api: add support for deleting apps (#327)

* api: add support for deleting apps

Fixes #274

* functions: improve error name and description

* functions: fix test regression

fn/apps.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net/http"
 	"os"
 	"text/tabwriter"
 
@@ -79,6 +80,11 @@ func apps() cli.Command {
 					},
 				},
 			},
+			{
+				Name:   "delete",
+				Usage:  "delete an app",
+				Action: a.delete,
+			},
 		},
 	}
 }
@@ -249,3 +255,26 @@ func (a *appsCmd) storeApp(appName string, config map[string]string) error {
 	}
 	return nil
 }
+
+func (a *appsCmd) delete(c *cli.Context) error {
+	appName := c.Args().First()
+	if appName == "" {
+		return errors.New("error: deleting an app takes one argument, an app name")
+	}
+
+	if err := resetBasePath(a.Configuration); err != nil {
+		return fmt.Errorf("error setting endpoint: %v", err)
+	}
+
+	resp, err := a.AppsAppDelete(appName)
+	if err != nil {
+		return fmt.Errorf("error deleting app: %v", err)
+	}
+
+	if resp.StatusCode == http.StatusBadRequest {
+		return errors.New("could not delete this application - pending routes")
+	}
+
+	fmt.Println(appName, "deleted")
+	return nil
+}