Add readFile template func

This also includes a refactor of the hugofs package and its usage.

The motivation for that is:

The Afero filesystems are brilliant. Hugo's way of adding a dozen of global variables for the different filesystems was a mistake. In readFile (and also in some other places in Hugo today) we need a way to restrict the access inside the working dir. We could use ioutil.ReadFile and implement the path checking, checking the base path and the dots ("..") etc. But it is obviously better to use an Afero BasePathFs combined witha ReadOnlyFs. We could create a use-once-filesystem and handle the initialization ourselves, but since this is also useful to others and the initialization depends on some other global state (which would mean to create a new file system on every invocation), we might as well do it properly and encapsulate the predefined set of filesystems. This change also leads the way, if needed, to encapsulate the file systems in a struct, making it possible to have several file system sets in action at once (parallel multilanguage site building? With Moore's law and all...)

Fixes #1551

32 files changed, 400 insertions, 152 deletions

diff --git a/commands/gendoc.go b/commands/gendoc.go
index 0f65e7dc9..046d3839c 100644
--- a/commands/gendoc.go
+++ b/commands/gendoc.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -51,9 +51,9 @@ for rendering in Hugo.`,
 		if !strings.HasSuffix(gendocdir, helpers.FilePathSeparator) {
 			gendocdir += helpers.FilePathSeparator
 		}
-		if found, _ := helpers.Exists(gendocdir, hugofs.OsFs); !found {
+		if found, _ := helpers.Exists(gendocdir, hugofs.Os()); !found {
 			jww.FEEDBACK.Println("Directory", gendocdir, "does not exist, creating...")
-			hugofs.OsFs.MkdirAll(gendocdir, 0777)
+			hugofs.Os().MkdirAll(gendocdir, 0777)
 		}
 		now := time.Now().Format(time.RFC3339)
 		prepender := func(filename string) string {
diff --git a/commands/genman.go b/commands/genman.go
index e12d02773..d1f54ae31 100644
--- a/commands/genman.go
+++ b/commands/genman.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -41,9 +41,9 @@ in the "man" directory under the current directory.`,
 		if !strings.HasSuffix(genmandir, helpers.FilePathSeparator) {
 			genmandir += helpers.FilePathSeparator
 		}
-		if found, _ := helpers.Exists(genmandir, hugofs.OsFs); !found {
+		if found, _ := helpers.Exists(genmandir, hugofs.Os()); !found {
 			jww.FEEDBACK.Println("Directory", genmandir, "does not exist, creating...")
-			hugofs.OsFs.MkdirAll(genmandir, 0777)
+			hugofs.Os().MkdirAll(genmandir, 0777)
 		}
 		cmd.Root().DisableAutoGenTag = true
 
diff --git a/commands/hugo.go b/commands/hugo.go
index 19fcb57f7..131879ce9 100644
--- a/commands/hugo.go
+++ b/commands/hugo.go
@@ -423,14 +423,14 @@ func InitializeConfig(subCmdVs ...*cobra.Command) error {
 		if helpers.FilePathSeparator != cacheDir[len(cacheDir)-1:] {
 			cacheDir = cacheDir + helpers.FilePathSeparator
 		}
-		isDir, err := helpers.DirExists(cacheDir, hugofs.SourceFs)
+		isDir, err := helpers.DirExists(cacheDir, hugofs.Source())
 		utils.CheckErr(err)
 		if isDir == false {
 			mkdir(cacheDir)
 		}
 		viper.Set("CacheDir", cacheDir)
 	} else {
-		viper.Set("CacheDir", helpers.GetTempDir("hugo_cache", hugofs.SourceFs))
+		viper.Set("CacheDir", helpers.GetTempDir("hugo_cache", hugofs.Source()))
 	}
 
 	if verboseLog || logging || (viper.IsSet("LogFile") && viper.GetString("LogFile") != "") {
@@ -453,6 +453,9 @@ func InitializeConfig(subCmdVs ...*cobra.Command) error {
 
 	jww.INFO.Println("Using config file:", viper.ConfigFileUsed())
 
