Rework of CLI flag remapping

CHANGELOG.md

@@ -1,13 +1,27 @@
 # astro changelog
 
-## 0.4.2 (UNRELEASED, 2018)
+## 0.5.0 (UNRELEASED, 2018)
 
 * Add Travis configuration, `make lint` and git precommit hook
+* Fix `--help` displaying "pflag: help requested" (#1)
 * Fix issue with make not recompiling when source files changed
 * Fix issue with `make test` always returning true even when tests fail
 * Fix race condition that could cause failures due to astro downloading the
   same version of Terraform twice
 * Remove godep and move to Go modules (vgo)
+* Change configuration syntax for remapping CLI flags to Terraform module
+  variables
+
+**Breaking changes:**
+
+* Before, there was a `flag:` option underneath module variables in the project
+  configuration that allowed you to modify the name of the flag on the CLI that
+  would represent that variable (e.g.: "--environment" could be remapped to
+  "--env").
+
+  This has been removed and there is now a completely new section in the YAML
+  called "flags". See the "Remapping flags" section of the README for more
+  information.
 
 ## 0.4.1 (October 3, 2018)
 

README.md

@@ -228,3 +228,18 @@ database-dev-us-east-1: OK No changes (9s)
 app-dev-us-east-1: OK No changes (10s)
 >
 ```
+
+#### Remapping CLI flags
+
+Astro is meant to be used every day by operators. If your Terraform variable names are long-winded to type at the CLI, you can remap them to something simpler. For example, instead of typing `--environment dev`, you may wish to shoren this to `--env dev`.
+
+You can specify a `flags:` block in your project configuration, like:
+
+```
+flags:
+  environment:
+    name: env
+    description: Environment to deploy to
+```
+
+This will remap the "environment" Terraform variable to `--env` on the astro command line. You can also specify a description that will show up in the `--help` text.

astro/cli/astro/cmd/cmd_test.go

@@ -56,6 +56,8 @@ var (
 	terraformVersionRepo *tvm.VersionRepo
 )
 
+const VERSION_LATEST = ""
+
 // compiles the astro binary and returns the path to it.
 func compileAstro() (string, error) {
 	f, err := ioutil.TempFile("", "")
@@ -109,6 +111,10 @@ type testResult struct {
 func runTest(t *testing.T, args []string, fixtureBasePath string, version string) *testResult {
 	fixturePath := fixtureBasePath
 
+	if version == VERSION_LATEST {
+		version = terraformVersionsToTest[len(terraformVersionsToTest)-1]
+	}
+
 	// Determine if this version has a version-specific fixture.
 	versionSpecificFixturePath := fmt.Sprintf("%s-%s", fixtureBasePath, version)
 	if utils.FileExists(versionSpecificFixturePath) {
@@ -184,6 +190,12 @@ func getSessionDirs(sessionBaseDir string) ([]string, error) {
 	return sessionDirs, nil
 }
 
+func TestHelpWorks(t *testing.T) {
+	result := runTest(t, []string{"--help"}, "", VERSION_LATEST)
+	assert.Contains(t, "A tool for managing multiple Terraform modules", result.Stderr.String())
+	assert.NoError(t, result.Err)
+}
+
 func TestProjectApplyChangesSuccess(t *testing.T) {
 	for _, version := range terraformVersionsToTest {
 		t.Run(version, func(t *testing.T) {

astro/cli/astro/cmd/cmds.go

@@ -40,7 +40,7 @@ var applyCmd = &cobra.Command{
 			return err
 		}
 
-		vars := userVariables()
+		vars := flagsToUserVariables()
 
 		var moduleNames []string
 		if moduleNamesString != "" {
@@ -57,7 +57,7 @@ var applyCmd = &cobra.Command{
 			},
 		)
 		if err != nil {
-			return fmt.Errorf("error running Terraform: %v", err)
+			return fmt.Errorf("ERROR: %v", processError(err))
 		}
 
 		err = printExecStatus(status, results)
@@ -81,7 +81,7 @@ var planCmd = &cobra.Command{
 			return err
 		}
 
-		vars := userVariables()
+		vars := flagsToUserVariables()
 
 		var moduleNames []string
 		if moduleNamesString != "" {
@@ -99,7 +99,7 @@ var planCmd = &cobra.Command{
 			},
 		)
 		if err != nil {
-			return fmt.Errorf("error running Terraform: %v", err)
+			return fmt.Errorf("ERROR: %v", processError(err))
 		}
 
 		err = printExecStatus(status, results)
