.APPLICATION_JSON_VALUE)
 218     @Operation(summary = "Create or update a policy")
 219     @ApiResponses(value = { //
 220             @ApiResponse(responseCode = "201", //
 221                     description = "Policy created", //
 222                     content = @Content(schema = @Schema(implementation = VoidResponse.class))), //
 223             @ApiResponse(responseCode = "200", //
 224                     description = "Policy updated", //
 225                     content = @Content(schema = @Schema(implementation = VoidResponse.class))), //
 226             @ApiResponse(responseCode = "423", //
 227                     description = "Near-RT RIC is not operational", //
 228                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))), //
 229             @ApiResponse(responseCode = "404", //
 230                     description = "Near-RT RIC or policy type is not found", //
 231                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 232     })
 233     public Mono<ResponseEntity<Object>> putPolicy(@RequestBody PolicyInfo policyInfo) throws EntityNotFoundException {
 234
 235         if (!policyInfo.validate()) {
 236             return ErrorResponse.createMono("Missing required parameter in body", HttpStatus.BAD_REQUEST);
 237         }
 238         String jsonString = gson.toJson(policyInfo.policyData);
 239         Ric ric = rics.get(policyInfo.ricId);
 240         PolicyType type = policyTypes.get(policyInfo.policyTypeId);
 241         keepServiceAlive(policyInfo.serviceId);
 242         if (ric == null || type == null) {
 243             throw new EntityNotFoundException("Near-RT RIC or policy type not found");
 244         }
 245         Policy policy = Policy.builder() //
 246                 .id(policyInfo.policyId) //
 247                 .json(jsonString) //
 248                 .type(type) //
 249                 .ric(ric) //
 250                 .ownerServiceId(policyInfo.serviceId) //
 251                 .lastModified(Instant.now()) //
 252                 .isTransient(policyInfo.isTransient) //
 253                 .statusNotificationUri(policyInfo.statusNotificationUri == null ? "" : policyInfo.statusNotificationUri) //
 254                 .build();
 255
 256         return ric.getLock().lock(LockType.SHARED, "putPolicy") //
 257                 .flatMap(grant -> putPolicy(grant, policy));
 258     }
 259
 260     private Mono<ResponseEntity<Object>> putPolicy(Lock.Grant grant, Policy policy) {
 261         final boolean isCreate = this.policies.get(policy.getId()) == null;
 262         final Ric ric = policy.getRic();
 263
 264         return assertRicStateIdle(ric) //
 265                 .flatMap(notUsed -> checkSupportedType(ric, policy.getType())) //
 266                 .flatMap(notUsed -> validateModifiedPolicy(policy)) //
 267                 .flatMap(notUsed -> a1ClientFactory.createA1Client(ric)) //
 268                 .flatMap(client -> client.putPolicy(policy)) //
 269                 .doOnNext(notUsed -> policies.put(policy)) //
 270                 .doFinally(x -> grant.unlockBlocking()) //
 271                 .flatMap(notUsed -> Mono.just(new ResponseEntity<>(isCreate ? HttpStatus.CREATED : HttpStatus.OK))) //
 272                 .onErrorResume(this::handleException);
 273
 274     }
 275
 276     private Mono<ResponseEntity<Object>> handleException(Throwable throwable) {
 277         if (throwable instanceof WebClientResponseException) {
 278             WebClientResponseException e = (WebClientResponseException) throwable;
 279             return ErrorResponse.createMono(e.getResponseBodyAsString(), e.getStatusCode());
 280         } else if (throwable instanceof RejectionException) {
 281             RejectionException e = (RejectionException) throwable;
 282             return ErrorResponse.createMono(e.getMessage(), e.getStatus());
 283         } else {
 284             return ErrorResponse.createMono(throwable.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
 285         }
 286     }
 287
 288     private Mono<Object> validateModifiedPolicy(Policy policy) {
 289         // Check that ric is not updated
 290         Policy current = this.policies.get(policy.getId());
 291         if (current != null && !current.getRic().id().equals(policy.getRic().id())) {
 292             RejectionException e = new RejectionException("Policy cannot change RIC, policyId: " + current.getId() + //
 293                     ", RIC ID: " + current.getRic().id() + //
 294                     ", new ID: " + policy.getRic().id(), HttpStatus.CONFLICT);
 295             logger.debug("Request rejected, {}", e.getMessage());
 296             return Mono.error(e);
 297         }
 298         return Mono.just("{}");
 299     }
 300
 301     private Mono<Object> checkSupportedType(Ric ric, PolicyType type) {
 302         if (!ric.isSupportingType(type.getId())) {
