hugo/hugolib/config.go
Bjørn Erik Pedersen 80230f26a3
Add support for theme composition and inheritance
This commit adds support for theme composition and inheritance in Hugo.

With this, it helps thinking about a theme as a set of ordered components:

```toml
theme = ["my-shortcodes", "base-theme", "hyde"]
```

The theme definition example above in `config.toml` creates a theme with the 3 components with presedence from left to right.

So, Hugo will, for any given file, data entry etc., look first in the project, and then in `my-shortcode`, `base-theme` and lastly `hyde`.

Hugo uses two different algorithms to merge the filesystems, depending on the file type:

* For `i18n` and `data` files, Hugo merges deeply using the translation id and data key inside the files.
* For `static`, `layouts` (templates) and `archetypes` files, these are merged on file level. So the left-most file will be chosen.

The name used in the `theme` definition above must match a folder in `/your-site/themes`, e.g. `/your-site/themes/my-shortcodes`. There are  plans to improve on this and get a URL scheme so this can be resolved automatically.

Also note that a component that is part of a theme can have its own configuration file, e.g. `config.toml`. There are currently some restrictions to what a theme component can configure:

* `params` (global and per language)
* `menu` (global and per language)
* `outputformats` and `mediatypes`

The same rules apply here: The left-most param/menu etc. with the same ID will win. There are some hidden and experimental namespace support in the above, which we will work to improve in the future, but theme authors are encouraged to create their own namespaces to avoid naming conflicts.

A final note: Themes/components can also have a `theme` definition in their `config.toml` and similar, which is the "inheritance" part of this commit's title. This is currently not supported by the Hugo theme site. We will have to wait for some "auto dependency" feature to be implemented for that to happen, but this can be a powerful feature if you want to create your own theme-variant based on others.

