@atomicjolt/lti-client/src/client/launch.test.ts

Client Javascript libraries to handle LTI.

import { describe, expect, beforeEach, afterEach, it, vi } from "vitest";
import { LaunchSettings } from "../types";
import { STATE_KEY_PREFIX } from "../libs/constants";
import { ltiLaunch } from "./launch";

import {
  IdToken,
  MESSAGE_TYPE,
  MessageTypes,
  LTI_VERSION,
  LtiVersions,
  TARGET_LINK_URI_CLAIM,
  RESOURCE_LINK_CLAIM,
  DEPLOYMENT_ID,
  ROLES_CLAIM,
  ResourceLinkClaim,
} from "@atomicjolt/lti-types";

interface EventError {
  code: string;
  message: string;
}

interface LtiPlatformStorageEvent {
  data: {
    subject: string;
    message_id: string;
    error?: EventError;
    errormessage?: string;
    value: string;
  };
  origin: string;
}

const resourceLinkClaim: ResourceLinkClaim = {
  id: "134",
};

const idToken: IdToken = {
  sub: "1234567890",
  name: "John Doe",
  email: "johndoe@example.com",
  aud: "",
  azp: "",
  exp: 0,
  iat: 0,
  iss: "",
  nonce: "12343456",
  [MESSAGE_TYPE]: MessageTypes.LtiResourceLinkRequest,
  [LTI_VERSION]: LtiVersions.v1_3_0,
  [RESOURCE_LINK_CLAIM]: resourceLinkClaim,
  [DEPLOYMENT_ID]: "",
  [TARGET_LINK_URI_CLAIM]: "",
  [ROLES_CLAIM]: [],
  picture: "",
  given_name: "",
  family_name: "",
  middle_name: "",
  locale: "",
};

describe("launch", () => {
  const state = "thestate";
  const platformOIDCUrl =
    "https://canvas.instructure.com/api/lti/authorize_redirect";
  const origin = new URL(platformOIDCUrl).origin;
  let event: LtiPlatformStorageEvent;
  let settings: LaunchSettings;

  beforeEach(() => {
    document.body.innerHTML = `
      <form action="https://assessments.atomicjolt.xyz/lti_launches/" method="POST">
          <input type="hidden" name="state" id="state" value="state" />
          <input type="hidden" name="id_token" id="id_token" value="id_token" />
      </form>
      <div id="error" class="hidden">error</div>
    `;

    settings = {
      idToken,
      state,
      stateVerified: false,
      ltiStorageParams: {
        target: "_parent",
        originSupportBroken: true,
        platformOIDCUrl,
      },
    };

    event = {
      data: {
        subject: "lti.get_data.response",
        message_id: state,
        value: state,
      },
      origin,
    };
  });

  afterEach(() => {
    vi.restoreAllMocks();
    document.cookie = `${STATE_KEY_PREFIX}${state}=;Max-Age=-1`;
  });

  describe("validateLaunch", () => {
    it("calls postMessage", async () => {
      // Spy on postMessage to ensure it is called.
      const postMessageSpy = vi.spyOn(window, "postMessage");

      // Spy on addEventListener mock the response that will be sent to receiveMessage
      vi.spyOn(window, "addEventListener").mockImplementation(
        (eventName, func) => {
          if (eventName === "message") {
            const receiveMessage = func as Function;
            receiveMessage(event);
          }
          if (eventName === "load") {
            const f = func as Function;
            f();
          }
        }
      );

      await expect(ltiLaunch(settings)).resolves.toBeTruthy();
      await new Promise(process.nextTick);
      expect(postMessageSpy).toHaveBeenCalled();
    });

    it("returns false if the state is invalid", async () => {
      // Spy on postMessage to ensure it is called.
      const postMessageSpy = vi.spyOn(window, "postMessage");

      // Spy on addEventListener mock the response that will be sent to receiveMessage
      vi.spyOn(window, "addEventListener").mockImplementation(
        (eventName, func) => {
          if (eventName === "message") {
            const receiveMessage = func as Function;
            event.data.value = "badstate";
            receiveMessage(event);
          }
          if (eventName === "load") {
            const f = func as Function;
            f();
          }
        }
      );
      await expect(ltiLaunch(settings)).resolves.toBeFalsy();
      await new Promise(process.nextTick);
      expect(postMessageSpy).toHaveBeenCalled();
    });

    it("should return false when there is no ltiStorageParams", async () => {
      const settings: LaunchSettings = {
        state: "testState",
        idToken,
        stateVerified: false,
      };
      // Spy on addEventListener mock the response that will be sent to receiveMessage
      vi.spyOn(window, "addEventListener").mockImplementation(
        (eventName, func) => {
          if (eventName === "load") {
            const f = func as Function;
            f();
          }
        }
      );
      await expect(ltiLaunch(settings)).resolves.toBeFalsy();
    });
  });
});