Add isAvailableOnDevice util (#53)

* Add `isAvailableOnDevice` util

* wip

src/api/passkey-api-client.ts

@@ -3,6 +3,7 @@ import {
  AddAuthenticatorResponse,
  AuthenticationOptsRequest,
  AuthenticationOptsResponse,
+ PasskeyAuthenticatorResponse,
  RegistrationOptsRequest,
  RegistrationOptsResponse,
  VerifyRequest,
@@ -24,43 +25,56 @@ export class PasskeyApiClient {
  }
 
  async registrationOptions({token, userName}: RegistrationOptsRequest): Promise<RegistrationOptsResponse> {
- const request = fetch(`${this.baseUrl}/client/user-authenticators/passkey/registration-options`, {
+ const response = fetch(`${this.baseUrl}/client/user-authenticators/passkey/registration-options`, {
  method: "POST",
  headers: this.buildHeaders(token),
  body: JSON.stringify({username: userName}),
  });
 
- return (await request).json();
+ return (await response).json();
  }
 
  async authenticationOptions({token}: AuthenticationOptsRequest): Promise<AuthenticationOptsResponse> {
- const request = fetch(`${this.baseUrl}/client/user-authenticators/passkey/authentication-options`, {
+ const response = fetch(`${this.baseUrl}/client/user-authenticators/passkey/authentication-options`, {
  method: "POST",
  headers: this.buildHeaders(token),
  body: JSON.stringify({}),
  });
 
- return (await request).json();
+ return (await response).json();
  }
 
  async addAuthenticator({token, ...rest}: AddAuthenticatorRequest): Promise<AddAuthenticatorResponse> {
- const request = fetch(`${this.baseUrl}/client/user-authenticators/passkey`, {
+ const response = fetch(`${this.baseUrl}/client/user-authenticators/passkey`, {
  method: "POST",
  headers: this.buildHeaders(token),
  body: JSON.stringify(rest),
  });
 
- return (await request).json();
+ return (await response).json();
  }
 
  async verify({token, ...rest}: VerifyRequest): Promise<VerifyResponse> {
- const request = fetch(`${this.baseUrl}/client/verify/passkey`, {
+ const response = fetch(`${this.baseUrl}/client/verify/passkey`, {
  method: "POST",
  headers: this.buildHeaders(token),
  body: JSON.stringify(rest),
  });
 
- return (await request).json();
+ return (await response).json();
+ }
+
+ async getPasskeyAuthenticator(credentialId: string): Promise<PasskeyAuthenticatorResponse> {
+ const response = await fetch(`${this.baseUrl}/client/user-authenticators/passkey?credentialId=${credentialId}`, {
+ method: "GET",
+ headers: this.buildHeaders(),
+ });
+
+ if (!response.ok) {
+ throw new Error(response.statusText);
+ }
+
+ return response.json();
  }
 
  private buildHeaders(token?: string) {

src/api/types.ts

@@ -45,3 +45,8 @@ export type VerifyResponse = {
  isVerified: boolean;
  accessToken?: string;
 };
+
+export type PasskeyAuthenticatorResponse = {
+ credentialId: string;
+ verifiedAt: string;
+};

src/passkey.ts

@@ -1,6 +1,7 @@
 import {startAuthentication, startRegistration} from "@simplewebauthn/browser";
 
 import {PasskeyApiClient} from "./api";
+import {AuthenticationResponseJSON, RegistrationResponseJSON} from "@simplewebauthn/types";
 
 type PasskeyOptions = {
  baseUrl: string;
@@ -14,6 +15,7 @@ type SignUpParams = {
 
 export class Passkey {
  public api: PasskeyApiClient;
+ private passkeyLocalStorageKey = "as_passkey_credential_id";
 
  constructor({baseUrl, tenantId}: PasskeyOptions) {
  this.api = new PasskeyApiClient({baseUrl, tenantId});
@@ -30,6 +32,10 @@ export class Passkey {
  token,
  });
 
+ if (addAuthenticatorResponse?.isVerified) {
+ this.storeCredentialAgainstDevice(registrationResponse);
+ }
+
  return addAuthenticatorResponse?.accessToken;
  }
 
@@ -51,6 +57,37 @@ export class Passkey {
  token: params?.token,
  });
 
+ if (verifyResponse?.isVerified) {
+ this.storeCredentialAgainstDevice(authenticationResponse);
+ }
+
  return verifyResponse?.accessToken;
  }
+
+ async isAvailableOnDevice() {
+ const credentialId = localStorage.getItem(this.passkeyLocalStorageKey);
+
+ if (!credentialId) {
+ return false;
+ }
+
+ try {
+ await this.api.getPasskeyAuthenticator(credentialId);
+
+ return true;
+ } catch {
+ return false;
+ }
+ }
+
+ private storeCredentialAgainstDevice({
+ id,
+ authenticatorAttachment,
+ }: AuthenticationResponseJSON | RegistrationResponseJSON) {
+ if (authenticatorAttachment === "cross-platform") {
+ return;
+ }
+
+ localStorage.setItem(this.passkeyLocalStorageKey, id);
+ }
 }