Fixes #4460
Fixes #4450
2018-06-10 23:55:20 +02:00

482 lines
13 KiB
Go

// Copyright 2016-present The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package hugolib
import (
"errors"
"fmt"
"github.com/gohugoio/hugo/hugolib/paths"
"io"
"strings"
"github.com/gohugoio/hugo/langs"
"github.com/gohugoio/hugo/config"
"github.com/gohugoio/hugo/config/privacy"
"github.com/gohugoio/hugo/config/services"
"github.com/gohugoio/hugo/helpers"
"github.com/spf13/afero"
"github.com/spf13/viper"
)
// SiteConfig represents the config in .Site.Config.
type SiteConfig struct {
// This contains all privacy related settings that can be used to
// make the YouTube template etc. GDPR compliant.
Privacy privacy.Config
// Services contains config for services such as Google Analytics etc.
Services services.Config
}
func loadSiteConfig(cfg config.Provider) (scfg SiteConfig, err error) {
privacyConfig, err := privacy.DecodeConfig(cfg)
if err != nil {
return
}
servicesConfig, err := services.DecodeConfig(cfg)
if err != nil {
return
}
scfg.Privacy = privacyConfig
scfg.Services = servicesConfig
return
}
// ConfigSourceDescriptor describes where to find the config (e.g. config.toml etc.).
type ConfigSourceDescriptor struct {
Fs afero.Fs
// Full path to the config file to use, i.e. /my/project/config.toml
Filename string
// The path to the directory to look for configuration. Is used if Filename is not
// set.
Path string
// The project's working dir. Is used to look for additional theme config.
WorkingDir string
}
func (d ConfigSourceDescriptor) configFilenames() []string {
return strings.Split(d.Filename, ",")
}
// LoadConfigDefault is a convenience method to load the default "config.toml" config.
func LoadConfigDefault(fs afero.Fs) (*viper.Viper, error) {
v, _, err := LoadConfig(ConfigSourceDescriptor{Fs: fs, Filename: "config.toml"})
return v, err
}
var ErrNoConfigFile = errors.New("Unable to locate Config file. Perhaps you need to create a new site.\n Run `hugo help new` for details.\n")
// LoadConfig loads Hugo configuration into a new Viper and then adds
// a set of defaults.
func LoadConfig(d ConfigSourceDescriptor, doWithConfig ...func(cfg config.Provider) error) (*viper.Viper, []string, error) {
var configFiles []string
fs := d.Fs
v := viper.New()
v.SetFs(fs)
if d.Path == "" {
d.Path = "."
}
configFilenames := d.configFilenames()
v.AutomaticEnv()
v.SetEnvPrefix("hugo")
v.SetConfigFile(configFilenames[0])
v.AddConfigPath(d.Path)
var configFileErr error
err := v.ReadInConfig()
if err != nil {
if _, ok := err.(viper.ConfigParseError); ok {
return nil, configFiles, err
}
configFileErr = ErrNoConfigFile
}
if configFileErr == nil {
if cf := v.ConfigFileUsed(); cf != "" {
configFiles = append(configFiles, cf)
}
for _, configFile := range configFilenames[1:] {
var r io.Reader
var err error
if r, err = fs.Open(configFile); err != nil {
return nil, configFiles, fmt.Errorf("Unable to open Config file.\n (%s)\n", err)
}
if err = v.MergeConfig(r); err != nil {
return nil, configFiles, fmt.Errorf("Unable to parse/merge Config file (%s).\n (%s)\n", configFile, err)
}
configFiles = append(configFiles, configFile)
}
}
if err := loadDefaultSettingsFor(v); err != nil {
return v, configFiles, err
}
if configFileErr == nil {
themeConfigFiles, err := loadThemeConfig(d, v)
if err != nil {
return v, configFiles, err
}
if len(themeConfigFiles) > 0 {
configFiles = append(configFiles, themeConfigFiles...)
}
}
// We create languages based on the settings, so we need to make sure that
// all configuration is loaded/set before doing that.
for _, d := range doWithConfig {
if err := d(v); err != nil {
return v, configFiles, err
}
}
if err := loadLanguageSettings(v, nil); err != nil {
return v, configFiles, err
}
return v, configFiles, configFileErr
}
func loadLanguageSettings(cfg config.Provider, oldLangs langs.Languages) error {
defaultLang := cfg.GetString("defaultContentLanguage")
var languages map[string]interface{}
languagesFromConfig := cfg.GetStringMap("languages")
disableLanguages := cfg.GetStringSlice("disableLanguages")
if len(disableLanguages) == 0 {
