feat: add support for debounce function

packages/helix-shared-bounce/README.md

@@ -22,9 +22,28 @@
    .with(bounce, { responder: fast });
  ```
 
+## Disabling Bouncing for certain requests
+
+The plugin options can take a `debounce` function property that is called with the `request` and
+`context`. if it returns a non falsy value the wrapped function will not be bounced.
+
+```js
+
+function debounce(req, context) {
+  if (context.pathInfo.suffix === '/about') {
+    return true;
+  }
+  return false;
+}
+
+module.exports.main = wrap(main)
+   .with(bounce, { responder: fast, debounce });
+
+```
+
 ## Disabling Bouncing for Tests
 
 If you are testing a function that is using `bounce` locally, you might want to disable the bouncing for the duration of the test, because you would otherwise have
 to mock a larger part of the runtime.
 
-To disable bouncing for tests, set the `HELIX_DEBOUNCE` environment variable to any value.
+To disable bouncing for tests, set the `HELIX_DEBOUNCE` environment variable to any value.

packages/helix-shared-bounce/src/bounce.js

@@ -20,9 +20,11 @@ const timer = {
   setTimeout: async (delay) => new Promise((resolve) => setTimeout(resolve, delay)),
 };
 
-function bounce(func, { responder, timeout = 500 }) {
+function bounce(func, { responder, timeout = 500, debounce = () => '' }) {
   return async (request, context) => {
-    const id = request.headers.get('x-hlx-bounce-id') || process.env.HELIX_DEBOUNCE;
+    const id = request.headers.get('x-hlx-bounce-id')
+      || process.env.HELIX_DEBOUNCE
+      || debounce(request, context);
     if (id) {
       // use the provided bounce id
       context.invocation = context.invocation || {};

packages/helix-shared-bounce/test/bounce.test.js

@@ -73,8 +73,8 @@ describe('Bounce Wrapper Unit Tests', () => {
       invocation: {
       },
     });
-    assert.equal(response.status, 200, 'universal function should be executed');
-    assert.equal(slowBounceId, fastBounceId);
+    assert.strictEqual(response.status, 200, 'universal function should be executed');
+    assert.strictEqual(slowBounceId, fastBounceId);
     assert.ok((await response.text()).startsWith('ok, job '));
   });
 
@@ -117,9 +117,8 @@ describe('Bounce Wrapper Unit Tests', () => {
     }), {
       log,
     });
-    assert.equal(response.status, 200, 'universal function should be executed');
-    console.log(slowBounceId, fastBounceId);
-    assert.equal(slowBounceId, fastBounceId);
+    assert.strictEqual(response.status, 200, 'universal function should be executed');
+    assert.strictEqual(slowBounceId, fastBounceId);
     assert.ok((await response.text()).startsWith('I am ready soon, check status at '));
   });
 
@@ -201,4 +200,46 @@ describe('Bounce Wrapper Unit Tests', () => {
     });
     assert.equal(response.status, 502, 'failing bounce should become 502');
   });
+
+  it('Debounces with function', async () => {
+    let slowBounceId;
+
+    const slowfunction = async (_, context) => {
+      slowBounceId = context.invocation.bounceId;
+      return new Response(`ok, job ${context.invocation.bounceId} completed.`);
+    };
+
+    const actualfunct = wrap(slowfunction).with(bounce, { debounce: () => '1234' });
+
+    nock('http://localhost').post('/').reply(async function fakeruntime(uri, requestBody) {
+      const request = new Request(`http://localhost${uri}`, {
+        headers: this.req.headers,
+        body: JSON.stringify((requestBody)),
+        method: this.req.method,
+      });
+
+      const response = await actualfunct(request, {
+        log,
+        invocation: {
+        },
+      });
+      const body = await response.text();
+      return [response.status, body];
+    });
+
+    const response = await actualfunct(new Request('http://localhost', {
+      body: JSON.stringify({ foo: 'bar' }),
+      method: 'POST',
+      headers: {
+        'content-type': 'application/json',
+      },
+    }), {
+      log,
+      invocation: {
+      },
+    });
+    assert.strictEqual(response.status, 200, 'universal function should be executed');
+    assert.strictEqual(slowBounceId, '1234');
+    assert.ok((await response.text()).startsWith('ok, job '));
+  });
 });