gojekyll/collections/collection.go

package collections

import (
	"path/filepath"

	"github.com/osteele/gojekyll/config"
	"github.com/osteele/gojekyll/constants"
	"github.com/osteele/gojekyll/pages"
	"github.com/osteele/gojekyll/templates"
	"github.com/osteele/liquid/generics"
)

// Collection is a Jekyll collection https://jekyllrb.com/docs/collections/.
type Collection struct {
	Name      string
	Metadata  map[string]interface{}
	container pages.Container
	pages     []pages.Document
}

// NewCollection creates a new Collection
func NewCollection(name string, metadata map[string]interface{}, c pages.Container) *Collection {
	return &Collection{
		Name:      name,
		Metadata:  metadata,
		container: c,
	}
}

// Config is in the page.Container interface.
func (c *Collection) Config() config.Config {
	return c.container.Config()
}

// OutputExt is in the page.Container interface.
func (c *Collection) OutputExt(pathname string) string {
	return c.container.OutputExt(pathname)
}

// PathPrefix is in the page.Container interface.
// PathPrefix returns the collection's directory prefix, e.g. "_posts/"
func (c *Collection) PathPrefix() string { return filepath.FromSlash("_" + c.Name + "/") }

// IsPostsCollection returns true if the collection is the special "posts" collection.
func (c *Collection) IsPostsCollection() bool { return c.Name == "posts" }

// Output returns a bool indicating whether files in this collection should be written.
func (c *Collection) Output() bool { return templates.VariableMap(c.Metadata).Bool("output", false) }

// Pages is a list of pages.
func (c *Collection) Pages() []pages.Document {
	return c.pages
}

// TemplateVariable returns an array of page objects, for use as the template variable
// value of the collection.
func (c *Collection) TemplateVariable(ctx pages.RenderingContext, includeContent bool) ([]interface{}, error) {
	d := []interface{}{}
	for _, p := range c.Pages() {
		v := p.PageVariables()
		dp, ok := p.(*pages.Page)
		if includeContent && ok {
			c, err := dp.Content(ctx)
			if err != nil {
				return nil, err
			}
			v = templates.MergeVariableMaps(v, map[string]interface{}{
				"content": string(c),
			})
		}
		d = append(d, v)
	}
	if c.IsPostsCollection() {
		generics.SortByProperty(d, "date", true)
	}
	out := make([]interface{}, len(d))
	for i, v := range d {
		out[len(d)-1-i] = v
	}
	return out, nil
}

// PermalinkPattern returns the permalink pattern for this collection.
func (c *Collection) PermalinkPattern() string {
	defaultPattern := constants.DefaultCollectionPermalinkPattern
	if c.IsPostsCollection() {
		defaultPattern = constants.DefaultPostsCollectionPermalinkPattern
	}
	return templates.VariableMap(c.Metadata).String("permalink", defaultPattern)
}