Merge pull request #427 from colhom/release-channel

kube-aws: configurable release channel

multi-node/aws/pkg/config/config.go

@@ -114,6 +114,12 @@ const (
 	vpcLogicalName = "VPC"
 )
 
+var supportedReleaseChannels = map[string]bool{
+	"alpha":  true,
+	"beta":   true,
+	"stable": false,
+}
+
 func (c Cluster) Config() (*Config, error) {
 	config := Config{Cluster: c}
 	config.ETCDEndpoints = fmt.Sprintf("http://%s:2379", c.ControllerIP)
@@ -329,6 +335,12 @@ func (cfg Cluster) valid() error {
 	if cfg.ExternalDNSName == "" {
 		return errors.New("externalDNSName must be set")
 	}
+
+	releaseChannelSupported := supportedReleaseChannels[cfg.ReleaseChannel]
+	if !releaseChannelSupported {
+		return fmt.Errorf("releaseChannel %s is not supported", cfg.ReleaseChannel)
+	}
+
 	if cfg.CreateRecordSet {
 		if cfg.HostedZone == "" {
 			return errors.New("hostedZone cannot be blank when createRecordSet is true")

multi-node/aws/pkg/config/config_test.go

@@ -253,3 +253,59 @@ func TestIsSubdomain(t *testing.T) {
 	}
 
 }
+
+func TestReleaseChannel(t *testing.T) {
+
+	validConfigs := []struct {
+		conf    string
+		channel string
+	}{
+		{
+			conf: `
+releaseChannel: alpha
+`,
+			channel: "alpha",
+		},
+		{
+			conf: `
+releaseChannel: beta
+`,
+			channel: "beta",
+		},
+	}
+
+	invalidConfigs := []string{
+		`
+#TODO(chom): move this to validConfigs when stable is supported
+releaseChannel: stable # stable is not supported (yet).
+`,
+		`
+releaseChannel: non-existant #this release channel will never exist
+`,
+	}
+
+	for _, conf := range validConfigs {
+		confBody := minimalConfigYaml + conf.conf
+		c, err := ClusterFromBytes([]byte(confBody))
+		if err != nil {
+			t.Errorf("failed to parse config %s: %v", confBody, err)
+			continue
+		}
+		if c.ReleaseChannel != conf.channel {
+			t.Errorf(
+				"parsed release channel %s does not match config: %s",
+				c.ReleaseChannel,
+				confBody,
+			)
+		}
+	}
+
+	for _, conf := range invalidConfigs {
+		confBody := minimalConfigYaml + conf
+		_, err := ClusterFromBytes([]byte(confBody))
+		if err == nil {
+			t.Errorf("expected error parsing invalid config: %s", confBody)
+		}
+	}
+
+}

multi-node/aws/pkg/config/templates/cluster.yaml

@@ -9,13 +9,17 @@ clusterName: {{.ClusterName}}
 # for you.  Otherwise the deployer is responsible for making this name routable
 externalDNSName: {{.ExternalDNSName}}
 
+# CoreOS release channel to use. Currently supported options: [ alpha, beta ]
+# See coreos.com/releases for more information
+#releaseChannel: alpha
+
 # Set to true if you want kube-aws to create a Route53 A Record for you.
 #createRecordSet: false
 
 # TTL in seconds for the Route53 RecordSet created if createRecordSet is set to true.
 #recordSetTTL: 300
 
-# The name of the hosted zone to add the externalDNSName to, 
+# The name of the hosted zone to add the externalDNSName to,
 # E.g: "google.com".  This needs to already exist, kube-aws will not create
 # it for you.
 #hostedZone: ""