Merge pull request #259 from nulib/5205-retrieve-user-token

Add /auth/token route

node/src/api/api-token.js

@@ -14,6 +14,7 @@ function emptyToken() {
     isLoggedIn: false,
   };
 }
+
 class ApiToken {
   constructor(signedToken) {
     if (signedToken) {
@@ -79,6 +80,10 @@ class ApiToken {
     return this.update();
   }
 
+  expireAt(dateTime) {
+    this.token.exp = Math.floor(Number(dateTime) / 1000);
+  }
+
   update() {
     this._updated = true;
     return this;

node/src/handlers/get-auth-token.js

@@ -0,0 +1,51 @@
+const { wrap } = require("./middleware");
+const Honeybadger = require("../honeybadger-setup");
+
+const DEFAULT_TTL = 86400; // one day
+const MAX_TTL = DEFAULT_TTL * 7; // one week;
+
+const makeError = (code, message) => {
+  return {
+    statusCode: code,
+    headers: {
+      "Content-Type": "text/plain",
+    },
+    body: message,
+  };
+};
+
+const present = (value) =>
+  value !== undefined && value !== null && value !== "";
+
+/**
+ * Token - Returns auth token for current user with requested expiration
+ *
+ */
+exports.handler = wrap(async (event) => {
+  try {
+    const ttl = event.queryStringParameters?.ttl;
+    if (present(ttl) && ttl.match(/\D/)) {
+      return makeError(400, `'${ttl}' is not a valid value for ttl`);
+    }
+    const ttl_in_seconds = Number(ttl) || DEFAULT_TTL;
+    if (ttl_in_seconds > MAX_TTL) {
+      return makeError(400, `ttl cannot exceed ${MAX_TTL} seconds`);
+    }
+
+    const token = event.userToken;
+    const expiration = new Date(new Date().getTime() + ttl_in_seconds * 1000);
+    expiration.setMilliseconds(0);
+    token.expireAt(expiration);
+
+    return {
+      statusCode: 200,
+      body: JSON.stringify({
+        token: token.sign(),
+        expires: expiration.toISOString(),
+      }),
+    };
+  } catch (error) {
+    await Honeybadger.notifyAsync(error);
+    return makeError(401, "Error verifying API token: " + error.message);
+  }
+});

