1 files changed, 285 insertions, 0 deletions
diff --git a/deps/deps.go b/deps/deps.go
new file mode 100644
index 000000000..2b66a153f
--- /dev/null
+++ b/deps/deps.go
@@ -0,0 +1,285 @@
+package deps
+
+import (
+	"sync"
+	"time"
+
+	"github.com/gohugoio/hugo/common/loggers"
+
+	"github.com/gohugoio/hugo/config"
+	"github.com/gohugoio/hugo/helpers"
+	"github.com/gohugoio/hugo/hugofs"
+	"github.com/gohugoio/hugo/langs"
+	"github.com/gohugoio/hugo/media"
+	"github.com/gohugoio/hugo/metrics"
+	"github.com/gohugoio/hugo/output"
+	"github.com/gohugoio/hugo/resource"
+	"github.com/gohugoio/hugo/source"
+	"github.com/gohugoio/hugo/tpl"
+	jww "github.com/spf13/jwalterweatherman"
+)
+
+// Deps holds dependencies used by many.
+// There will be normally only one instance of deps in play
+// at a given time, i.e. one per Site built.
+type Deps struct {
+
+	// The logger to use.
+	Log *jww.Notepad `json:"-"`
+
+	// Used to log errors that may repeat itself many times.
+	DistinctErrorLog *helpers.DistinctLogger
+
+	// The templates to use. This will usually implement the full tpl.TemplateHandler.
+	Tmpl tpl.TemplateFinder `json:"-"`
+
+	// We use this to parse and execute ad-hoc text templates.
+	TextTmpl tpl.TemplateParseFinder `json:"-"`
+
+	// The file systems to use.
+	Fs *hugofs.Fs `json:"-"`
+
+	// The PathSpec to use
+	*helpers.PathSpec `json:"-"`
+
+	// The ContentSpec to use
+	*helpers.ContentSpec `json:"-"`
+
+	// The SourceSpec to use
+	SourceSpec *source.SourceSpec `json:"-"`
+
+	// The Resource Spec to use
+	ResourceSpec *resource.Spec
+
+	// The configuration to use
+	Cfg config.Provider `json:"-"`
+
+	// The translation func to use
+	Translate func(translationID string, args ...interface{}) string `json:"-"`
+
+	Language *langs.Language
+
+	// All the output formats available for the current site.
+	OutputFormatsConfig output.Formats
+
+	templateProvider ResourceProvider
+	WithTemplate     func(templ tpl.TemplateHandler) error `json:"-"`
+
+	translationProvider ResourceProvider
+
+	Metrics metrics.Provider
+
+	// Timeout is configurable in site config.
+	Timeout time.Duration
+
+	// BuildStartListeners will be notified before a build starts.
+	BuildStartListeners *Listeners
+}
+
+// Listeners represents an event listener.
+type Listeners struct {
+	sync.Mutex
+
+	// A list of funcs to be notified about an event.
+	listeners []func()
+}
+
+// Add adds a function to a Listeners instance.
+func (b *Listeners) Add(f func()) {
+	b.Lock()
+	defer b.Unlock()
+	b.listeners = append(b.listeners, f)
+}
+
+// Notify executes all listener functions.
+func (b *Listeners) Notify() {
+	b.Lock()
+	defer b.Unlock()
+	for _, notify := range b.listeners {
+		notify()
+	}
+}
+
+// ResourceProvider is used to create and refresh, and clone resources needed.
+type ResourceProvider interface {
+	Update(deps *Deps) error
+	Clone(deps *Deps) error
+}
+
+// TemplateHandler returns the used tpl.TemplateFinder as tpl.TemplateHandler.
+func (d *Deps) TemplateHandler() tpl.TemplateHandler {
+	return d.Tmpl.(tpl.TemplateHandler)
+}
+
+// LoadResources loads translations and templates.
+func (d *Deps) LoadResources() error {
+	// Note that the translations need to be loaded before the templates.
+	if err := d.translationProvider.Update(d); err != nil {
+		return err
+	}
+
+	if err := d.templateProvider.Update(d); err != nil {
+		return err
+	}
+
+	if th, ok := d.Tmpl.(tpl.TemplateHandler); ok {
+		th.PrintErrors()
+	}
+
+	return nil
+}
+
+// New initializes a Dep struct.
+// Defaults are set for nil values,
+// but TemplateProvider, TranslationProvider and Language are always required.
