added a RestRequest class for each http method

src/app/core/cache/builders/remote-data-build.service.ts

 import { Injectable } from '@angular/core';
 import { Observable } from 'rxjs/Observable';
+import { hasValue, isNotEmpty } from '../../../shared/empty.util';
 import { PaginatedList } from '../../data/paginated-list';
+import { RemoteData } from '../../data/remote-data';
 import { RemoteDataError } from '../../data/remote-data-error';
+import { GetRequest } from '../../data/request.models';
+import { RequestEntry } from '../../data/request.reducer';
+import { RequestService } from '../../data/request.service';
+import { GenericConstructor } from '../../shared/generic-constructor';
+import { NormalizedObjectFactory } from '../models/normalized-object-factory';
 
 import { CacheableObject } from '../object-cache.reducer';
 import { ObjectCacheService } from '../object-cache.service';
-import { RequestService } from '../../data/request.service';
-import { ResponseCacheService } from '../response-cache.service';
-import { RequestEntry } from '../../data/request.reducer';
-import { hasValue, isNotEmpty } from '../../../shared/empty.util';
+import { DSOSuccessResponse, ErrorResponse } from '../response-cache.models';
 import { ResponseCacheEntry } from '../response-cache.reducer';
-import { ErrorResponse, DSOSuccessResponse } from '../response-cache.models';
-import { RemoteData } from '../../data/remote-data';
-import { GenericConstructor } from '../../shared/generic-constructor';
+import { ResponseCacheService } from '../response-cache.service';
 import { getMapsTo, getRelationMetadata, getRelationships } from './build-decorators';
-import { NormalizedObjectFactory } from '../models/normalized-object-factory';
-import { RestRequest } from '../../data/request.models';
-import { PageInfo } from '../../shared/page-info.model';
 
 @Injectable()
 export class RemoteDataBuildService {
@@ -169,7 +168,7 @@ export class RemoteDataBuildService {
         const resourceConstructor = NormalizedObjectFactory.getConstructor(resourceType);
         if (Array.isArray(normalized[relationship])) {
           normalized[relationship].forEach((href: string) => {
-            this.requestService.configure(new RestRequest(this.requestService.generateRequestId(), href))
+            this.requestService.configure(new GetRequest(this.requestService.generateRequestId(), href))
           });
 
           const rdArr = [];
@@ -183,7 +182,7 @@ export class RemoteDataBuildService {
             links[relationship] = rdArr[0];
           }
         } else {
-          this.requestService.configure(new RestRequest(this.requestService.generateRequestId(), normalized[relationship]));
+          this.requestService.configure(new GetRequest(this.requestService.generateRequestId(), normalized[relationship]));
 
           // The rest API can return a single URL to represent a list of resources (e.g. /items/:id/bitstreams)
           // in that case only 1 href will be stored in the normalized obj (so the isArray above fails),

src/app/core/data/data.service.ts

@@ -6,19 +6,12 @@ import { RemoteDataBuildService } from '../cache/builders/remote-data-build.serv
 import { CacheableObject } from '../cache/object-cache.reducer';
 import { ResponseCacheService } from '../cache/response-cache.service';
 import { CoreState } from '../core.reducers';
-import { DSpaceObject } from '../shared/dspace-object.model';
 import { GenericConstructor } from '../shared/generic-constructor';
 import { HALEndpointService } from '../shared/hal-endpoint.service';
 import { URLCombiner } from '../url-combiner/url-combiner';
 import { PaginatedList } from './paginated-list';
 import { RemoteData } from './remote-data';
-import {
-  FindAllOptions,
-  FindAllRequest,
-  FindByIDRequest,
-  RestRequest,
-  RestRequestMethod
-} from './request.models';
+import { FindAllOptions, FindAllRequest, FindByIDRequest, GetRequest } from './request.models';
 import { RequestService } from './request.service';
 
 export abstract class DataService<TNormalized extends CacheableObject, TDomain> extends HALEndpointService {
@@ -106,7 +99,7 @@ export abstract class DataService<TNormalized extends CacheableObject, TDomain>
   }
 
   findByHref(href: string): Observable<RemoteData<TDomain>> {
-    this.requestService.configure(new RestRequest(this.requestService.generateRequestId(), href));
+    this.requestService.configure(new GetRequest(this.requestService.generateRequestId(), href));
     return this.rdbService.buildSingle<TNormalized, TDomain>(href, this.normalizedResourceType);
   }
 

src/app/core/data/request.models.ts

@@ -22,14 +22,14 @@ import { ConfigResponseParsingService } from './config-response-parsing.service'
 export enum RestRequestMethod {
   Get = 'GET',
   Post = 'POST',
-  // Put = 'PUT',
-  // Delete = 'DELETE',
-  // Options = 'OPTIONS',
-  // Head = 'HEAD',
-  // Patch = 'PATCH'
+  Put = 'PUT',
+  Delete = 'DELETE',
+  Options = 'OPTIONS',
+  Head = 'HEAD',
+  Patch = 'PATCH'
 }
 
-export class RestRequest {
+export abstract class RestRequest {
   constructor(
     public uuid: string,
     public href: string,
@@ -43,6 +43,76 @@ export class RestRequest {
   }
 }
 
+export class GetRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Get, body)
+  }
+}
+
+export class PostRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Post, body)
+  }
+}
+
+export class PutRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Put, body)
+  }
+}
+
+export class DeleteRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Delete, body)
+  }
+}
+
+export class OptionsRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Options, body)
+  }
+}
+
+export class HeadRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Head, body)
+  }
+}
+
+export class PatchRequest extends RestRequest {
+  constructor(
+    public uuid: string,
+    public href: string,
+    public body?: any
+  )  {
+    super(uuid, href, RestRequestMethod.Patch, body)
+  }
+}
+
 export class FindByIDRequest extends RestRequest {
   constructor(
     uuid: string,

src/app/core/data/request.reducer.spec.ts

@@ -4,7 +4,7 @@ import { requestReducer, RequestState } from './request.reducer';
 import {
   RequestCompleteAction, RequestConfigureAction, RequestExecuteAction
 } from './request.actions';
-import { RestRequest } from './request.models';
+import { GetRequest, RestRequest } from './request.models';
 
 class NullAction extends RequestCompleteAction {
   type = null;
@@ -22,7 +22,7 @@ describe('requestReducer', () => {
   const link2 = 'https://dspace7.4science.it/dspace-spring-rest/api/core/items/1911e8a4-6939-490c-b58b-a5d70f8d91fb';
   const testState: RequestState = {
     [id1]: {
-      request: new RestRequest(id1, link1),
+      request: new GetRequest(id1, link1),
       requestPending: false,
       responsePending: false,
       completed: false
@@ -46,7 +46,7 @@ describe('requestReducer', () => {
 
   it('should add the new RestRequest and set \'requestPending\' to true, \'responsePending\' to false and \'completed\' to false for the given RestRequest in the state, in response to a CONFIGURE action', () => {
     const state = testState;
-    const request = new RestRequest(id2, link2);
+    const request = new GetRequest(id2, link2);
 
     const action = new RequestConfigureAction(request);
     const newState = requestReducer(state, action);