16534: Add example of calling other controller APIs.

[arvados.git] / lib / controller / example / controller.go

diff --git a/lib/controller/example/controller.go b/lib/controller/example/controller.go
index 03db99d4d6f8a588db28842f50269f39af29173e..5acc40e6d3fa7872fbe149795de55a26451cc70f 100644 (file)
--- a/lib/controller/example/controller.go
+++ b/lib/controller/example/controller.go
@@ -11,22 +11,37 @@ import (
        "git.arvados.org/arvados.git/sdk/go/arvados"
 )
 
-func New(cluster *arvados.Cluster) *Controller {
+func New(cluster *arvados.Cluster, parent arvados.API) *Controller {
        return &Controller{
                cluster: cluster,
+               parent:  parent,
        }
 }
 
 type Controller struct {
        cluster *arvados.Cluster
+       parent  arvados.API
 }
 
 func (ctrl *Controller) ExampleCount(ctx context.Context, opts arvados.ExampleCountOptions) (resp arvados.ExampleCountResponse, err error) {
+       // Example of direct database access
        tx, err := ctrlctx.CurrentTx(ctx)
        if err != nil {
                return
        }
        err = tx.QueryRowContext(ctx, `select count(*) from users`).Scan(&resp.Count)
+       if err != nil {
+               return
+       }
+
+       // Example of calling other controller APIs that are
+       // implemented in different packages
+       userlist, err := ctrl.parent.UserList(ctx, arvados.ListOptions{Limit: 0, Count: "exact"})
+       if err != nil {
+               return
+       }
+       resp.Count += userlist.ItemsAvailable
+
        return
 }