Write up TODO

TODO

@@ -0,0 +1,71 @@
+1.
+Gracefull Shutdown
+
+2.
+base port is return port
+base port + 1 is port mapping port
+base port + 2 is first queue port
+
+server creates port mapping ON START, and moves jobs started more than 24 hours prior to now into QUEUE from RUNNING
+
+server supplies an infinite push of port mapping on base_port + 1
+worker gets port mapping from server using pull on base_port + 1
+
+QueuePort bucket
+    key: PortNum
+    Value: QueueName
+
+    get access:
+        Cursor iterates over Key/Value pairs
+
+    set access:
+        Ports are never overwritten, but new ports can be added
+
+    interaction:
+        base_port: usize,
+        queues: BTreeSet<String>
+
+        queue_port_bucket = store.bucket();
+
+        store = store.write_lock();
+
+        let read_txn = store.read_txn();
+        let write_txn = store.write_txn();
+
+        let queue_map = lock(write_txn, |write_txn| {
+            let cursor = read_txn.cursor();
+
+            let (unused_queues, queue_map) = cursor
+                .iter()
+                .fold(Ok((queues, BTreeMap::new())), |acc, (port, queue)| {
+                    acc.and_then(|(mut queues, mut bm)| {
+                        port = parse_port(port)?;
+                        queue = parse_queue(queue)?;
+
+                        queues.remove(queue);
+                        bm.insert(queue, port);
+
+                        Ok((queues, bm))
+                    })
+                })?;
+
+            let start_port = queue_map.iter().max_by(|(_, v)| v).unwrap_or(base_port + 2);
+
+            let (queue_map, _) = unused_queues
+                .into_iter()
+                .fold(Ok((queue_map, start_port)), |acc, queue_name| {
+                    acc.and_then(|(mut bm, port_num)| {
+                        write_txn.set(port_num, queue_name)?;
+                        bm.insert(queue_name, port_num);
+
+                        Ok((bm, port_num + 1))
+                    })
+                })?;
+
+            Ok(queue_map)
+        })?;
+
+        write_txn.commit();
+        read_txn.commit();
+
+        Ok(queue_map)