feat(autoscale): add support for autoscale per proc type on an application (#89)

Author: helgi

api/appsettings.go

@@ -1,5 +1,10 @@
 package api
 
+import (
+	"bytes"
+	"text/template"
+)
+
 // AppSettings is the structure of an app's settings.
 type AppSettings struct {
 	// Owner is the app owner. It cannot be updated with AppSettings.Set(). See app.Transfer().
@@ -16,8 +21,9 @@ type AppSettings struct {
 	// Maintenance determines if the application is taken down for maintenance or not.
 	Maintenance *bool `json:"maintenance,omitempty"`
 	// Routable determines if the application should be exposed by the router.
-	Routable  *bool    `json:"routable,omitempty"`
-	Whitelist []string `json:"whitelist,omitempty"`
+	Routable  *bool                 `json:"routable,omitempty"`
+	Whitelist []string              `json:"whitelist,omitempty"`
+	Autoscale map[string]*Autoscale `json:"autoscale,omitempty"`
 }
 
 // NewRoutable returns a default value for the AppSettings.Routable field.
@@ -30,3 +36,28 @@ func NewRoutable() *bool {
 type Whitelist struct {
 	Addresses []string `json:"addresses"`
 }
+
+// String displays the Autoscale rule in a readable format.
+func (a Autoscale) String() string {
+	var doc bytes.Buffer
+	tmpl, err := template.New("autoscale").Parse(`Min Replicas: {{.Min}}
+Max Replicas: {{.Max}}
+CPU: {{.CPUPercent}}%`)
+	if err != nil {
+		panic(err)
+	}
+	if err := tmpl.Execute(&doc, a); err != nil {
+		panic(err)
+	}
+	return doc.String()
+}
+
+// Autoscales contains a hash of process types and the autoscale rules
+type Autoscales map[string]*Autoscale
+
+// Autoscale is a per proc type scaling information
+type Autoscale struct {
+	Min        int `json:"min"`
+	Max        int `json:"max"`
+	CPUPercent int `json:"cpu_percent"`
+}

api/appsettings_test.go

@@ -0,0 +1,32 @@
+package api
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestAutoscaleString(t *testing.T) {
+	a := Autoscale{}
+
+	expected := strings.TrimSpace(`Min Replicas: 0
+Max Replicas: 0
+CPU: 0%`)
+
+	if strings.TrimSpace(a.String()) != expected {
+		t.Errorf("Expected:\n\n%s\n\nGot:\n\n%s", expected, a.String())
+	}
+
+	a2 := Autoscale{
+		Min:        3,
+		Max:        8,
+		CPUPercent: 40,
+	}
+
+	expected2 := strings.TrimSpace(`Min Replicas: 3
+Max Replicas: 8
+CPU: 40%`)
+
+	if strings.TrimSpace(a2.String()) != expected2 {
+		t.Errorf("Expected:\n\n%s\n\nGot:\n\n%s", expected2, a2.String())
+	}
+}

appsettings/appsettings_test.go

@@ -19,6 +19,7 @@ const appSettingsFixture string = `
     "maintenance": true,
     "routable": true,
     "whitelist": ["1.2.3.4", "0.0.0.0/0"],
+    "autoscale": {"cmd": {"min": 3, "max": 8, "cpu_percent": 40}},
     "created": "2014-01-01T00:00:00UTC",
     "updated": "2014-01-01T00:00:00UTC",
     "uuid": "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75"
@@ -29,17 +30,18 @@ const appSettingsUnsetFixture string = `
 {
     "owner": "test",
     "app": "unset-test",
-	  "maintenance": true,
+    "maintenance": true,
     "routable": true,
     "whitelist": ["1.2.3.4", "0.0.0.0/0"],
+    "autoscale": {"cmd": {"min": 3, "max": 8, "cpu_percent": 40}},
     "created": "2014-01-01T00:00:00UTC",
     "updated": "2014-01-01T00:00:00UTC",
     "uuid": "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75"
 }
 `
 