+func New(cfg DepsCfg) (*Deps, error) {
+	var (
+		logger = cfg.Logger
+		fs     = cfg.Fs
+	)
+
+	if cfg.TemplateProvider == nil {
+		panic("Must have a TemplateProvider")
+	}
+
+	if cfg.TranslationProvider == nil {
+		panic("Must have a TranslationProvider")
+	}
+
+	if cfg.Language == nil {
+		panic("Must have a Language")
+	}
+
+	if logger == nil {
+		logger = loggers.NewErrorLogger()
+	}
+
+	if fs == nil {
+		// Default to the production file system.
+		fs = hugofs.NewDefault(cfg.Language)
+	}
+
+	ps, err := helpers.NewPathSpec(fs, cfg.Language)
+
+	if err != nil {
+		return nil, err
+	}
+
+	resourceSpec, err := resource.NewSpec(ps, logger, cfg.OutputFormats, cfg.MediaTypes)
+	if err != nil {
+		return nil, err
+	}
+
+	contentSpec, err := helpers.NewContentSpec(cfg.Language)
+	if err != nil {
+		return nil, err
+	}
+
+	sp := source.NewSourceSpec(ps, fs.Source)
+
+	timeoutms := cfg.Language.GetInt("timeout")
+	if timeoutms <= 0 {
+		timeoutms = 3000
+	}
+
+	distinctErrorLogger := helpers.NewDistinctLogger(logger.ERROR)
+
+	d := &Deps{
+		Fs:                  fs,
+		Log:                 logger,
+		DistinctErrorLog:    distinctErrorLogger,
+		templateProvider:    cfg.TemplateProvider,
+		translationProvider: cfg.TranslationProvider,
+		WithTemplate:        cfg.WithTemplate,
+		PathSpec:            ps,
+		ContentSpec:         contentSpec,
+		SourceSpec:          sp,
+		ResourceSpec:        resourceSpec,
+		Cfg:                 cfg.Language,
+		Language:            cfg.Language,
+		BuildStartListeners: &Listeners{},
+		Timeout:             time.Duration(timeoutms) * time.Millisecond,
+	}
+
+	if cfg.Cfg.GetBool("templateMetrics") {
+		d.Metrics = metrics.NewProvider(cfg.Cfg.GetBool("templateMetricsHints"))
+	}
+
+	return d, nil
+}
+
+// ForLanguage creates a copy of the Deps with the language dependent
+// parts switched out.
+func (d Deps) ForLanguage(cfg DepsCfg) (*Deps, error) {
+	l := cfg.Language
+	var err error
+
+	d.PathSpec, err = helpers.NewPathSpecWithBaseBaseFsProvided(d.Fs, l, d.BaseFs)
+	if err != nil {
+		return nil, err
+	}
+
+	d.ContentSpec, err = helpers.NewContentSpec(l)
+	if err != nil {
+		return nil, err
+	}
+
+	// The resource cache is global so reuse.
+	// TODO(bep) clean up these inits.
+	resourceCache := d.ResourceSpec.ResourceCache
+	d.ResourceSpec, err = resource.NewSpec(d.PathSpec, d.Log, cfg.OutputFormats, cfg.MediaTypes)
+	if err != nil {
+		return nil, err
+	}
+	d.ResourceSpec.ResourceCache = resourceCache
+
+	d.Cfg = l
+	d.Language = l
+
+	if err := d.translationProvider.Clone(&d); err != nil {
+		return nil, err
+	}
+
+	if err := d.templateProvider.Clone(&d); err != nil {
+		return nil, err
+	}
+
+	d.BuildStartListeners = &Listeners{}
+
+	return &d, nil
+
+}
+
+// DepsCfg contains configuration options that can be used to configure Hugo
+// on a global level, i.e. logging etc.
+// Nil values will be given default values.
+type DepsCfg struct {
+
+	// The Logger to use.
+	Logger *jww.Notepad
+
+	// The file systems to use
+	Fs *hugofs.Fs
+
+	// The language to use.
+	Language *langs.Language
+
+	// The configuration to use.
+	Cfg config.Provider
+
+	// The media types configured.
+	MediaTypes media.Types
+
+	// The output formats configured.
+	OutputFormats output.Formats
+
+	// Template handling.
+	TemplateProvider ResourceProvider
+	WithTemplate     func(templ tpl.TemplateHandler) error
+
+	// i18n handling.
+	TranslationProvider ResourceProvider
+
+	// Whether we are in running (server) mode
+	Running bool
+}