[PM-5972] add subaddress generator strategy (#7897)

libs/common/src/tools/generator/key-definition.spec.ts

@@ -1,6 +1,7 @@
 import {
   ENCRYPTED_HISTORY,
   EFF_USERNAME_SETTINGS,
+  SUBADDRESS_SETTINGS,
   PASSPHRASE_SETTINGS,
   PASSWORD_SETTINGS,
 } from "./key-definitions";
@@ -30,6 +31,14 @@ describe("Key definitions", () => {
     });
   });
 
+  describe("SUBADDRESS_SETTINGS", () => {
+    it("should pass through deserialization", () => {
+      const value = {};
+      const result = SUBADDRESS_SETTINGS.deserializer(value);
+      expect(result).toBe(value);
+    });
+  });
+
   describe("ENCRYPTED_HISTORY", () => {
     it("should pass through deserialization", () => {
       const value = {};

libs/common/src/tools/generator/key-definitions.ts

@@ -4,6 +4,7 @@ import { PassphraseGenerationOptions } from "./passphrase/passphrase-generation-
 import { GeneratedPasswordHistory } from "./password/generated-password-history";
 import { PasswordGenerationOptions } from "./password/password-generation-options";
 import { EffUsernameGenerationOptions } from "./username/eff-username-generator-options";
+import { SubaddressGenerationOptions } from "./username/subaddress-generator-options";
 
 /** plaintext password generation options */
 export const PASSWORD_SETTINGS = new KeyDefinition<PasswordGenerationOptions>(
@@ -32,6 +33,15 @@ export const EFF_USERNAME_SETTINGS = new KeyDefinition<EffUsernameGenerationOpti
   },
 );
 
+/** email subaddress generation options */
+export const SUBADDRESS_SETTINGS = new KeyDefinition<SubaddressGenerationOptions>(
+  GENERATOR_DISK,
+  "subaddressGeneratorSettings",
+  {
+    deserializer: (value) => value,
+  },
+);
+
 /** encrypted password generation history */
 export const ENCRYPTED_HISTORY = new KeyDefinition<GeneratedPasswordHistory>(
   GENERATOR_DISK,

libs/common/src/tools/generator/username/index.ts

@@ -1,4 +1,5 @@
 export { EffUsernameGeneratorStrategy } from "./eff-username-generator-strategy";
+export { SubaddressGeneratorStrategy } from "./subaddress-generator-strategy";
 export { UsernameGeneratorOptions } from "./username-generation-options";
 export { UsernameGenerationServiceAbstraction } from "./username-generation.service.abstraction";
 export { UsernameGenerationService } from "./username-generation.service";

libs/common/src/tools/generator/username/subaddress-generator-options.ts

@@ -0,0 +1,10 @@
+/** Settings supported when generating an email subaddress */
+export type SubaddressGenerationOptions = {
+  type?: "random" | "website-name";
+  email?: string;
+};
+
+/** The default options for email subaddress generation. */
+export const DefaultSubaddressOptions: Partial<SubaddressGenerationOptions> = Object.freeze({
+  type: "random",
+});

