✨ Added ability to remove scheduled jobs

closes #119

- A future use-case which this feature caters for is allowing to migrate "post scheduler" to use job manager instead of managing scheduling itself
- removeJob method will be needed to allow "rescheduling" of the post

ghost/job-manager/lib/job-manager.js

@@ -111,6 +111,21 @@ class JobManager {
         return this.bree.start(name);
     }
 
+    /**
+     * Removes a job from sqcheduled (offloaded) jobs queue.
+     * There is no way to remove jovs from in-line (same event loop) jobs
+     * added through `addJob` method.
+     * The method will throw an Error if job with provided name does not exist.
+     *
+     * NOTE: current implementation does not guarante running job termination
+     *       for details see https://github.com/breejs/bree/pull/64
+     *
+     * @param {String} name - job name
+     */
+    async removeJob(name) {
+        await this.bree.remove(name);
+    }
+
     /**
      * @param {import('p-wait-for').Options} [options]
      */

ghost/job-manager/test/job-manager.test.js

@@ -59,7 +59,7 @@ describe('Job Manager', function () {
         });
     });
 
-    describe('Schedule Job', function () {
+    describe('Schedule a Job', function () {
         it('fails to schedule for invalid scheduling expression', function () {
             const jobManager = new JobManager(logging);
 
@@ -115,6 +115,22 @@ describe('Job Manager', function () {
         });
     });
 
+    describe('Remove a Job', function () {
+        it('removes a scheduled job from the queue', async function () {
+            const jobManager = new JobManager(logging);
+
+            const timeInTenSeconds = new Date(Date.now() + 10);
+            const jobPath = path.resolve(__dirname, './jobs/simple.js');
+
+            jobManager.scheduleJob(timeInTenSeconds, jobPath, null, 'job-in-ten');
+            jobManager.bree.config.jobs[0].name.should.equal('job-in-ten');
+
+            await jobManager.removeJob('job-in-ten');
+
+            should(jobManager.bree.config.jobs[0]).be.undefined;
+        });
+    });
+
     describe('Shutdown', function () {
         it('gracefully shuts down a synchronous jobs', async function () {
             const jobManager = new JobManager(logging);