@@ -113,25 +113,6 @@ var planCmd = &cobra.Command{
 	},
 }
 
-func userVariables() *astro.UserVariables {
-	values := make(map[string]string)
-	filters := make(map[string]bool)
-
-	for _, flag := range _flags {
-		if flag.Value != "" {
-			values[flag.Variable] = flag.Value
-			if flag.IsFilter {
-				filters[flag.Variable] = true
-			}
-		}
-	}
-
-	return &astro.UserVariables{
-		Values:  values,
-		Filters: filters,
-	}
-}
-
 func init() {
 	applyCmd.PersistentFlags().StringVar(&moduleNamesString, "modules", "", "list of modules to apply")
 	rootCmd.AddCommand(applyCmd)
@@ -140,3 +121,15 @@ func init() {
 	planCmd.PersistentFlags().StringVar(&moduleNamesString, "modules", "", "list of modules to plan")
 	rootCmd.AddCommand(planCmd)
 }
+
+// processError interprets certain astro errors and embellishes them for
+// display on the CLI.
+func processError(err error) error {
+	switch e := err.(type) {
+	case astro.MissingRequiredVarsError:
+		// reverse map variables to CLI flags
+		return fmt.Errorf("missing required flags: %s", strings.Join(varsToFlagNames(e.MissingVars()), ", "))
+	default:
+		return err
+	}
+}

astro/cli/astro/cmd/config.go

@@ -16,7 +16,14 @@
 
 package cmd
 
-import "github.com/uber/astro/astro/utils"
+import (
+	"errors"
+	"fmt"
+
+	"github.com/uber/astro/astro"
+	"github.com/uber/astro/astro/conf"
+	"github.com/uber/astro/astro/utils"
+)
 
 // configFileSearchPaths is the default list of paths the astro CLI
 // will attempt to find a config file at.
@@ -27,6 +34,14 @@ var configFileSearchPaths = []string{
 	"terraform/astro.yml",
 }
 
+var errCannotFindConfig = errors.New("unable to find config file")
+
+// Global cache
+var (
+	_conf    *conf.Project
+	_project *astro.Project
+)
+
 // firstExistingFilePath takes a list of paths and returns the first one
 // where a file exists (or symlink to a file).
 func firstExistingFilePath(paths ...string) string {
@@ -37,3 +52,54 @@ func firstExistingFilePath(paths ...string) string {
 	}
 	return ""
 }
+
+// configFile returns the path of the project config file.
+func configFile() (string, error) {
+	// User provided config file path takes precedence
+	if userCfgFile != "" {
+		return userCfgFile, nil
+	}
+
+	// Try to find the config file
+	if path := firstExistingFilePath(configFileSearchPaths...); path != "" {
+		return path, nil
+	}
+
+	return "", errCannotFindConfig
+}
+
+// currentConfig loads configuration or returns the previously loaded config.
+func currentConfig() (*conf.Project, error) {
+	if _conf != nil {
+		return _conf, nil
+	}
+
+	file, err := configFile()
+	if err != nil {
+		return nil, err
+	}
+	_conf, err = astro.NewConfigFromFile(file)
+
+	return _conf, err
+}
+
+// currentProject creates a new astro project or returns the previously created
+// astro project.
+func currentProject() (*astro.Project, error) {
+	if _project != nil {
+		return _project, nil
+	}
+
+	config, err := currentConfig()
+	if err != nil {
+		return nil, err
+	}
+	c, err := astro.NewProject(*config)
+	if err != nil {
+		return nil, fmt.Errorf("unable to load module configuration: %v", err)
+	}
+
+	_project = c
+
+	return _project, nil
+}

astro/cli/astro/cmd/fixtures/flags/merge_values.yaml

@@ -1,7 +1,7 @@
 ---
 
 terraform:
-  version: 0.11.7
+  path: ../../../../../fixtures/mock-terraform/success
 
 modules:
   - name: foo_mgmt

astro/cli/astro/cmd/fixtures/flags/no_variables.yaml

@@ -1,7 +1,7 @@
 ---
 
 terraform:
-  version: 0.11.7
+  path: ../../../../../fixtures/mock-terraform/success
 
 modules:
   - name: foo

astro/cli/astro/cmd/fixtures/flags/simple_variables.yaml

@@ -1,14 +1,18 @@
 ---
 
 terraform:
-  version: 0.11.7
+  path: ../../../../../fixtures/mock-terraform/success
+
+flags:
+  bar:
+    name: baz
+    description: Baz Description
 
 modules:
-  - name: foo
+  - name: fooModule
     path: .
     variables:
-      - name: no_flag
-      - name: with_flag
-        flag: flag_name
-      - name: with_values
+      - name: foo
+      - name: bar
+      - name: qux
         values: [dev, staging, prod]