libs/common/src/tools/generator/username/subaddress-generator-strategy.spec.ts

@@ -0,0 +1,83 @@
+import { mock } from "jest-mock-extended";
+
+import { PolicyType } from "../../../admin-console/enums";
+// FIXME: use index.ts imports once policy abstractions and models
+// implement ADR-0002
+import { Policy } from "../../../admin-console/models/domain/policy";
+import { DefaultPolicyEvaluator } from "../default-policy-evaluator";
+import { SUBADDRESS_SETTINGS } from "../key-definitions";
+
+import { SubaddressGeneratorStrategy, UsernameGenerationServiceAbstraction } from ".";
+
+describe("Email subaddress list generation strategy", () => {
+  describe("evaluator()", () => {
+    it("should throw if the policy type is incorrect", () => {
+      const strategy = new SubaddressGeneratorStrategy(null);
+      const policy = mock<Policy>({
+        type: PolicyType.DisableSend,
+      });
+
+      expect(() => strategy.evaluator(policy)).toThrow(new RegExp("Mismatched policy type\\. .+"));
+    });
+
+    it("should map to the policy evaluator", () => {
+      const strategy = new SubaddressGeneratorStrategy(null);
+      const policy = mock<Policy>({
+        type: PolicyType.PasswordGenerator,
+        data: {
+          minLength: 10,
+        },
+      });
+
+      const evaluator = strategy.evaluator(policy);
+
+      expect(evaluator).toBeInstanceOf(DefaultPolicyEvaluator);
+      expect(evaluator.policy).toMatchObject({});
+    });
+  });
+
+  describe("disk", () => {
+    it("should use password settings key", () => {
+      const legacy = mock<UsernameGenerationServiceAbstraction>();
+      const strategy = new SubaddressGeneratorStrategy(legacy);
+
+      expect(strategy.disk).toBe(SUBADDRESS_SETTINGS);
+    });
+  });
+
+  describe("cache_ms", () => {
+    it("should be a positive non-zero number", () => {
+      const legacy = mock<UsernameGenerationServiceAbstraction>();
+      const strategy = new SubaddressGeneratorStrategy(legacy);
+
+      expect(strategy.cache_ms).toBeGreaterThan(0);
+    });
+  });
+
+  describe("policy", () => {
+    it("should use password generator policy", () => {
+      const legacy = mock<UsernameGenerationServiceAbstraction>();
+      const strategy = new SubaddressGeneratorStrategy(legacy);
+
+      expect(strategy.policy).toBe(PolicyType.PasswordGenerator);
+    });
+  });
+
+  describe("generate()", () => {
+    it("should call the legacy service with the given options", async () => {
+      const legacy = mock<UsernameGenerationServiceAbstraction>();
+      const strategy = new SubaddressGeneratorStrategy(legacy);
+      const options = {
+        type: "website-name" as const,
+        email: "someone@example.com",
+      };
+
+      await strategy.generate(options);
+
+      expect(legacy.generateSubaddress).toHaveBeenCalledWith({
+        subaddressType: "website-name" as const,
+        subaddressEmail: "someone@example.com",
+      });
+    });
+  });
+});

libs/common/src/tools/generator/username/subaddress-generator-strategy.ts

@@ -0,0 +1,56 @@
+import { PolicyType } from "../../../admin-console/enums";
+import { Policy } from "../../../admin-console/models/domain/policy";
+import { GeneratorStrategy } from "../abstractions";
+import { DefaultPolicyEvaluator } from "../default-policy-evaluator";
+import { SUBADDRESS_SETTINGS } from "../key-definitions";
+import { NoPolicy } from "../no-policy";
+
+import { SubaddressGenerationOptions } from "./subaddress-generator-options";
+import { UsernameGenerationServiceAbstraction } from "./username-generation.service.abstraction";
+
+const ONE_MINUTE = 60 * 1000;
+
+/** Strategy for creating an email subaddress */
+export class SubaddressGeneratorStrategy
+  implements GeneratorStrategy<SubaddressGenerationOptions, NoPolicy>
+{
+  /** Instantiates the generation strategy
+   *  @param usernameService generates an email subaddress from an email address
+   */
+  constructor(private usernameService: UsernameGenerationServiceAbstraction) {}
+
+  /** {@link GeneratorStrategy.disk} */
+  get disk() {
+    return SUBADDRESS_SETTINGS;
+  }
+
+  /** {@link GeneratorStrategy.policy} */
+  get policy() {
+    // Uses password generator since there aren't policies
+    // specific to usernames.
+    return PolicyType.PasswordGenerator;
+  }
+
+  /** {@link GeneratorStrategy.cache_ms} */
+  get cache_ms() {
+    return ONE_MINUTE;
+  }
+
+  /** {@link GeneratorStrategy.evaluator} */
+  evaluator(policy: Policy) {
+    if (policy.type !== this.policy) {
+      const details = `Expected: ${this.policy}. Received: ${policy.type}`;
+      throw Error("Mismatched policy type. " + details);
+    }
+
+    return new DefaultPolicyEvaluator<SubaddressGenerationOptions>();
+  }
+
+  /** {@link GeneratorStrategy.generate} */
+  generate(options: SubaddressGenerationOptions) {
+    return this.usernameService.generateSubaddress({
+      subaddressEmail: options.email,
+      subaddressType: options.type,
+    });
+  }
+}