+	// Init file systems. This may be changed at a later point.
+	hugofs.InitDefaultFs()
+
 	themeDir := helpers.GetThemeDir()
 	if themeDir != "" {
 		if _, err := os.Stat(themeDir); os.IsNotExist(err) {
@@ -498,7 +501,7 @@ func build(watches ...bool) error {
 	// This is only used for benchmark testing. Cause the content is only visible
 	// in memory
 	if renderToMemory {
-		hugofs.DestinationFS = new(afero.MemMapFs)
+		hugofs.SetDestination(new(afero.MemMapFs))
 		// Rendering to memoryFS, publish to Root regardless of publishDir.
 		viper.Set("PublishDir", "/")
 	}
@@ -524,7 +527,7 @@ func build(watches ...bool) error {
 }
 
 func getStaticSourceFs() afero.Fs {
-	source := hugofs.SourceFs
+	source := hugofs.Source()
 	themeDir, err := helpers.GetThemeStaticDirPath()
 	staticDir := helpers.GetStaticDirPath() + helpers.FilePathSeparator
 
@@ -563,8 +566,8 @@ func getStaticSourceFs() afero.Fs {
 	jww.INFO.Println("using a UnionFS for static directory comprised of:")
 	jww.INFO.Println("Base:", themeDir)
 	jww.INFO.Println("Overlay:", staticDir)
-	base := afero.NewReadOnlyFs(afero.NewBasePathFs(hugofs.SourceFs, themeDir))
-	overlay := afero.NewReadOnlyFs(afero.NewBasePathFs(hugofs.SourceFs, staticDir))
+	base := afero.NewReadOnlyFs(afero.NewBasePathFs(hugofs.Source(), themeDir))
+	overlay := afero.NewReadOnlyFs(afero.NewBasePathFs(hugofs.Source(), staticDir))
 	return afero.NewCopyOnWriteFs(base, overlay)
 }
 
@@ -587,7 +590,7 @@ func copyStatic() error {
 	syncer := fsync.NewSyncer()
 	syncer.NoTimes = viper.GetBool("notimes")
 	syncer.SrcFs = staticSourceFs
-	syncer.DestFs = hugofs.DestinationFS
+	syncer.DestFs = hugofs.Destination()
 	// Now that we are using a unionFs for the static directories
 	// We can effectively clean the publishDir on initial sync
 	syncer.Delete = viper.GetBool("cleanDestinationDir")
@@ -653,12 +656,12 @@ func getDirList() []string {
 		return nil
 	}
 
-	helpers.SymbolicWalk(hugofs.SourceFs, dataDir, walker)
-	helpers.SymbolicWalk(hugofs.SourceFs, helpers.AbsPathify(viper.GetString("ContentDir")), walker)
-	helpers.SymbolicWalk(hugofs.SourceFs, helpers.AbsPathify(viper.GetString("LayoutDir")), walker)
-	helpers.SymbolicWalk(hugofs.SourceFs, helpers.AbsPathify(viper.GetString("StaticDir")), walker)
+	helpers.SymbolicWalk(hugofs.Source(), dataDir, walker)
+	helpers.SymbolicWalk(hugofs.Source(), helpers.AbsPathify(viper.GetString("ContentDir")), walker)
+	helpers.SymbolicWalk(hugofs.Source(), helpers.AbsPathify(viper.GetString("LayoutDir")), walker)
+	helpers.SymbolicWalk(hugofs.Source(), helpers.AbsPathify(viper.GetString("StaticDir")), walker)
 	if helpers.ThemeSet() {
-		helpers.SymbolicWalk(hugofs.SourceFs, helpers.AbsPathify(viper.GetString("themesDir")+"/"+viper.GetString("theme")), walker)
+		helpers.SymbolicWalk(hugofs.Source(), helpers.AbsPathify(viper.GetString("themesDir")+"/"+viper.GetString("theme")), walker)
 	}
 
 	return a
@@ -770,8 +773,8 @@ func NewWatcher(port int) error {
 					// recursively add new directories to watch list
 					// When mkdir -p is used, only the top directory triggers an event (at least on OSX)
 					if ev.Op&fsnotify.Create == fsnotify.Create {
-						if s, err := hugofs.SourceFs.Stat(ev.Name); err == nil && s.Mode().IsDir() {
-							helpers.SymbolicWalk(hugofs.SourceFs, ev.Name, walkAdder)
+						if s, err := hugofs.Source().Stat(ev.Name); err == nil && s.Mode().IsDir() {
+							helpers.SymbolicWalk(hugofs.Source(), ev.Name, walkAdder)
 						}
 					}
 