 303             logger.debug("Request rejected, type not supported, RIC: {}", ric);
 304             RejectionException e = new RejectionException(
 305                     "Type: " + type.getId() + " not supported by RIC: " + ric.id(), HttpStatus.NOT_FOUND);
 306             return Mono.error(e);
 307         }
 308         return Mono.just("{}");
 309     }
 310
 311     private Mono<Object> assertRicStateIdle(Ric ric) {
 312         if (ric.getState() == Ric.RicState.AVAILABLE) {
 313             return Mono.just("{}");
 314         } else {
 315             logger.debug("Request rejected Near-RT RIC not IDLE, ric: {}", ric);
 316             RejectionException e = new RejectionException(
 317                     "Near-RT RIC: is not operational, id: " + ric.id() + ", state: " + ric.getState(),
 318                     HttpStatus.LOCKED);
 319             return Mono.error(e);
 320         }
 321     }
 322
 323     static final String GET_POLICIES_QUERY_DETAILS =
 324             "Returns a list of A1 policies matching given search criteria. <br>" //
 325                     + "If several query parameters are defined, the policies matching all conditions are returned.";
 326
 327     @GetMapping(path = Consts.V2_API_ROOT + "/policy-instances", produces = MediaType.APPLICATION_JSON_VALUE)
 328     @Operation(summary = "Query for A1 policy instances", description = GET_POLICIES_QUERY_DETAILS)
 329     @ApiResponses(value = { //
 330             @ApiResponse(responseCode = "200", //
 331                     description = "Policies", //
 332                     content = @Content(schema = @Schema(implementation = PolicyInfoList.class))), //
 333             @ApiResponse(responseCode = "404", //
 334                     description = "Near-RT RIC, policy type or service not found", //
 335                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 336     })
 337     public ResponseEntity<Object> getPolicyInstances( //
 338             @Parameter(name = Consts.POLICY_TYPE_ID_PARAM, required = false,
 339                     description = "Select policies with a given type identity.") //
 340             @RequestParam(name = Consts.POLICY_TYPE_ID_PARAM, required = false) String typeId, //
 341             @Parameter(name = Consts.RIC_ID_PARAM, required = false,
 342                     description = "Select policies for a given Near-RT RIC identity.") //
 343             @RequestParam(name = Consts.RIC_ID_PARAM, required = false) String ric, //
 344             @Parameter(name = Consts.SERVICE_ID_PARAM, required = false,
 345                     description = "Select policies owned by a given service.") //
 346             @RequestParam(name = Consts.SERVICE_ID_PARAM, required = false) String service,
 347             @Parameter(name = Consts.TYPE_NAME_PARAM, required = false, //
 348                     description = "Select policies of a given type name (type identity has the format <typename_version>)") //
 349             @RequestParam(name = Consts.TYPE_NAME_PARAM, required = false) String typeName)
 350             throws EntityNotFoundException //
 351     {
 352         if ((typeId != null && this.policyTypes.get(typeId) == null)) {
 353             throw new EntityNotFoundException("Policy type identity not found");
 354         }
 355         if ((ric != null && this.rics.get(ric) == null)) {
 356             throw new EntityNotFoundException("Near-RT RIC not found");
 357         }
 358
 359         String filteredPolicies = policiesToJson(policies.filterPolicies(typeId, ric, service, typeName));
 360         return new ResponseEntity<>(filteredPolicies, HttpStatus.OK);
 361     }
 362
 363     @GetMapping(path = Consts.V2_API_ROOT + "/policies", produces = MediaType.APPLICATION_JSON_VALUE) //
 364     @Operation(summary = "Query policy identities", description = GET_POLICIES_QUERY_DETAILS) //
 365     @ApiResponses(value = { //
 366             @ApiResponse(responseCode = "200", //
 367                     description = "Policy identities", //
 368                     content = @Content(schema = @Schema(implementation = PolicyIdList.class))), //
 369             @ApiResponse(responseCode = "404", //
 370                     description = "Near-RT RIC or type not found", //
 371                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 372     })
 373     public ResponseEntity<Object> getPolicyIds( //
 374             @Parameter(name = Consts.POLICY_TYPE_ID_PARAM, required = false, //
 375                     description = "Select policies of a given policy type identity.") //
 376             @RequestParam(name = Consts.POLICY_TYPE_ID_PARAM, required = false) String policyTypeId, //
 377             @Parameter(name = Consts.RIC_ID_PARAM, required = false, //
 378                     description = "Select policies of a given Near-RT RIC identity.") //
 379             @RequestParam(name = Consts.RIC_ID_PARAM, required = false) String ricId, //