languages = languagesFromConfig
} else {
languages = make(map[string]interface{})
for k, v := range languagesFromConfig {
for _, disabled := range disableLanguages {
if disabled == defaultLang {
return fmt.Errorf("cannot disable default language %q", defaultLang)
}
if strings.EqualFold(k, disabled) {
v.(map[string]interface{})["disabled"] = true
break
}
}
languages[k] = v
}
}
var (
languages2 langs.Languages
err error
)
if len(languages) == 0 {
languages2 = append(languages2, langs.NewDefaultLanguage(cfg))
} else {
languages2, err = toSortedLanguages(cfg, languages)
if err != nil {
return fmt.Errorf("Failed to parse multilingual config: %s", err)
}
}
if oldLangs != nil {
// When in multihost mode, the languages are mapped to a server, so
// some structural language changes will need a restart of the dev server.
// The validation below isn't complete, but should cover the most
// important cases.
var invalid bool
if languages2.IsMultihost() != oldLangs.IsMultihost() {
invalid = true
} else {
if languages2.IsMultihost() && len(languages2) != len(oldLangs) {
invalid = true
}
}
if invalid {
return errors.New("language change needing a server restart detected")
}
if languages2.IsMultihost() {
// We need to transfer any server baseURL to the new language
for i, ol := range oldLangs {
nl := languages2[i]
nl.Set("baseURL", ol.GetString("baseURL"))
}
}
}
// The defaultContentLanguage is something the user has to decide, but it needs
// to match a language in the language definition list.
langExists := false
for _, lang := range languages2 {
if lang.Lang == defaultLang {
langExists = true
break
}
}
if !langExists {
return fmt.Errorf("site config value %q for defaultContentLanguage does not match any language definition", defaultLang)
}
cfg.Set("languagesSorted", languages2)
cfg.Set("multilingual", len(languages2) > 1)
multihost := languages2.IsMultihost()
if multihost {
cfg.Set("defaultContentLanguageInSubdir", true)
cfg.Set("multihost", true)
}
if multihost {
// The baseURL may be provided at the language level. If that is true,
// then every language must have a baseURL. In this case we always render
// to a language sub folder, which is then stripped from all the Permalink URLs etc.
for _, l := range languages2 {
burl := l.GetLocal("baseURL")
if burl == nil {
return errors.New("baseURL must be set on all or none of the languages")
}
}
}
return nil
}
func loadThemeConfig(d ConfigSourceDescriptor, v1 *viper.Viper) ([]string, error) {
themesDir := paths.AbsPathify(d.WorkingDir, v1.GetString("themesDir"))
themes := config.GetStringSlicePreserveString(v1, "theme")
// CollectThemes(fs afero.Fs, themesDir string, themes []strin
themeConfigs, err := paths.CollectThemes(d.Fs, themesDir, themes)
if err != nil {
return nil, err
}
v1.Set("allThemes", themeConfigs)
var configFilenames []string
for _, tc := range themeConfigs {
if tc.ConfigFilename != "" {
configFilenames = append(configFilenames, tc.ConfigFilename)
if err := applyThemeConfig(v1, tc); err != nil {
return nil, err
}
}
}
return configFilenames, nil
}
func applyThemeConfig(v1 *viper.Viper, theme paths.ThemeConfig) error {
const (
paramsKey = "params"
languagesKey = "languages"
menuKey = "menu"
)
v2 := theme.Cfg
for _, key := range []string{paramsKey, "outputformats", "mediatypes"} {
mergeStringMapKeepLeft("", key, v1, v2)
}
themeLower := strings.ToLower(theme.Name)
themeParamsNamespace := paramsKey + "." + themeLower
// Set namespaced params
if v2.IsSet(paramsKey) && !v1.IsSet(themeParamsNamespace) {
// Set it in the default store to make sure it gets in the same or
// behind the others.
v1.SetDefault(themeParamsNamespace, v2.Get(paramsKey))
}
// Only add params and new menu entries, we do not add language definitions.
if v1.IsSet(languagesKey) && v2.IsSet(languagesKey) {
v1Langs := v1.GetStringMap(languagesKey)
for k, _ := range v1Langs {
langParamsKey := languagesKey + "." + k + "." + paramsKey
mergeStringMapKeepLeft(paramsKey, langParamsKey, v1, v2)
}
v2Langs := v2.GetStringMap(languagesKey)
for k, _ := range v2Langs {
if k == "" {
continue
}
