From ef9be2a5aca04a3e60b81ff944c8681c076eab80 Mon Sep 17 00:00:00 2001
From: "Jonathan Leibiusky @xetorthio" <ionathan@gmail.com>
Date: Thu, 7 Sep 2017 17:05:05 -0300
Subject: [PATCH] Add support for out of capacity error message

---
 handlers/new_instance.go   | 6 ++++++
 provisioner/provisioner.go | 7 +++++++
 www/assets/app.js          | 2 ++
 3 files changed, 15 insertions(+)

diff --git a/handlers/new_instance.go b/handlers/new_instance.go
index 545710f..75fe7cc 100644
--- a/handlers/new_instance.go
+++ b/handlers/new_instance.go
@@ -2,10 +2,12 @@ package handlers
 
 import (
 	"encoding/json"
+	"fmt"
 	"log"
 	"net/http"
 
 	"github.com/gorilla/mux"
+	"github.com/play-with-docker/play-with-docker/provisioner"
 	"github.com/play-with-docker/play-with-docker/pwd"
 	"github.com/play-with-docker/play-with-docker/pwd/types"
 )
@@ -25,6 +27,10 @@ func NewInstance(rw http.ResponseWriter, req *http.Request) {
 		if pwd.SessionComplete(err) {
 			rw.WriteHeader(http.StatusConflict)
 			return
+		} else if provisioner.OutOfCapacity(err) {
+			rw.WriteHeader(http.StatusServiceUnavailable)
+			fmt.Fprintln(rw, `{"error": "out_of_capacity"}`)
+			return
 		}
 		log.Println(err)
 		rw.WriteHeader(http.StatusInternalServerError)
diff --git a/provisioner/provisioner.go b/provisioner/provisioner.go
index cabd142..3e1e161 100644
--- a/provisioner/provisioner.go
+++ b/provisioner/provisioner.go
@@ -1,12 +1,19 @@
 package provisioner
 
 import (
+	"errors"
 	"io"
 	"net"
 
 	"github.com/play-with-docker/play-with-docker/pwd/types"
 )
 
+var OutOfCapacityError = errors.New("OutOfCapacity")
+
+func OutOfCapacity(e error) bool {
+	return e == OutOfCapacityError
+}
+
 type InstanceProvisionerApi interface {
 	InstanceNew(session *types.Session, conf types.InstanceConfig) (*types.Instance, error)
 	InstanceDelete(session *types.Session, instance *types.Instance) error
diff --git a/www/assets/app.js b/www/assets/app.js
index 553c7b2..53a8694 100644
--- a/www/assets/app.js
+++ b/www/assets/app.js
@@ -127,6 +127,8 @@
       }, function(response) {
         if (response.status == 409) {
           $scope.showAlert('Max instances reached', 'Maximum number of instances reached')
+        } else if (response.status == 503 && response.data.error == 'out_of_capacity') {
+          $scope.showAlert('Out Of Capacity', 'We are really sorry. But we are currently out of capacity and cannot create new instances. Please try again later.')
         }
       }).finally(function() {
         updateNewInstanceBtnState(false);