[feature] Prevent overwriting existing cluster resources in output di…

…rectories (#2581) * Prevent overwriting existing folder when using the deploy command
Azure · Apr 10, 2018 · 45e4a22 · 45e4a22
1 parent cf0f10d
commit 45e4a22
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Showing 2 changed files with 13 additions and 5 deletions.
diff --git a/cmd/deploy.go b/cmd/deploy.go
@@ -35,6 +35,7 @@ type deployCmd struct {
 	dnsPrefix         string
 	autoSuffix        bool
 	outputDirectory   string // can be auto-determined from clusterDefinition
+	forceOverwrite    bool
 	caCertificatePath string
 	caPrivateKeyPath  string
 	classicMode       bool
@@ -75,6 +76,7 @@ func newDeployCmd() *cobra.Command {
 	f.StringVar(&dc.caPrivateKeyPath, "ca-private-key-path", "", "path to the CA private key to use for Kubernetes PKI assets")
 	f.StringVarP(&dc.resourceGroup, "resource-group", "g", "", "resource group to deploy to")
 	f.StringVarP(&dc.location, "location", "l", "", "location to deploy to")
+	f.BoolVarP(&dc.forceOverwrite, "force-overwrite", "f", false, "automatically overwrite existing files in the output directory")
 
 	addAuthFlags(&dc.authArgs, f)
 
@@ -174,6 +176,10 @@ func autofillApimodel(dc *deployCmd) {
 		dc.outputDirectory = path.Join("_output", dc.containerService.Properties.MasterProfile.DNSPrefix)
 	}
 
+	if _, err := os.Stat(dc.outputDirectory); !dc.forceOverwrite && err == nil {
+		log.Fatalf(fmt.Sprintf("Output directory already exists and forceOverwrite flag is not set: %s", dc.outputDirectory))
+	}
+
 	if dc.resourceGroup == "" {
 		dnsPrefix := dc.containerService.Properties.MasterProfile.DNSPrefix
 		log.Warnf("--resource-group was not specified. Using the DNS prefix from the apimodel as the resource group name: %s", dnsPrefix)

diff --git a/docs/kubernetes/deploy.md b/docs/kubernetes/deploy.md
@@ -39,15 +39,15 @@ Run `acs-engine deploy` with the appropriate arguments:
 ```
 $ acs-engine deploy --subscription-id 51ac25de-afdg-9201-d923-8d8e8e8e8e8e \
     --dns-prefix contoso-apple --location westus2 \
-    --auto-suffix --api-model examples/kubernetes.json
+    --api-model examples/kubernetes.json
 
-WARN[0005] apimodel: missing masterProfile.dnsPrefix will use "contoso-apple-59769a59"
-WARN[0005] --resource-group was not specified. Using the DNS prefix from the apimodel as the resource group name: contoso-apple-59769a59
+WARN[0005] apimodel: missing masterProfile.dnsPrefix will use "contoso-apple"
+WARN[0005] --resource-group was not specified. Using the DNS prefix from the apimodel as the resource group name: contoso-apple
 WARN[0008] apimodel: ServicePrincipalProfile was empty, creating application...
 WARN[0017] created application with applicationID (7e2d433f-d039-48b8-87dc-83fa4dfa38d4) and servicePrincipalObjectID (db6167e1-aeed-407a-b218-086589759442).
 WARN[0017] apimodel: ServicePrincipalProfile was empty, assigning role to application...
-INFO[0034] Starting ARM Deployment (contoso-apple-59769a59-1423145182). This will take some time...
-INFO[0393] Finished ARM Deployment (contoso-apple-59769a59-1423145182).
+INFO[0034] Starting ARM Deployment (contoso-apple-1423145182). This will take some time...
+INFO[0393] Finished ARM Deployment (contoso-apple-1423145182).
 ```
 
 `acs-engine` will output Azure Resource Manager (ARM) templates, SSH keys, and a kubeconfig file in `_output/contoso-apple-59769a59` directory:
@@ -67,6 +67,8 @@ kubernetes-dashboard is running at https://contoso-apple-59769a59.westus2.clouda
 To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
 ```
 
+Administrative note: By default, the directory where acs-engine stores cluster configuration (`_output/contoso-apple` above) won't be overwritten as a result of subsequent attempts to deploy a cluster using the same `--dns-prefix`) To re-use the same resource group name repeatedly, include the `--force-overwrite` command line option with your `acs-engine deploy` command. On a related note, include an `--auto-suffix` option to append a randomly generated suffix to the dns-prefix to form the resource group name, for example if your workflow requires a common prefix across multiple cluster deployments. Using the `--auto-suffix` pattern appends a compressed timestamp to ensure a unique cluster name (and thus ensure that each deployment's configuration artifacts will be stored locally under a discrete `_output/<resource-group-name>/` directory).
+
 **Note**: If the cluster is using an existing VNET please see the [Custom VNET](features.md#feat-custom-vnet) feature documentation for additional steps that must be completed after cluster provisioning.
 
 <a href="#the-long-way"></a>