Add confirm step

Signed-off-by: Mathieu Frenette <[email protected]>

README.md

@@ -474,7 +474,6 @@ To associate a template with an existing project that was not initially generate
 
 # Wishlist
 
-- Add `confirm` step (similar to `if`, but `confirm` property contains message to display and `then` the steps to execute).
 - Allow `do` step to define multiple actions to call.
 - Add reusable modules (including both templates and scripts).
 - Add support for injecting snippets in specific sections of files in a second time (ie: adding multiple endpoints to an existing service).

examples/templates/hello-world/spec.yaml

@@ -78,6 +78,10 @@ actions:
 
   # By convention, the "uninstall" action is in charge of removing the project from infra
   uninstall:
-    # Here the "exec" step is invoked multiple times, each executing a single command
-    - exec: remove-docker-repo
-    - exec: remove-cicd-triggers
+    # The "confirm" step is similar to "if", however it prompts user with given message and
+    # only upon confirmation executes steps in the "then" clause.
+    - confirm: Are you sure you want to completely uninstall project {{.PROJECT}} from infrastructure?
+      then:
+        # Here the "exec" step is invoked multiple times, each executing a single command
+        - exec: remove-docker-repo
+        - exec: remove-cicd-triggers

src/internal/evaluation/evaluation_test.go

@@ -23,7 +23,7 @@ func (c context) GetPlaceholders() map[string]string {
 	return c.placeholders
 }
 
-func (c context) GetShellVars() []string {
+func (c context) GetShellVars(includeProcessVars bool) []string {
 	vars := make([]string, len(c.vars))
 	for key, value := range c.vars {
 		entry := fmt.Sprintf("%s=%v", key, value)

src/internal/spec/spec.go

@@ -106,13 +106,17 @@ func loadExecutables(list yaml.List, templateDir string) (exec.Executables, erro
 }
 
 func loadExecutable(node yaml.Node, templateDir string) (exec.Executable, error) {
-	// Special case for if step
+	// Special case for if and confirm steps
 	_map, ok := node.(yaml.Map)
 	if ok {
 		_, ok = _map["if"]
 		if ok {
 			return loadIfStep(_map, templateDir)
 		}
+		_, ok = _map["confirm"]
+		if ok {
+			return loadConfirmStep(_map, templateDir)
+		}
 	}
 
 	// Other steps
@@ -186,6 +190,25 @@ func loadIfStep(_map yaml.Map, templateDir string) (exec.Executable, error) {
 	}, nil
 }
 
+func loadConfirmStep(_map yaml.Map, templateDir string) (exec.Executable, error) {
+	message, err := getRequiredStringFromMap(_map, "confirm")
+	if err != nil {
+		return nil, err
+	}
+	list, err := getRequiredList(_map, "then")
+	if err != nil {
+		return nil, err
+	}
+	executables, err := loadExecutables(list, templateDir)
+	if err != nil {
+		return nil, err
+	}
+	return steps.Confirm{
+		Message: message,
+		Then:    executables,
+	}, nil
+}
+
 func loadInputStep(_map yaml.Map, templateDir string) (exec.Executable, error) {
 	question, err := getRequiredStringFromMap(_map, "question")
 	if err != nil {

src/internal/spec/spec_test.go

@@ -73,6 +73,26 @@ then:
 				},
 			},
 		},
+		{
+			Name: "confirm",
+			Buffer: `
+confirm: Message
+then:
+  - input:
+      question: Message
+      var: Variable
+      default: Default`,
+			Expected: steps.Confirm{
+				Message: "Message",
+				Then: exec.Executables{
+					input.Prompt{
+						Message: "Message",
+						Var:     "Variable",
+						Default: "Default",
+					},
+				},
+			},
+		},
 		{
 			Name: "input prompt",
 			Buffer: `

src/internal/steps/confirm.go

@@ -0,0 +1,41 @@
+package steps
+
+import (
+	"github.com/AlecAivazis/survey/v2"
+	"github.com/Samasource/jen/src/internal/evaluation"
+	"github.com/Samasource/jen/src/internal/exec"
+	logging "github.com/Samasource/jen/src/internal/logging"
+)
+
+// Confirm represents a conditional step that executes its child executable only if
+// user answers Yes when prompted for given message
+type Confirm struct {
+	Message string
+	Then    exec.Executables
+}
+
+func (c Confirm) String() string {
+	return "confirm"
+}
+
+// Execute executes a child action only if user answers Yes when prompted for given message
+func (c Confirm) Execute(context exec.Context) error {
+	message, err := evaluation.EvalTemplate(context, c.Message)
+	if err != nil {
+		return err
+	}
+	prompt := &survey.Confirm{
+		Message: message,
+		Default: false,
+	}
+	value := false
+	if err := survey.AskOne(prompt, &value); err != nil {
+		return err
+	}
+	if !value {
+		logging.Log("Skipping sub-steps because user cancelled")
+		return nil
+	}
+	logging.Log("Executing sub-steps because user confirmed")
+	return c.Then.Execute(context)
+}

src/internal/steps/if.go

@@ -16,7 +16,7 @@ type If struct {
 }
 
 func (i If) String() string {
-	return "do"
+	return "if"
 }
 
 // Execute executes a child action only when a given condition evaluates to true

src/internal/steps/input/input.go

@@ -14,6 +14,10 @@ type Prompt struct {
 	Default string
 }
 
+func (p Prompt) String() string {
+	return "input"
+}
+
 // Execute prompts user for input value
 func (p Prompt) Execute(context exec.Context) error {
 	if context.IsVarOverriden(p.Var) {