Allow themes to define output formats, media types and params

Fixes gohugoio#4490

hugolib/config.go

@@ -16,6 +16,7 @@ package hugolib
 import (
 	"errors"
 	"fmt"
+	"path/filepath"
 
 	"io"
 	"strings"
@@ -85,7 +86,8 @@ func LoadConfig(d ConfigSourceDescriptor) (*viper.Viper, error) {
 		return v, err
 	}
 
-	return v, nil
+	return v, loadThemeConfig(fs, v)
+
 }
 
 func loadLanguageSettings(cfg config.Provider, oldLangs helpers.Languages) error {
@@ -201,6 +203,77 @@ func loadLanguageSettings(cfg config.Provider, oldLangs helpers.Languages) error
 	return nil
 }
 
+func loadThemeConfig(fs afero.Fs, v1 *viper.Viper) error {
+
+	theme := v1.GetString("theme")
+	if theme == "" {
+		return nil
+	}
+
+	themesDir := v1.GetString("themesDir")
+	configDir := filepath.Join(themesDir, theme)
+
+	var configPath string
+	var exists bool
+	var err error
+
+	for _, exensionsToCheck := range []string{"toml", "yaml", "yml", "json"} {
+		configPath = filepath.Join(configDir, "config."+exensionsToCheck)
+		exists, err = helpers.Exists(configPath, fs)
+		if err != nil {
+			return err
+		}
+		if exists {
+			break
+		}
+	}
+
+	if !exists {
+		return nil
+	}
+
+	v2 := viper.New()
+	v2.SetFs(fs)
+	v2.AutomaticEnv()
+	v2.SetEnvPrefix("hugo")
+	v2.SetConfigFile(configPath)
+
+	err = v2.ReadInConfig()
+	if err != nil {
+		return err
+	}
+
+	for _, key := range []string{"params", "outputformats", "mediatypes"} {
+		mergeStringMapKeepLeft(key, v1, v2)
+	}
+
+	return nil
+
+}
+
+func mergeStringMapKeepLeft(key string, v1, v2 *viper.Viper) {
+	if !v1.IsSet(key) {
+		if v2.IsSet(key) {
+			v1.Set(key, v2.Get(key))
+		}
+		return
+	}
+
+	if !v2.IsSet(key) {
+		return
+	}
+
+	m1 := v1.GetStringMap(key)
+	m2 := v2.GetStringMap(key)
+
+	for k, v := range m2 {
+		if _, found := m1[k]; !found {
+			m1[k] = v
+		}
+	}
+
+}
+
 func loadDefaultSettingsFor(v *viper.Viper) error {
 
 	c, err := helpers.NewContentSpec(v)
@@ -282,4 +355,5 @@ lastmod = ["lastmod" ,":fileModTime", ":default"]
 	}
 
 	return loadLanguageSettings(v, nil)
+
 }

hugolib/config_test.go

@@ -14,16 +14,20 @@
 package hugolib
 
 import (
+	"fmt"
 	"testing"
 
+	"github.com/spf13/viper"
+
 	"github.com/spf13/afero"
-	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
 func TestLoadConfig(t *testing.T) {
 	t.Parallel()
 
+	assert := require.New(t)
+
 	// Add a random config variable for testing.
 	// side = page in Norwegian.
 	configContent := `
@@ -37,13 +41,16 @@ func TestLoadConfig(t *testing.T) {
 	cfg, err := LoadConfig(ConfigSourceDescriptor{Fs: mm, Name: "hugo.toml"})
 	require.NoError(t, err)
 
-	assert.Equal(t, "side", cfg.GetString("paginatePath"))
+	assert.Equal("side", cfg.GetString("paginatePath"))
 	// default
-	assert.Equal(t, "layouts", cfg.GetString("layoutDir"))
+	assert.Equal("layouts", cfg.GetString("layoutDir"))
 }
+
 func TestLoadMultiConfig(t *testing.T) {
 	t.Parallel()
 
+	assert := require.New(t)
+
 	// Add a random config variable for testing.
 	// side = page in Norwegian.
 	configContentBase := `
@@ -62,6 +69,82 @@ func TestLoadMultiConfig(t *testing.T) {
 	cfg, err := LoadConfig(ConfigSourceDescriptor{Fs: mm, Name: "base.toml,override.toml"})
 	require.NoError(t, err)
 