 380             @Parameter(name = Consts.SERVICE_ID_PARAM, required = false, //
 381                     description = "Select policies owned by a given service.") //
 382             @RequestParam(name = Consts.SERVICE_ID_PARAM, required = false) String serviceId,
 383             @Parameter(name = Consts.TYPE_NAME_PARAM, required = false, //
 384                     description = "Select policies of types with the given type name (type identity has the format <typename_version>)") //
 385             @RequestParam(name = Consts.TYPE_NAME_PARAM, required = false) String typeName)
 386             throws EntityNotFoundException //
 387     {
 388         if ((policyTypeId != null && this.policyTypes.get(policyTypeId) == null)) {
 389             throw new EntityNotFoundException("Policy type not found");
 390         }
 391         if ((ricId != null && this.rics.get(ricId) == null)) {
 392             throw new EntityNotFoundException("Near-RT RIC not found");
 393         }
 394
 395         String policyIdsJson = toPolicyIdsJson(policies.filterPolicies(policyTypeId, ricId, serviceId, typeName));
 396         return new ResponseEntity<>(policyIdsJson, HttpStatus.OK);
 397     }
 398
 399     @GetMapping(path = Consts.V2_API_ROOT + "/policies/{policy_id}/status", produces = MediaType.APPLICATION_JSON_VALUE)
 400     @Operation(summary = "Returns a policy status") //
 401     @ApiResponses(value = { //
 402             @ApiResponse(responseCode = "200", //
 403                     description = "Policy status", //
 404                     content = @Content(schema = @Schema(implementation = PolicyStatusInfo.class))), //
 405             @ApiResponse(responseCode = "404", //
 406                     description = "Policy is not found", //
 407                     content = @Content(schema = @Schema(implementation = ErrorResponse.ErrorInfo.class))) //
 408     })
 409     public Mono<ResponseEntity<Object>> getPolicyStatus( //
 410             @PathVariable(Consts.POLICY_ID_PARAM) String policyId) throws EntityNotFoundException {
 411         Policy policy = policies.getPolicy(policyId);
 412
 413         return a1ClientFactory.createA1Client(policy.getRic()) //
 414                 .flatMap(client -> client.getPolicyStatus(policy).onErrorResume(e -> Mono.just("{}"))) //
 415                 .flatMap(status -> createPolicyStatus(policy, status)) //
 416                 .onErrorResume(this::handleException);
 417
 418     }
 419
 420     private Mono<ResponseEntity<Object>> createPolicyStatus(Policy policy, String statusFromNearRic) {
 421         PolicyStatusInfo info = new PolicyStatusInfo(policy.getLastModified(), fromJson(statusFromNearRic));
 422         String str = gson.toJson(info);
 423         return Mono.just(new ResponseEntity<>(str, HttpStatus.OK));
 424     }
 425
 426     private void keepServiceAlive(String name) {
 427         Service s = this.services.get(name);
 428         if (s != null) {
 429             s.keepAlive();
 430         }
 431     }
 432
 433     private PolicyInfo toPolicyInfo(Policy p) {
 434         PolicyInfo policyInfo = new PolicyInfo();
 435         policyInfo.policyId = p.getId();
 436         policyInfo.policyData = fromJson(p.getJson());
 437         policyInfo.ricId = p.getRic().id();
 438         policyInfo.policyTypeId = p.getType().getId();
 439         policyInfo.serviceId = p.getOwnerServiceId();
 440         policyInfo.isTransient = p.isTransient();
 441         if (!p.getStatusNotificationUri().isEmpty()) {
 442             policyInfo.statusNotificationUri = p.getStatusNotificationUri();
 443         }
 444         if (!policyInfo.validate()) {
 445             logger.error("BUG, all mandatory fields must be set");
 446         }
 447
 448         return policyInfo;
 449     }
 450
 451     private String policiesToJson(Collection<Policy> policies) {
 452         List<PolicyInfo> v = new ArrayList<>(policies.size());
 453         for (Policy p : policies) {
 454             v.add(toPolicyInfo(p));
 455         }
 456         PolicyInfoList list = new PolicyInfoList(v);
 457         return gson.toJson(list);
 458     }
 459
 460     private Object fromJson(String jsonStr) {
 461         return gson.fromJson(jsonStr, Object.class);
 462     }
 463
 464     private String toPolicyTypeIdsJson(Collection<PolicyType> types) {
 465         List<String> v = new ArrayList<>(types.size());
 466         for (PolicyType t : types) {
 467             v.add(t.getId());
 468         }
 469         PolicyTypeIdList ids = new PolicyTypeIdList(v);
 470         return gson.toJson(ids);
 471     }
 472
 473     private String toPolicyIdsJson(Collection<Policy> policies) {
 474         List<String> v = new ArrayList<>(policies.size());
 475         for (Policy p : policies) {
 476             v.add(p.getId());
 477         }
 478         return gson.toJson(new PolicyIdList(v));
 479     }
 480
 481 }