GITBOOK-189: change request with no subject merged in GitBook

Author: manast

docs/gitbook/SUMMARY.md

@@ -84,6 +84,7 @@
   * [Max group size](bullmq-pro/groups/max-group-size.md)
   * [Pausing groups](bullmq-pro/groups/pausing-groups.md)
   * [Prioritized intra-groups](bullmq-pro/groups/prioritized.md)
+  * [Sandboxes for groups](bullmq-pro/groups/sandboxes-for-groups.md)
 * [Batches](bullmq-pro/batches.md)
 * [NestJs](bullmq-pro/nestjs/README.md)
   * [Producers](bullmq-pro/nestjs/producers.md)

docs/gitbook/bullmq-pro/groups/sandboxes-for-groups.md

@@ -0,0 +1,13 @@
+# Sandboxes for groups
+
+It is also possible to use [Sandboxes](../../guide/workers/sandboxed-processors.md) for processing groups.  It works essentially the same as in standard BullMQ, but you gain access to the "gid" property in the job object sent to your processor, for example:
+
+```typescript
+module.exports = function (job: SandboxedJobPro) {
+  expect(job).to.have.property('gid');
+  expect(job.opts).to.have.property('group');
+  expect(job.opts.group).to.have.property('id');
+  expect(job.opts.group.id).to.be.a('string');
+  expect(job.opts.group.id).to.equal(job.gid);
+};
+```