-const appSettingsSetExpected string = `{"maintenance":true,"routable":true,"whitelist":["1.2.3.4","0.0.0.0/0"]}`
-const appSettingsUnsetExpected string = `{"maintenance":true,"routable":true,"whitelist":["1.2.3.4","0.0.0.0/0"]}`
+const appSettingsSetExpected string = `{"maintenance":true,"routable":true,"whitelist":["1.2.3.4","0.0.0.0/0"],"autoscale":{"cmd":{"min":3,"max":8,"cpu_percent":40}}}`
+const appSettingsUnsetExpected string = `{"maintenance":true,"routable":true,"whitelist":["1.2.3.4","0.0.0.0/0"],"autoscale":{"cmd":{"min":3,"max":8,"cpu_percent":40}}}`
 
 var trueVar = true
 
@@ -129,15 +131,29 @@ func TestAppSettingsSet(t *testing.T) {
 		Routable:    api.NewRoutable(),
 		Maintenance: &trueVar,
 		Whitelist:   []string{"1.2.3.4", "0.0.0.0/0"},
-		Created:     "2014-01-01T00:00:00UTC",
-		Updated:     "2014-01-01T00:00:00UTC",
-		UUID:        "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
+		Autoscale: map[string]*api.Autoscale{
+			"cmd": {
+				Min:        3,
+				Max:        8,
+				CPUPercent: 40,
+			},
+		},
+		Created: "2014-01-01T00:00:00UTC",
+		Updated: "2014-01-01T00:00:00UTC",
+		UUID:    "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
 	}
 
 	appSettingsVars := api.AppSettings{
 		Maintenance: &trueVar,
 		Routable:    api.NewRoutable(),
 		Whitelist:   []string{"1.2.3.4", "0.0.0.0/0"},
+		Autoscale: map[string]*api.Autoscale{
+			"cmd": {
+				Min:        3,
+				Max:        8,
+				CPUPercent: 40,
+			},
+		},
 	}
 
 	actual, err := Set(deis, "example-go", appSettingsVars)
@@ -169,15 +185,29 @@ func TestAppSettingsUnset(t *testing.T) {
 		Maintenance: &trueVar,
 		Routable:    api.NewRoutable(),
 		Whitelist:   []string{"1.2.3.4", "0.0.0.0/0"},
-		Created:     "2014-01-01T00:00:00UTC",
-		Updated:     "2014-01-01T00:00:00UTC",
-		UUID:        "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
+		Autoscale: map[string]*api.Autoscale{
+			"cmd": {
+				Min:        3,
+				Max:        8,
+				CPUPercent: 40,
+			},
+		},
+		Created: "2014-01-01T00:00:00UTC",
+		Updated: "2014-01-01T00:00:00UTC",
+		UUID:    "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
 	}
 
 	appSettingsVars := api.AppSettings{
 		Maintenance: &trueVar,
 		Routable:    api.NewRoutable(),
 		Whitelist:   []string{"1.2.3.4", "0.0.0.0/0"},
+		Autoscale: map[string]*api.Autoscale{
+			"cmd": {
+				Min:        3,
+				Max:        8,
+				CPUPercent: 40,
+			},
+		},
 	}
 
 	actual, err := Set(deis, "unset-test", appSettingsVars)
@@ -209,9 +239,16 @@ func TestAppSettingsList(t *testing.T) {
 		Maintenance: &trueVar,
 		Routable:    api.NewRoutable(),
 		Whitelist:   []string{"1.2.3.4", "0.0.0.0/0"},
-		Created:     "2014-01-01T00:00:00UTC",
-		Updated:     "2014-01-01T00:00:00UTC",
-		UUID:        "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
+		Autoscale: map[string]*api.Autoscale{
+			"cmd": {
+				Min:        3,
+				Max:        8,
+				CPUPercent: 40,
+			},
+		},
+		Created: "2014-01-01T00:00:00UTC",
+		Updated: "2014-01-01T00:00:00UTC",
+		UUID:    "de1bf5b5-4a72-4f94-a10c-d2a3741cdf75",
 	}
 
 	actual, err := List(deis, "example-go")