test(lambda-tiler): implement test suite for tileset path function

packages/lambda-tiler/src/routes/__tests__/link.test.ts

@@ -0,0 +1,99 @@
+import { strictEqual } from 'node:assert';
+import { afterEach, before, describe, test } from 'node:test';
+
+import { ConfigProviderMemory } from '@basemaps/config';
+import { Epsg } from '@basemaps/geo';
+import { createSandbox } from 'sinon';
+
+import { FakeData, Imagery3857 } from '../../__tests__/config.data.js';
+import { mockRequest } from '../../__tests__/xyz.util.js';
+import { handler } from '../../index.js';
+import { ConfigLoader } from '../../util/config.loader.js';
+
+const NAME = 'tileset';
+const PATH = `/v1/link/${NAME}`;
+
+describe('/v1/link/:tileSet', () => {
+  const config = new ConfigProviderMemory();
+  const sandbox = createSandbox();
+
+  before(() => {
+    sandbox.stub(ConfigLoader, 'getDefaultConfig').resolves(config);
+  });
+
+  afterEach(() => {
+    config.objects.clear();
+  });
+
+  /**
+   * 3xx status responses
+   */
+
+  // tileset found, has one layer, has '3857' entry, imagery found > 302 response
+  test('success: redirect to pre-zoomed imagery', async () => {
+    config.put(FakeData.tileSetRaster(NAME));
+    config.put(Imagery3857);
+
+    const req = mockRequest(PATH);
+    const res = await handler.router.handle(req);
+
+    strictEqual(res.status, 302);
+    strictEqual(res.statusDescription, 'Redirect to pre-zoomed imagery');
+  });
+
+  /**
+   * 4xx status responses
+   */
+
+  // tileset not found > 404 response
+  test('failure: tileset not found', async () => {
+    const req = mockRequest(PATH);
+    const res = await handler.router.handle(req);
+
+    strictEqual(res.status, 404);
+    strictEqual(res.statusDescription, 'Tileset not found');
+  });
+
+  // tileset found, has more than one layer > 400 response
+  test('failure: too many layers', async () => {
+    const tileSet = FakeData.tileSetRaster(NAME);
+
+    // add another layer
+    tileSet.layers.push(tileSet.layers[0]);
+
+    config.put(tileSet);
+
+    const req = mockRequest(PATH);
+    const res = await handler.router.handle(req);
+
+    strictEqual(res.status, 400);
+    strictEqual(res.statusDescription, 'Too many layers');
+  });
+
+  // tileset found, has one layer, no '3857' entry > 400 response
+  test("failure: no imagery for '3857' projection", async () => {
+    const tileSet = FakeData.tileSetRaster(NAME);
+
+    // delete '3857' entry
+    delete tileSet.layers[0][Epsg.Google.code];
+
+    config.put(tileSet);
+
+    const req = mockRequest(PATH);
+    const res = await handler.router.handle(req);
+
+    strictEqual(res.status, 400);
+    strictEqual(res.statusDescription, "No imagery for '3857' projection");
+  });
+
+  // tileset found, has one layer, has '3857' entry, imagery not found > 400 response
+  test('failure: imagery not found', async () => {
+    config.put(FakeData.tileSetRaster(NAME));
+
+    const req = mockRequest(PATH);
+    const res = await handler.router.handle(req);
+
+    strictEqual(res.status, 400);
+    strictEqual(res.statusDescription, 'Imagery not found');
+  });
+});

packages/lambda-tiler/src/routes/link.ts

@@ -12,30 +12,36 @@ export interface LinkGet {
 
 /**
  * Given a tileset, this function redirects the client to a Basemaps URL that is already zoomed to
- * the extent of the tileset's imagery. Otherwise, this function returns an 4XX status and message.
+ * the extent of the tileset's imagery. Otherwise, this function returns an 4xx status and message.
  *
  * @param tileSet - The id of the tileset.
  * @example "ashburton-2023-0.1m"
  */
 export async function linkGet(req: LambdaHttpRequest<LinkGet>): Promise<LambdaHttpResponse> {
   const config = await ConfigLoader.load(req);
 
+  // get tileset
+
   req.timer.start('tileset:load');
   const tileSet = await config.TileSet.get(req.params.tileSet);
   req.timer.end('tileset:load');
-  if (tileSet == null) return new LambdaHttpResponse(404, 'Tileset not found');
 
+  if (tileSet == null) return new LambdaHttpResponse(404, 'Tileset not found');
   if (tileSet.layers.length !== 1) return new LambdaHttpResponse(400, 'Too many layers');
 
+  // get imagery
+
   const imageryId = tileSet.layers[0][Epsg.Google.code];
   if (imageryId === undefined) return new LambdaHttpResponse(400, "No imagery for '3857' projection");
 
   const imagery = await config.Imagery.get(imageryId);
   if (imagery == null) return new LambdaHttpResponse(400, 'Imagery not found');
 
+  // do redirect
+
   const url = getPreviewUrl({ imagery });
 
-  return new LambdaHttpResponse(302, 'Redirecting to pre-zoomed imagery', {
+  return new LambdaHttpResponse(302, 'Redirect to pre-zoomed imagery', {
     location: `/${url.slug}?i=${url.name}`,
   });
 }