langParamsKey := languagesKey + "." + k + "." + paramsKey
langParamsThemeNamespace := langParamsKey + "." + themeLower
// Set namespaced params
if v2.IsSet(langParamsKey) && !v1.IsSet(langParamsThemeNamespace) {
v1.SetDefault(langParamsThemeNamespace, v2.Get(langParamsKey))
}
langMenuKey := languagesKey + "." + k + "." + menuKey
if v2.IsSet(langMenuKey) {
// Only add if not in the main config.
v2menus := v2.GetStringMap(langMenuKey)
for k, v := range v2menus {
menuEntry := menuKey + "." + k
menuLangEntry := langMenuKey + "." + k
if !v1.IsSet(menuEntry) && !v1.IsSet(menuLangEntry) {
v1.Set(menuLangEntry, v)
}
}
}
}
}
// Add menu definitions from theme not found in project
if v2.IsSet("menu") {
v2menus := v2.GetStringMap(menuKey)
for k, v := range v2menus {
menuEntry := menuKey + "." + k
if !v1.IsSet(menuEntry) {
v1.SetDefault(menuEntry, v)
}
}
}
return nil
}
func mergeStringMapKeepLeft(rootKey, key string, v1, v2 config.Provider) {
if !v2.IsSet(key) {
return
}
if !v1.IsSet(key) && !(rootKey != "" && rootKey != key && v1.IsSet(rootKey)) {
v1.Set(key, v2.Get(key))
return
}
m1 := v1.GetStringMap(key)
m2 := v2.GetStringMap(key)
for k, v := range m2 {
if _, found := m1[k]; !found {
if rootKey != "" && v1.IsSet(rootKey+"."+k) {
continue
}
m1[k] = v
}
}
}
func loadDefaultSettingsFor(v *viper.Viper) error {
c, err := helpers.NewContentSpec(v)
if err != nil {
return err
}
v.RegisterAlias("indexes", "taxonomies")
v.SetDefault("cleanDestinationDir", false)
v.SetDefault("watch", false)
v.SetDefault("metaDataFormat", "toml")
v.SetDefault("contentDir", "content")
v.SetDefault("layoutDir", "layouts")
v.SetDefault("staticDir", "static")
v.SetDefault("resourceDir", "resources")
v.SetDefault("archetypeDir", "archetypes")
v.SetDefault("publishDir", "public")
v.SetDefault("dataDir", "data")
v.SetDefault("i18nDir", "i18n")
v.SetDefault("themesDir", "themes")
v.SetDefault("buildDrafts", false)
v.SetDefault("buildFuture", false)
v.SetDefault("buildExpired", false)
v.SetDefault("uglyURLs", false)
v.SetDefault("verbose", false)
v.SetDefault("ignoreCache", false)
v.SetDefault("canonifyURLs", false)
v.SetDefault("relativeURLs", false)
v.SetDefault("removePathAccents", false)
v.SetDefault("titleCaseStyle", "AP")
v.SetDefault("taxonomies", map[string]string{"tag": "tags", "category": "categories"})
v.SetDefault("permalinks", make(PermalinkOverrides, 0))
v.SetDefault("sitemap", Sitemap{Priority: -1, Filename: "sitemap.xml"})
v.SetDefault("pygmentsStyle", "monokai")
v.SetDefault("pygmentsUseClasses", false)
v.SetDefault("pygmentsCodeFences", false)
v.SetDefault("pygmentsUseClassic", false)
v.SetDefault("pygmentsOptions", "")
v.SetDefault("disableLiveReload", false)
v.SetDefault("pluralizeListTitles", true)
v.SetDefault("preserveTaxonomyNames", false)
v.SetDefault("forceSyncStatic", false)
v.SetDefault("footnoteAnchorPrefix", "")
v.SetDefault("footnoteReturnLinkContents", "")
v.SetDefault("newContentEditor", "")
v.SetDefault("paginate", 10)
v.SetDefault("paginatePath", "page")
v.SetDefault("summaryLength", 70)
v.SetDefault("blackfriday", c.BlackFriday)
v.SetDefault("rSSUri", "index.xml")
v.SetDefault("rssLimit", -1)
v.SetDefault("sectionPagesMenu", "")
v.SetDefault("disablePathToLower", false)
v.SetDefault("hasCJKLanguage", false)
v.SetDefault("enableEmoji", false)
v.SetDefault("pygmentsCodeFencesGuessSyntax", false)
v.SetDefault("useModTimeAsFallback", false)
v.SetDefault("defaultContentLanguage", "en")
v.SetDefault("defaultContentLanguageInSubdir", false)
v.SetDefault("enableMissingTranslationPlaceholders", false)
v.SetDefault("enableGitInfo", false)
v.SetDefault("ignoreFiles", make([]string, 0))
v.SetDefault("disableAliases", false)
v.SetDefault("debug", false)
v.SetDefault("disableFastRender", false)
v.SetDefault("timeout", 10000) // 10 seconds
// Remove in Hugo 0.39
if v.GetBool("useModTimeAsFallback") {
helpers.Deprecated("Site config", "useModTimeAsFallback", `Replace with this in your config.toml:
[frontmatter]
date = [ "date",":fileModTime", ":default"]
lastmod = ["lastmod" ,":fileModTime", ":default"]
`, false)
}
return nil
}