Add the config array option to the preview command. (#3271)

* Add the config array option to the preview command.

* Update changelog

CHANGELOG.md

@@ -15,6 +15,7 @@ CHANGELOG
   that contain secret values.
   [#3183](https://github.com/pulumi/pulumi/pull/3183)
 - Add Codefresh CI detection.
+- Add `-c` (config array) flag to the `preview` command.
 
 ## 1.1.0 (2019-09-11)
 

cmd/preview.go

@@ -30,6 +30,7 @@ func newPreviewCmd() *cobra.Command {
 	var expectNop bool
 	var message string
 	var stack string
+	var configArray []string
 
 	// Flags for engine.UpdateOptions.
 	var policyPackPaths []string
@@ -93,6 +94,11 @@ func newPreviewCmd() *cobra.Command {
 				return result.FromError(err)
 			}
 
+			// Save any config values passed via flags.
+			if err := parseAndSaveConfigArray(s, configArray); err != nil {
+				return result.FromError(err)
+			}
+
 			proj, root, err := readProject(pulumiAppProj)
 			if err != nil {
 				return result.FromError(err)
@@ -146,6 +152,9 @@ func newPreviewCmd() *cobra.Command {
 	cmd.PersistentFlags().StringVar(
 		&stackConfigFile, "config-file", "",
 		"Use the configuration values in the specified file rather than detecting the file name")
+	cmd.PersistentFlags().StringArrayVarP(
+		&configArray, "config", "c", []string{},
+		"Config to use during the preview")
 
 	cmd.PersistentFlags().StringVarP(
 		&message, "message", "m", "",

cmd/up.go

@@ -74,15 +74,8 @@ func newUpCmd() *cobra.Command {
 		}
 
 		// Save any config values passed via flags.
-		if len(configArray) > 0 {
-			commandLineConfig, err := parseConfig(configArray)
-			if err != nil {
-				return result.FromError(err)
-			}
-
-			if err = saveConfig(s, commandLineConfig); err != nil {
-				return result.FromError(errors.Wrap(err, "saving config"))
-			}
+		if err := parseAndSaveConfigArray(s, configArray); err != nil {
+			return result.FromError(err)
 		}
 
 		proj, root, err := readProject(pulumiAppProj)

cmd/util.go

@@ -324,6 +324,23 @@ const (
 	pulumiPolicyProj projType = "pulumi-policy"
 )
 
+// parseAndSaveConfigArray parses the config array and saves it as a config for
+// the provided stack.
+func parseAndSaveConfigArray(s backend.Stack, configArray []string) error {
+	if len(configArray) == 0 {
+		return nil
+	}
+	commandLineConfig, err := parseConfig(configArray)
+	if err != nil {
+		return err
+	}
+
+	if err = saveConfig(s, commandLineConfig); err != nil {
+		return errors.Wrap(err, "saving config")
+	}
+	return nil
+}
+
 // readProject attempts to detect and read a project of type `projType` for the current workspace.
 // If the project is successfully detected and read, it is returned along with the path to its
 // containing directory, which will be used as the root of the project's Pulumi program.