Some initial stuff

dax/controller/balancer/balancer.go

@@ -672,6 +672,10 @@ func (b *Balancer) WorkersForTable(tx dax.Transaction, roleType dax.RoleType, qt
 	return workers, nil
 }
 
+func (b *Balancer) GetDatabaseNumberOfWorkers(tx dax.Transaction, roleType dax.RoleType, qdbid dax.QualifiedDatabaseID) (int, error) {
+	return b.current.WorkerCount(tx, roleType, qdbid)
+}
+
 func (b *Balancer) removeJob(tx dax.Transaction, roleType dax.RoleType, qdbid dax.QualifiedDatabaseID, job dax.Job) (InternalDiffs, error) {
 	if addr, ok, err := b.workerForJob(tx, roleType, qdbid, job); err != nil {
 		return nil, errors.Wrapf(err, "getting worker for job: %s", job)

dax/controller/controller.go

@@ -784,6 +784,19 @@ func (c *Controller) Databases(ctx context.Context, orgID dax.OrganizationID, id
 	return c.Schemar.Databases(tx, orgID, ids...)
 }
 
+// get the list of workers being used by a database
+func (c *Controller) GetDatabaseNumberOfWorkers(ctx context.Context, qdbid dax.QualifiedDatabaseID) (int, error) {
+	tx, err := c.Transactor.BeginTx(ctx, false)
+	if err != nil {
+		return -1, errors.Wrap(err, "beginning tx")
+	}
+	defer tx.Rollback()
+
+	// get the number of workers for the database from the balancer
+	workers, err := c.Balancer.GetDatabaseNumberOfWorkers(tx, qdbid)
+
+}
+
 // CreateTable adds a table to the schemar, and then sends directives to all
 // affected nodes based on the change.
 func (c *Controller) CreateTable(ctx context.Context, qtbl *dax.QualifiedTable) error {

dax/controller/http/handler.go

@@ -25,6 +25,7 @@ func Handler(c *controller.Controller) http.Handler {
 	router.HandleFunc("/database-by-name", server.postDatabaseByName).Methods("POST").Name("PostDatabaseByName")
 	router.HandleFunc("/databases", server.postDatabases).Methods("POST").Name("PostDatabases")
 	router.HandleFunc("/database/options", server.patchDatabaseOptions).Methods("PATCH").Name("PatchDatabaseOptions")
+	router.HandleFunc("/database-number-of-workers", server.getDatabaseNumberOfWorkers).Methods("GET").Name("DatabaseWorkers")
 
 	router.HandleFunc("/create-table", server.postCreateTable).Methods("POST").Name("PostCreateTable")
 	router.HandleFunc("/drop-table", server.postDropTable).Methods("POST").Name("PostDropTable")
@@ -214,6 +215,45 @@ func (s *server) patchDatabaseOptions(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+// get the number of workers for a database
+// receive request
+
+// decode the id
+
+// send the id into the controller, get the number of workers back
+
+// send that number back to the client via request
+
+// create a response struct
+func (s *server) getDatabaseNumberOfWorkers(w http.ResponseWriter, r *http.Request) {
+	// get the context
+	ctx := r.Context()
+
+	// create a variable to hold the id
+	var id dax.QualifiedDatabaseID
+
+	// for now, fill the id with a hard-coded value
+	id = dax.QualifiedDatabaseID{
+		OrganizationID: dax.OrganizationID("org1"),
+		DatabaseID:     dax.DatabaseID("db1"),
+	}
+
+	// send the id into the controller, get the number of workers back
+	numWorkers, err := s.controller.GetDatabaseNumberOfWorkers(ctx, id)
+
+	// handle error
+	if err != nil {
+		http.Error(w, errors.MarshalJSON(err), http.StatusBadRequest)
+		return
+	}
+
+	// send the number back to the client
+	if err := json.NewEncoder(w).Encode(numWorkers); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+}
+
 // DatabaseOptionRequest represents a change to a database option. The thinking
 // is to only support changing one database option at a time to keep the
 // implementation sane. At time of writing, only WorkersMin is supported.