feat(aio): implement GithubTeams

aio/aio-builds-setup/dockerbuild/scripts-js/lib/common/github-teams.ts

@@ -0,0 +1,45 @@
+// Imports
+import {assertNotMissingOrEmpty} from '../common/utils';
+import {GithubApi} from './github-api';
+
+// Interfaces - Types
+interface Team {
+  id: number;
+  slug: string;
+}
+
+interface TeamMembership {
+  state: string;
+}
+
+// Classes
+export class GithubTeams extends GithubApi {
+  // Constructor
+  constructor(githubToken: string, protected organization: string) {
+    super(githubToken);
+    assertNotMissingOrEmpty('organization', organization);
+  }
+
+  // Methods - Public
+  public fetchAll(): Promise<Team[]> {
+    return this.getPaginated<Team>(`/orgs/${this.organization}/teams`);
+  }
+
+  public isMemberById(username: string, teamIds: number[]): Promise<boolean> {
+    const getMembership = (teamId: number) =>
+      this.get<TeamMembership>(`/teams/${teamId}/memberships/${username}`).
+        then(membership => membership.state === 'active').
+        catch(() => false);
+    const reduceFn = (promise: Promise<boolean>, teamId: number) =>
+      promise.then(isMember => isMember || getMembership(teamId));
+
+    return teamIds.reduce(reduceFn, Promise.resolve(false));
+  }
+
+  public isMemberBySlug(username: string, teamSlugs: string[]): Promise<boolean> {
+    return this.fetchAll().
+      then(teams => teams.filter(team => teamSlugs.includes(team.slug)).map(team => team.id)).
+      then(teamIds => this.isMemberById(username, teamIds)).
+      catch(() => false);
+  }
+}