@@ -813,7 +816,7 @@ func NewWatcher(port int) error {
 						syncer := fsync.NewSyncer()
 						syncer.NoTimes = viper.GetBool("notimes")
 						syncer.SrcFs = staticSourceFs
-						syncer.DestFs = hugofs.DestinationFS
+						syncer.DestFs = hugofs.Destination()
 
 						// prevent spamming the log on changes
 						logger := helpers.NewDistinctFeedbackLogger()
@@ -858,7 +861,7 @@ func NewWatcher(port int) error {
 									// If file doesn't exist in any static dir, remove it
 									toRemove := filepath.Join(publishDir, relPath)
 									logger.Println("File no longer exists in static dir, removing", toRemove)
-									hugofs.DestinationFS.RemoveAll(toRemove)
+									hugofs.Destination().RemoveAll(toRemove)
 								} else if err == nil {
 									// If file still exists, sync it
 									logger.Println("Syncing", relPath, "to", publishDir)
@@ -939,7 +942,7 @@ func isThemeVsHugoVersionMismatch() (mismatch bool, requiredMinVersion string) {
 
 	themeDir := helpers.GetThemeDir()
 
-	fs := hugofs.SourceFs
+	fs := hugofs.Source()
 	path := filepath.Join(themeDir, "theme.toml")
 
 	exists, err := helpers.Exists(path, fs)
diff --git a/commands/import_jekyll.go b/commands/import_jekyll.go
index 26020b0f9..20356f1e1 100644
--- a/commands/import_jekyll.go
+++ b/commands/import_jekyll.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -124,7 +124,7 @@ func importFromJekyll(cmd *cobra.Command, args []string) error {
 		return convertJekyllPost(path, relPath, targetDir, draft)
 	}
 
-	err = helpers.SymbolicWalk(hugofs.OsFs, jekyllRoot, callback)
+	err = helpers.SymbolicWalk(hugofs.Os(), jekyllRoot, callback)
 
 	if err != nil {
 		return err
@@ -139,7 +139,7 @@ func importFromJekyll(cmd *cobra.Command, args []string) error {
 
 // TODO: Consider calling doNewSite() instead?
 func createSiteFromJekyll(jekyllRoot, targetDir string, force bool) error {
-	fs := hugofs.SourceFs
+	fs := hugofs.Source()
 	if exists, _ := helpers.Exists(targetDir, fs); exists {
 		if isDir, _ := helpers.IsDir(targetDir, fs); !isDir {
 			return errors.New("Target path \"" + targetDir + "\" already exists but not a directory")
@@ -187,7 +187,7 @@ func createSiteFromJekyll(jekyllRoot, targetDir string, force bool) error {
 }
 
 func loadJekyllConfig(jekyllRoot string) map[string]interface{} {
-	fs := hugofs.SourceFs
+	fs := hugofs.Source()
 	path := filepath.Join(jekyllRoot, "_config.yml")
 
 	exists, err := helpers.Exists(path, fs)
@@ -252,7 +252,7 @@ func createConfigFromJekyll(inpath string, kind string, jekyllConfig map[string]
 		return err
 	}
 
-	err = helpers.WriteToDisk(filepath.Join(inpath, "config."+kind), bytes.NewReader(by), hugofs.SourceFs)
+	err = helpers.WriteToDisk(filepath.Join(inpath, "config."+kind), bytes.NewReader(by), hugofs.Source())
 	if err != nil {
 		return
 	}
diff --git a/commands/new.go b/commands/new.go
index 4fc000319..c3f04f471 100644
--- a/commands/new.go
+++ b/commands/new.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -110,7 +110,7 @@ func NewContent(cmd *cobra.Command, args []string) error {
 		kind = contentType
 	}
 
-	return create.NewContent(hugofs.SourceFs, kind, createpath)
+	return create.NewContent(hugofs.Source(), kind, createpath)
 }
 
 func doNewSite(basepath string, force bool) error {
@@ -123,12 +123,12 @@ func doNewSite(basepath string, force bool) error {
 		filepath.Join(basepath, "themes"),
 	}
 
