1 files changed, 168 insertions, 0 deletions
diff --git a/cache/filecache/filecache_config.go b/cache/filecache/filecache_config.go
new file mode 100644
index 000000000..f83e19e0e
--- /dev/null
+++ b/cache/filecache/filecache_config.go
@@ -0,0 +1,168 @@
+// Copyright 2018 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 filecache
+
+import (
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/gohugoio/hugo/helpers"
+	"github.com/gohugoio/hugo/hugolib/paths"
+
+	"github.com/bep/mapstructure"
+	"github.com/pkg/errors"
+	"github.com/spf13/afero"
+)
+
+const (
+	cachesConfigKey = "caches"
+
+	resourcesGenDir = ":resourceDir/_gen"
+)
+
+var defaultCacheConfig = cacheConfig{
+	MaxAge: -1, // Never expire
+	Dir:    ":cacheDir",
+}
+
+const (
+	cacheKeyGetJSON = "getjson"
+	cacheKeyGetCSV  = "getcsv"
+	cacheKeyImages  = "images"
+	cacheKeyAssets  = "assets"
+)
+
+var defaultCacheConfigs = map[string]cacheConfig{
+	cacheKeyGetJSON: defaultCacheConfig,
+	cacheKeyGetCSV:  defaultCacheConfig,
+	cacheKeyImages: cacheConfig{
+		MaxAge: -1,
+		Dir:    resourcesGenDir,
+	},
+	cacheKeyAssets: cacheConfig{
+		MaxAge: -1,
+		Dir:    resourcesGenDir,
+	},
+}
+
+type cachesConfig map[string]cacheConfig
+
+type cacheConfig struct {
+	// Max age of cache entries in this cache. Any items older than this will
+	// be removed and not returned from the cache.
+	// -1 means forever, 0 means cache is disabled.
+	MaxAge int
+
+	// The directory where files are stored.
+	Dir string
+}
+
+// GetJSONCache gets the file cache for getJSON.
+func (f Caches) GetJSONCache() *Cache {
+	return f[cacheKeyGetJSON]
+}
+
+// GetCSVCache gets the file cache for getCSV.
+func (f Caches) GetCSVCache() *Cache {
+	return f[cacheKeyGetCSV]
+}
+
+// ImageCache gets the file cache for processed images.
+func (f Caches) ImageCache() *Cache {
+	return f[cacheKeyImages]
+}
+
+// AssetsCache gets the file cache for assets (processed resources, SCSS etc.).
+func (f Caches) AssetsCache() *Cache {
+	return f[cacheKeyAssets]
+}
+
+func decodeConfig(p *paths.Paths) (cachesConfig, error) {
+	c := make(cachesConfig)
+	valid := make(map[string]bool)
+	// Add defaults
+	for k, v := range defaultCacheConfigs {
+		c[k] = v
+		valid[k] = true
+	}
+
+	cfg := p.Cfg
+
+	m := cfg.GetStringMap(cachesConfigKey)
+
+	_, isOsFs := p.Fs.Source.(*afero.OsFs)
+
+	for k, v := range m {
+		cc := defaultCacheConfig
+
+		if err := mapstructure.WeakDecode(v, &cc); err != nil {
+			return nil, err
+		}
+
+		if cc.Dir == "" {
+			return c, errors.New("must provide cache Dir")
+		}
+
+		name := strings.ToLower(k)
+		if !valid[name] {
+			return nil, errors.Errorf("%q is not a valid cache name", name)
+		}
+
+		c[name] = cc
+	}
+
+	// This is a very old flag in Hugo, but we need to respect it.
+	disabled := cfg.GetBool("ignoreCache")
+
+	for k, v := range c {
+		v.Dir = filepath.Clean(v.Dir)
+		dir := filepath.ToSlash(v.Dir)
+		parts := strings.Split(dir, "/")
+		first := parts[0]
+
+		if strings.HasPrefix(first, ":") {
+			resolved, err := resolveDirPlaceholder(p, first)
+			if err != nil {
+				return c, err
+			}
+			resolved = filepath.ToSlash(resolved)
+
+			v.Dir = filepath.FromSlash(path.Join((append([]string{resolved}, parts[1:]...))...))
+
+		} else if isOsFs && !path.IsAbs(dir) {
+			return c, errors.Errorf("%q must either start with a placeholder (e.g. :cacheDir, :resourceDir) or be absolute", v.Dir)
+		}
+
+		if disabled {
+			v.MaxAge = 0
+		}
+
+		c[k] = v
+	}
+
+	return c, nil
+}
+
+// Resolves :resourceDir => /myproject/resources etc., :cacheDir => ...
+func resolveDirPlaceholder(p *paths.Paths, placeholder string) (string, error) {
+	switch strings.ToLower(placeholder) {
+	case ":resourcedir":
+		return p.AbsResourcesDir, nil
+	case ":cachedir":
+		return helpers.GetCacheDir(p.Fs.Source, p.Cfg)
+	}
+
+	return "", errors.Errorf("%q is not a valid placeholder (valid values are :cacheDir or :resourceDir)", placeholder)
+}