[PM-5606] Add reactive generator service (#7446)

libs/common/src/tools/generator/abstractions/generator.service.abstraction.ts

@@ -0,0 +1,37 @@
+import { Observable } from "rxjs";
+
+import { PolicyEvaluator } from "./policy-evaluator.abstraction";
+
+/** Generates credentials used for user authentication
+ *  @typeParam Options the credential generation configuration
+ *  @typeParam Policy the policy enforced by the generator
+ */
+export abstract class GeneratorService<Options, Policy> {
+  /** An observable monitoring the options saved to disk.
+   *  The observable updates when the options are saved.
+   */
+  options$: Observable<Options>;
+
+  /** An observable monitoring the options used to enforce policy.
+   *  The observable updates when the policy changes.
+   */
+  policy$: Observable<PolicyEvaluator<Policy, Options>>;
+
+  /** Enforces the policy on the given options
+   * @param options the options to enforce the policy on
+   * @returns a new instance of the options with the policy enforced
+   */
+  enforcePolicy: (options: Options) => Promise<Options>;
+
+  /** Generates credentials
+   * @param options the options to generate credentials with
+   * @returns a promise that resolves with the generated credentials
+   */
+  generate: (options: Options) => Promise<string>;
+
+  /** Saves the given options to disk.
+   * @param options the options to save
+   * @returns a promise that resolves when the options are saved
+   */
+  saveOptions: (options: Options) => Promise<void>;
+}