feat: support templates in initHelp

Author: majori

cmd/docs/templates/_schema.tmpl

@@ -11,7 +11,7 @@
 | `description` | `string` | | Description of what the recipe does |
 | `source` | `string` | | URL to source code for this recipe. |
 | `templateExtension` | `string` | | File extension of files in "templates" directory which should be templated. Files not matched by this extension will be copied as-is. If left empty (the default), all files will be templated. |
-| `initHelp` | `string` | | A message which will be showed to an user after a succesful recipe execution. Can be used to guide the user what should be done next in the project directory. |
+| `initHelp` | `string` | | A message which will be showed to an user after a succesful recipe execution. Can be used to guide the user what should be done next in the project directory. Supports templating |
 | `ignorePatterns` | `[]string` | | Glob patterns for ignoring generated files from future recipe upgrades. Ignored files will not be regenerated even if their templates change in future versions of the recipe. |
 | `vars` | [`[]Variable`](#variable) | | An array of variables which can be used in templates. The user will be prompted to provide the value for the variable if not set with `--set` flag. |
 

go.mod

@@ -35,6 +35,7 @@ require (
 	github.com/cucumber/messages/go/v21 v21.0.1 // indirect
 	github.com/docker/docker v24.0.6+incompatible // indirect
 	github.com/docker/docker-credential-helpers v0.8.0 // indirect
+	github.com/fatih/structs v1.1.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect

go.sum

@@ -59,6 +59,8 @@ github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4
 github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
 github.com/expr-lang/expr v1.16.0 h1:BQabx+PbjsL2PEQwkJ4GIn3CcuUh8flduHhJ0lHjWwE=
 github.com/expr-lang/expr v1.16.0/go.mod h1:uCkhfG+x7fcZ5A5sXHKuQ07jGZRl6J0FCAaf2k4PtVQ=
+github.com/fatih/structs v1.1.0 h1:Q7juDM0QtcnhCpeyLGQKyg4TOIghuNXrkL32pHAUMxo=
+github.com/fatih/structs v1.1.0/go.mod h1:9NiDSp5zOcgEDl+j00MP/WkGVPOlPRLejGD8Ga6PJ7M=
 github.com/go-sql-driver/mysql v1.6.0 h1:BCTh4TKNUYmOmMUcQ3IipzF5prigylS7XXjEkfCHuOE=
 github.com/go-sql-driver/mysql v1.6.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
 github.com/gofrs/uuid v4.2.0+incompatible/go.mod h1:b2aQJv3Z4Fp6yNu3cdSllBxTCLRxnplIgP/c0N/04lM=

internal/cli/execute.go

@@ -208,7 +208,11 @@ func runExecute(cmd *cobra.Command, opts executeOptions) error {
 	cmd.Printf("The following files were created:\n\n%s", tree)
 
 	if re.InitHelp != "" {
-		cmd.Printf("\nNext up: %s\n", re.InitHelp)
+		help, err := sauce.RenderInitHelp()
+		if err != nil {
+			return err
+		}
+		cmd.Printf("\nNext up: %s\n", help)
 	}
 
 	return nil

pkg/recipe/execute.go

@@ -9,6 +9,18 @@ import (
 	"github.com/gofrs/uuid"
 )
 
+// TemplateContext defines the context that is passed to the template engine
+type TemplateContext struct {
+	ID     string
+	Recipe struct {
+		APIVersion string
+		Name       string
+		Version    string
+		Source     string
+	}
+	Variables VariableValues
+}
+
 type RenderEngine interface {
 	Render(templates map[string][]byte, values map[string]interface{}) (map[string][]byte, error)
 }
@@ -23,29 +35,9 @@ func (re *Recipe) Execute(engine RenderEngine, values VariableValues, id uuid.UU
 	sauce.Recipe = *re
 	sauce.Values = values
 	sauce.ID = id
+	sauce.Files = make(map[string]File, len(re.Templates))
 
-	mappedValues := make(VariableValues)
-	for name, value := range values {
-		switch value := value.(type) {
-		// Map table to more convenient format
-		case TableValue:
-			mappedValues[name] = value.ToMapSlice()
-		default:
-			mappedValues[name] = value
-		}
-	}
-
-	// Define the context which is available on templates
-	context := map[string]interface{}{
-		"ID": sauce.ID.String(),
-		"Recipe": struct{ APIVersion, Name, Version, Source string }{
-			re.APIVersion,
-			re.Name,
-			re.Version,
-			re.Source,
-		},
-		"Variables": mappedValues,
-	}
+	context := sauce.CreateTemplateContext()
 
 	// Filter out templates we might not want to render
 	templates := make(map[string][]byte)
@@ -66,8 +58,6 @@ func (re *Recipe) Execute(engine RenderEngine, values VariableValues, id uuid.UU
 	// Add the plain files
 	maps.Copy(files, plainFiles)
 
-	sauce.Files = make(map[string]File, len(re.Templates))
-
 	idx := 0
 	for filename, content := range files {
 		// Skip empty files

pkg/recipe/sauce.go

@@ -2,7 +2,10 @@ package recipe
 
 import (
 	"fmt"
+	"strings"
+	"text/template"
 
+	"github.com/fatih/structs"
 	"github.com/gofrs/uuid"
 )
 
@@ -82,3 +85,42 @@ func (s *Sauce) Conflicts(other *Sauce) []RecipeConflict {
 	}
 	return conflicts
 }
+
+func (s *Sauce) CreateTemplateContext() map[string]interface{} {
+	mappedValues := make(VariableValues)
+	for name, value := range s.Values {
+		switch value := value.(type) {
+		// Map table to more convenient format
+		case TableValue:
+			mappedValues[name] = value.ToMapSlice()
+		default:
+			mappedValues[name] = value
+		}
+	}
+
+	return structs.Map(TemplateContext{
+		ID: s.ID.String(),
+		Recipe: struct{ APIVersion, Name, Version, Source string }{
+			s.Recipe.APIVersion,
+			s.Recipe.Name,
+			s.Recipe.Version,
+			s.Recipe.Source,
+		},
+		Variables: mappedValues,
+	})
+}
+
+func (s *Sauce) RenderInitHelp() (string, error) {
+	context := s.CreateTemplateContext()
+	t, err := template.New("initHelp").Parse(s.Recipe.InitHelp)
+	if err != nil {
+		return "", fmt.Errorf("failed to parse initHelp template: %w", err)
+	}
+
+	var buf strings.Builder
+	if err := t.Execute(&buf, context); err != nil {
+		return "", fmt.Errorf("failed to render initHelp template: %w", err)
+	}
+
+	return buf.String(), nil
+}

pkg/recipe/sauce_test.go

@@ -0,0 +1,61 @@
+package recipe
+
+import (
+	"testing"
+
+	"github.com/gofrs/uuid"
+)
+
+func TestRenderInitHelp(t *testing.T) {
+	scenarios := []struct {
+		name           string
+		help           string
+		values         VariableValues
+		expectedOutput string
+		expectingErr   bool
+	}{
+		{
+			"conditional text",
+			"{{ if .Variables.FOO }}Foo is true{{ else }}Foo is false{{ end }}",
+			VariableValues{
+				"FOO": true,
+			},
+			"Foo is true",
+			false,
+		},
+		{
+			"invalid template",
+			"{{ if .Variables.NOT_FOUND }}",
+			VariableValues{
+				"FOO": true,
+			},
+			"",
+			true,
+		},
+	}
+
+	for _, scenario := range scenarios {
+		t.Run(scenario.name, func(t *testing.T) {
+			re := NewRecipe()
+			re.Name = "test"
+			re.Version = "0.0.0"
+			re.InitHelp = scenario.help
+
+			sauce := NewSauce()
+			sauce.Recipe = *re
+			sauce.ID = uuid.Must(uuid.NewV4())
+			sauce.Values = scenario.values
+
+			if help, err := sauce.RenderInitHelp(); err != nil {
+				if !scenario.expectingErr {
+					t.Fatalf("Got error when not expected: %s", err)
+				}
+			} else if scenario.expectingErr {
+				t.Fatal("Was expecting error, did not get any")
+
+			} else if help != scenario.expectedOutput {
+				t.Fatalf("Expected output '%s', got '%s'", scenario.expectedOutput, help)
+			}
+		})
+	}
+}