add validate tag for the purpose of required field (Azure#886)

* add validate tag for the purpose of required field

* import gopkg.in/go-playground/validator.v9

* apply gopkg.in/go-playground/validator.v9 for 2017-07-01 api model

* add handler for validation errors

glide.yaml

@@ -31,6 +31,10 @@ import:
   version: 4cdb38c072b86bf795d2c81de50784d9fdd6eb77
 - package: github.com/spf13/pflag
   version: e57e3eeb33f795204c1ca35f56c44f83227c6e66
+- package: gopkg.in/go-playground/validator.v9
+  version: v9.4.0
+- package: github.com/go-playground/universal-translator
+  version: v0.16.0
 testImport:
 - package: github.com/onsi/gomega
   version: ^1.1.0

pkg/api/v20170701/types.go

@@ -5,6 +5,9 @@ import (
 	"strings"
 )
 
+// The validate tag is used for validation
+// Reference to gopkg.in/go-playground/validator.v9
+
 // ResourcePurchasePlan defines resource plan as required by ARM
 // for billing purposes.
 type ResourcePurchasePlan struct {
@@ -18,7 +21,7 @@ type ResourcePurchasePlan struct {
 // resource definition in a JSON template.
 type ContainerService struct {
 	ID       string                `json:"id,omitempty"`
-	Location string                `json:"location,omitempty"`
+	Location string                `json:"location,omitempty" validate:"required"`
 	Name     string                `json:"name,omitempty"`
 	Plan     *ResourcePurchasePlan `json:"plan,omitempty"`
 	Tags     map[string]string     `json:"tags,omitempty"`
@@ -30,10 +33,10 @@ type ContainerService struct {
 // Properties represents the ACS cluster definition
 type Properties struct {
 	ProvisioningState       ProvisioningState        `json:"provisioningState,omitempty"`
-	OrchestratorProfile     *OrchestratorProfile     `json:"orchestratorProfile,omitempty"`
-	MasterProfile           *MasterProfile           `json:"masterProfile,omitempty"`
-	AgentPoolProfiles       []*AgentPoolProfile      `json:"agentPoolProfiles,omitempty"`
-	LinuxProfile            *LinuxProfile            `json:"linuxProfile,omitempty"`
+	OrchestratorProfile     *OrchestratorProfile     `json:"orchestratorProfile,omitempty" validate:"required"`
+	MasterProfile           *MasterProfile           `json:"masterProfile,omitempty" validate:"required"`
+	AgentPoolProfiles       []*AgentPoolProfile      `json:"agentPoolProfiles,omitempty" validate:"dive,required"`
+	LinuxProfile            *LinuxProfile            `json:"linuxProfile,omitempty" validate:"required"`
 	WindowsProfile          *WindowsProfile          `json:"windowsProfile,omitempty"`
 	ServicePrincipalProfile *ServicePrincipalProfile `json:"servicePrincipalProfile,omitempty"`
 	CustomProfile           *CustomProfile           `json:"customProfile,omitempty"`
@@ -50,8 +53,8 @@ type Properties struct {
 //    <NAME> is the name of the secret.
 //    <VERSION> (optional) is the version of the secret (default: the latest version)
 type ServicePrincipalProfile struct {
-	ClientID string `json:"clientId,omitempty"`
-	Secret   string `json:"secret,omitempty"`
+	ClientID string `json:"clientId,omitempty" validate:"required"`
+	Secret   string `json:"secret,omitempty" validate:"required"`
 }
 
 // CustomProfile specifies custom properties that are used for
@@ -62,19 +65,19 @@ type CustomProfile struct {
 
 // LinuxProfile represents the Linux configuration passed to the cluster
 type LinuxProfile struct {
-	AdminUsername string `json:"adminUsername"`
+	AdminUsername string `json:"adminUsername" validate:"required"`
 
 	SSH struct {
 		PublicKeys []struct {
 			KeyData string `json:"keyData"`
-		} `json:"publicKeys"`
-	} `json:"ssh"`
+		} `json:"publicKeys" validate:"required,len=1"`
+	} `json:"ssh" validate:"required"`
 }
 
 // WindowsProfile represents the Windows configuration passed to the cluster
 type WindowsProfile struct {
-	AdminUsername string `json:"adminUsername,omitempty"`
-	AdminPassword string `json:"adminPassword,omitempty"`
+	AdminUsername string `json:"adminUsername,omitempty" validate:"required"`
+	AdminPassword string `json:"adminPassword,omitempty" validate:"required"`
 }
 
 // ProvisioningState represents the current state of container service resource.
@@ -98,19 +101,19 @@ const (
 
 // OrchestratorProfile contains Orchestrator properties
 type OrchestratorProfile struct {
-	OrchestratorType    OrchestratorType    `json:"orchestratorType"`
+	OrchestratorType    OrchestratorType    `json:"orchestratorType" validate:"required"`
 	OrchestratorVersion OrchestratorVersion `json:"orchestratorVersion"`
 }
 
 // MasterProfile represents the definition of master cluster
 type MasterProfile struct {
-	Count                    int    `json:"count"`
-	DNSPrefix                string `json:"dnsPrefix"`
-	VMSize                   string `json:"vmSize"`
-	OSDiskSizeGB             int    `json:"osDiskSizeGB,omitempty"`
+	Count                    int    `json:"count" validate:"required,eq=1|eq=3|eq=5"`
+	DNSPrefix                string `json:"dnsPrefix" validate:"required"`
+	VMSize                   string `json:"vmSize" validate:"required"`
+	OSDiskSizeGB             int    `json:"osDiskSizeGB,omitempty" validate:"min=0,max=1023"`
 	VnetSubnetID             string `json:"vnetSubnetID,omitempty"`
 	FirstConsecutiveStaticIP string `json:"firstConsecutiveStaticIP,omitempty"`
-	StorageProfile           string `json:"storageProfile,omitempty"`
+	StorageProfile           string `json:"storageProfile,omitempty" validate:"eq=StorageAccount|eq=ManagedDisks|len=0"`
 
 	// subnet is internal
 	subnet string
@@ -124,14 +127,14 @@ type MasterProfile struct {
 // daemons that register with the master and offer resources to
 // host applications in containers.
 type AgentPoolProfile struct {
-	Name           string `json:"name"`
-	Count          int    `json:"count"`
-	VMSize         string `json:"vmSize"`
-	OSDiskSizeGB   int    `json:"osDiskSizeGB,omitempty"`
+	Name           string `json:"name" validate:"required"`
+	Count          int    `json:"count" validate:"required,min=1,max=100"`
+	VMSize         string `json:"vmSize" validate:"required"`
+	OSDiskSizeGB   int    `json:"osDiskSizeGB,omitempty" validate:"min=0,max=1023"`
 	DNSPrefix      string `json:"dnsPrefix"`
 	FQDN           string `json:"fqdn"`
-	Ports          []int  `json:"ports,omitempty"`
-	StorageProfile string `json:"storageProfile"`
+	Ports          []int  `json:"ports,omitempty" validate:"dive,min=1,max=65535"`
+	StorageProfile string `json:"storageProfile" validate:"eq=StorageAccount|eq=ManagedDisks|len=0"`
 	VnetSubnetID   string `json:"vnetSubnetID,omitempty"`
 	// OSType is the operating system type for agents
 	// Set as nullable to support backward compat because