-	assert.Equal(t, "top", cfg.GetString("paginatePath"))
-	assert.Equal(t, "same", cfg.GetString("DontChange"))
+	assert.Equal("top", cfg.GetString("paginatePath"))
+	assert.Equal("same", cfg.GetString("DontChange"))
+}
+
+func TestLoadConfigFromTheme(t *testing.T) {
+	t.Parallel()
+
+	assert := require.New(t)
+
+	mainConfig := `
+theme = "test-theme"
+baseURL = "https://example.com/"
+
+[frontmatter]
+date = ["date","publishDate"]
+
+[params]
+p1 = "p1 main"
+p2 = "p2 main"
+
+[mediaTypes]
+[mediaTypes."text/m1"]
+suffix = "m1main"
+
+[outputFormats.o1]
+mediaType = "text/m1"
+baseName = "o1main"
+`
+
+	themeConfig := `
+baseURL = "http://bep.is/"
+
+# Can not be set in theme.
+[frontmatter]
+expiryDate = ["date"]
+
+[params]
+p1 = "p1 theme"
+p2 = "p2 theme"
+p3 = "p3 theme"
+
+[mediaTypes]
+[mediaTypes."text/m1"]
+suffix = "m1theme"
+[mediaTypes."text/m2"]
+suffix = "m2theme"
+
+[outputFormats.o1]
+mediaType = "text/m1"
+baseName = "o1theme"
+[outputFormats.o2]
+mediaType = "text/m1"
+baseName = "o2theme"
+`
+
+	b := newTestSitesBuilder(t)
+	b.WithConfigFile("toml", mainConfig).WithThemeConfigFile("toml", themeConfig)
+	b.CreateSites().Build(BuildCfg{})
+
+	expected := map[string]interface{}{
+		"baseurl": "http://bep.is/",
+		"frontmatter": map[string]interface{}{
+			"date": []interface{}{"date", "publishDate"},
+		},
+		"params": map[string]interface{}{
+			"p1": "p1 main",
+			"p2": "p2 main",
+			"p3": "p3 theme",
+		},
+	}
+
+	got := b.Cfg.(*viper.Viper).AllSettings()
+
+	assert.Equal(expected["params"], got["params"])
+	assert.Equal(expected["frontmatter"], got["frontmatter"])
+
+	fmt.Println(">", expected, "\ngot", got)
+
 }

hugolib/site.go

@@ -296,6 +296,7 @@ func NewSite(cfg deps.DepsCfg) (*Site, error) {
 // NewSiteDefaultLang creates a new site in the default language.
 // The site will have a template system loaded and ready to use.
 // Note: This is mainly used in single site tests.
+// TODO(bep) test refactor -- remove
 func NewSiteDefaultLang(withTemplate ...func(templ tpl.TemplateHandler) error) (*Site, error) {
 	v := viper.New()
 	if err := loadDefaultSettingsFor(v); err != nil {
@@ -307,6 +308,7 @@ func NewSiteDefaultLang(withTemplate ...func(templ tpl.TemplateHandler) error) (
 // NewEnglishSite creates a new site in English language.
 // The site will have a template system loaded and ready to use.
 // Note: This is mainly used in single site tests.
+// TODO(bep) test refactor -- remove
 func NewEnglishSite(withTemplate ...func(templ tpl.TemplateHandler) error) (*Site, error) {
 	v := viper.New()
 	if err := loadDefaultSettingsFor(v); err != nil {

hugolib/testhelpers_test.go

@@ -42,6 +42,8 @@ type sitesBuilder struct {
 
 	H *HugoSites
 
+	theme string
+
 	// Default toml
 	configFormat string
 
@@ -97,6 +99,15 @@ func (s *sitesBuilder) WithConfigFile(format, conf string) *sitesBuilder {
 	return s
 }
 
+func (s *sitesBuilder) WithThemeConfigFile(format, conf string) *sitesBuilder {
+	if s.theme == "" {
+		s.theme = "test-theme"
+	}
+	filename := filepath.Join("themes", s.theme, "config."+format)
+	writeSource(s.T, s.Fs, filename, conf)
+	return s
+}
+
 func (s *sitesBuilder) WithSimpleConfigFile() *sitesBuilder {
 	var config = `
 baseURL = "http://example.com/"