node/test/integration/get-auth-token.test.js

@@ -0,0 +1,136 @@
+"use strict";
+
+const chai = require("chai");
+const expect = chai.expect;
+const jwt = require("jsonwebtoken");
+
+const getAuthTokenHandler = requireSource("handlers/get-auth-token");
+
+// Utility functions to calculate the number of seconds or milliseconds from the epoch plus
+// an offset in seconds, but with one-second resolution
+const fromNowSeconds = (seconds) =>
+  Math.floor((new Date().getTime() + seconds * 1000) / 1000);
+
+describe("auth token", function () {
+  helpers.saveEnvironment();
+  let payload;
+
+  beforeEach(() => {
+    payload = {
+      iss: "https://example.com",
+      sub: "user123",
+      name: "Some One",
+      exp: Math.floor(Number(new Date()) / 1000) + 12 * 60 * 60,
+      iat: Math.floor(Number(new Date()) / 1000),
+      email: "user@example.com",
+    };
+  });
+
+  it("works with anonymous users", async () => {
+    const event = helpers.mockEvent("GET", "/auth/token").render();
+
+    const expectedExpiration = fromNowSeconds(86400);
+    const result = await getAuthTokenHandler.handler(event);
+    expect(result.statusCode).to.eq(200);
+    const body = JSON.parse(result.body);
+
+    // Built-in Date will be in millis and our expiration is in seconds
+    expect(Date.parse(body.expires)).to.be.within(
+      (expectedExpiration - 1) * 1000,
+      (expectedExpiration + 1) * 1000
+    );
+
+    const resultToken = jwt.verify(body.token, process.env.API_TOKEN_SECRET);
+    expect(resultToken.exp).to.be.within(
+      expectedExpiration - 1,
+      expectedExpiration + 1
+    );
+    expect(resultToken.isLoggedIn).to.eq(false);
+  });
+
+  it("returns a token with a default ttl of 1 day", async () => {
+    const token = jwt.sign(payload, process.env.API_TOKEN_SECRET);
+    const event = helpers
+      .mockEvent("GET", "/auth/token")
+      .headers({
+        Cookie: `${process.env.API_TOKEN_NAME}=${token};`,
+      })
+      .render();
+
+    const expectedExpiration = fromNowSeconds(86400);
+    const result = await getAuthTokenHandler.handler(event);
+    expect(result.statusCode).to.eq(200);
+    const body = JSON.parse(result.body);
+
+    // Built-in Date will be in millis and our expiration is in seconds
+    expect(Date.parse(body.expires)).to.be.within(
+      (expectedExpiration - 1) * 1000,
+      (expectedExpiration + 1) * 1000
+    );
+
+    const resultToken = jwt.verify(body.token, process.env.API_TOKEN_SECRET);
+    expect(resultToken.exp).to.be.within(
+      expectedExpiration - 1,
+      expectedExpiration + 1
+    );
+    expect(resultToken.name).to.eq("Some One");
+  });
+
+  it("returns a token with the requested ttl", async () => {
+    const token = jwt.sign(payload, process.env.API_TOKEN_SECRET);
+    const ttl = 3600 * 18; // 18 hours
+    const event = helpers
+      .mockEvent("GET", "/auth/token")
+      .queryParams({ ttl: ttl.toString() })
+      .headers({
+        Cookie: `${process.env.API_TOKEN_NAME}=${token};`,
+      })
+      .render();
+
+    const expectedExpiration = fromNowSeconds(ttl);
+    const result = await getAuthTokenHandler.handler(event);
+    expect(result.statusCode).to.eq(200);
+    const body = JSON.parse(result.body);
+
+    // Built-in Date will be in millis and our expiration is in seconds
+    expect(Date.parse(body.expires)).to.be.within(
+      (expectedExpiration - 1) * 1000,
+      (expectedExpiration + 1) * 1000
+    );
+
+    const resultToken = jwt.verify(body.token, process.env.API_TOKEN_SECRET);
+    expect(resultToken.exp).to.be.within(
+      expectedExpiration - 1,
+      expectedExpiration + 1
+    );
+    expect(resultToken.name).to.eq("Some One");
+  });
+
+  it("rejects a request with a non-numeric ttl", async () => {
+    const token = jwt.sign(payload, process.env.API_TOKEN_SECRET);
+    const event = helpers
+      .mockEvent("GET", "/auth/token")
+      .queryParams({ ttl: "blargh" })
+      .headers({
+        Cookie: `${process.env.API_TOKEN_NAME}=${token};`,
+      })
+      .render();
+    const result = await getAuthTokenHandler.handler(event);
+    expect(result.statusCode).to.eq(400);
+    expect(result.body).to.eq("'blargh' is not a valid value for ttl");
+  });
+
+  it("rejects a request with a ttl that's too high", async () => {
+    const token = jwt.sign(payload, process.env.API_TOKEN_SECRET);
+    const event = helpers
+      .mockEvent("GET", "/auth/token")
+      .queryParams({ ttl: "864000" })
+      .headers({
+        Cookie: `${process.env.API_TOKEN_NAME}=${token};`,
+      })
+      .render();
+    const result = await getAuthTokenHandler.handler(event);
+    expect(result.statusCode).to.eq(400);
+    expect(result.body).to.eq("ttl cannot exceed 604800 seconds");
+  });
+});

template.yaml

@@ -200,6 +200,30 @@ Resources:
             ApiId: !Ref dcApi
             Path: /auth/logout
             Method: GET
+  getAuthTokenFunction:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: handlers/get-auth-token.handler
+      Description: Function to retrieve raw JWT.
+      #* Layers:
+      #*   - !Ref apiDependencies
+      Environment:
+        Variables:
+          NUSSO_API_KEY: !Ref NussoApiKey
+          NUSSO_BASE_URL: !Ref NussoBaseUrl
+      Events:
+        ApiGet:
+          Type: HttpApi
+          Properties:
+            ApiId: !Ref dcApi
+            Path: /auth/token
+            Method: GET
+        ApiHead:
+          Type: HttpApi
+          Properties:
+            ApiId: !Ref dcApi
+            Path: /auth/token
+            Method: HEAD
   getAuthWhoAmIFunction:
     Type: AWS::Serverless::Function
     Properties: