[CST-4878] Finished working on embargo add part of form and unit testing

src/app/submission/sections/accesses/section-accesses.service.ts

@@ -0,0 +1,44 @@
+import { Injectable } from '@angular/core';
+
+import { Observable, of } from 'rxjs';
+import { distinctUntilChanged, filter, map } from 'rxjs/operators';
+import { Store } from '@ngrx/store';
+
+import { SubmissionState } from '../../submission.reducers';
+import { isUndefined } from 'util';
+import { submissionSectionFromIdSelector, submissionSectionDataFromIdSelector } from 'src/app/submission/selectors';
+
+
+/**
+ * A service that provides methods to handle submission's bitstream state.
+ */
+@Injectable()
+export class SectionAccessesService {
+
+  /**
+   * Initialize service variables
+   *
+   * @param {Store<SubmissionState>} store
+   */
+  constructor(private store: Store<SubmissionState>) { }
+
+
+  /**
+   * Return bitstream's metadata
+   *
+   * @param submissionId
+   *    The submission id
+   * @param sectionId
+   *    The section id
+   * @param fileUUID
+   *    The bitstream UUID
+   * @returns {Observable}
+   *    Emits bitstream's metadata
+   */
+  public getAccessesData(submissionId: string, sectionId: string): Observable<any> {
+
+    return this.store.select(submissionSectionDataFromIdSelector(submissionId, sectionId)).pipe(
+      filter((state) => !isUndefined(state)),
+      distinctUntilChanged());
+  }
+}