-	if exists, _ := helpers.Exists(basepath, hugofs.SourceFs); exists {
-		if isDir, _ := helpers.IsDir(basepath, hugofs.SourceFs); !isDir {
+	if exists, _ := helpers.Exists(basepath, hugofs.Source()); exists {
+		if isDir, _ := helpers.IsDir(basepath, hugofs.Source()); !isDir {
 			return errors.New(basepath + " already exists but not a directory")
 		}
 
-		isEmpty, _ := helpers.IsEmpty(basepath, hugofs.SourceFs)
+		isEmpty, _ := helpers.IsEmpty(basepath, hugofs.Source())
 
 		switch {
 		case !isEmpty && !force:
@@ -137,7 +137,7 @@ func doNewSite(basepath string, force bool) error {
 		case !isEmpty && force:
 			all := append(dirs, filepath.Join(basepath, "config."+configFormat))
 			for _, path := range all {
-				if exists, _ := helpers.Exists(path, hugofs.SourceFs); exists {
+				if exists, _ := helpers.Exists(path, hugofs.Source()); exists {
 					return errors.New(path + " already exists")
 				}
 			}
@@ -145,7 +145,7 @@ func doNewSite(basepath string, force bool) error {
 	}
 
 	for _, dir := range dirs {
-		hugofs.SourceFs.MkdirAll(dir, 0777)
+		hugofs.Source().MkdirAll(dir, 0777)
 	}
 
 	createConfig(basepath, configFormat)
@@ -185,7 +185,7 @@ func NewTheme(cmd *cobra.Command, args []string) error {
 	createpath := helpers.AbsPathify(filepath.Join(viper.GetString("themesDir"), args[0]))
 	jww.INFO.Println("creating theme at", createpath)
 
-	if x, _ := helpers.Exists(createpath, hugofs.SourceFs); x {
+	if x, _ := helpers.Exists(createpath, hugofs.Source()); x {
 		return newUserError(createpath, "already exists")
 	}
 
@@ -204,7 +204,7 @@ func NewTheme(cmd *cobra.Command, args []string) error {
 
 	archDefault := []byte("+++\n+++\n")
 
-	err := helpers.WriteToDisk(filepath.Join(createpath, "archetypes", "default.md"), bytes.NewReader(archDefault), hugofs.SourceFs)
+	err := helpers.WriteToDisk(filepath.Join(createpath, "archetypes", "default.md"), bytes.NewReader(archDefault), hugofs.Source())
 	if err != nil {
 		return err
 	}
@@ -234,7 +234,7 @@ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 `)
 
-	err = helpers.WriteToDisk(filepath.Join(createpath, "LICENSE.md"), bytes.NewReader(by), hugofs.SourceFs)
+	err = helpers.WriteToDisk(filepath.Join(createpath, "LICENSE.md"), bytes.NewReader(by), hugofs.Source())
 	if err != nil {
 		return err
 	}
@@ -256,7 +256,7 @@ func mkdir(x ...string) {
 func touchFile(x ...string) {
 	inpath := filepath.Join(x...)
 	mkdir(filepath.Dir(inpath))
-	err := helpers.WriteToDisk(inpath, bytes.NewReader([]byte{}), hugofs.SourceFs)
+	err := helpers.WriteToDisk(inpath, bytes.NewReader([]byte{}), hugofs.Source())
 	if err != nil {
 		jww.FATAL.Fatalln(err)
 	}
@@ -287,7 +287,7 @@ min_version = 0.15
   repo = ""
 `)
 
-	err = helpers.WriteToDisk(filepath.Join(inpath, "theme.toml"), bytes.NewReader(by), hugofs.SourceFs)
+	err = helpers.WriteToDisk(filepath.Join(inpath, "theme.toml"), bytes.NewReader(by), hugofs.Source())
 	if err != nil {
 		return
 	}
@@ -321,7 +321,7 @@ func createConfig(inpath string, kind string) (err error) {
 		return err
 	}
 
-	err = helpers.WriteToDisk(filepath.Join(inpath, "config."+kind), bytes.NewReader(by), hugofs.SourceFs)
+	err = helpers.WriteToDisk(filepath.Join(inpath, "config."+kind), bytes.NewReader(by), hugofs.Source())
 	if err != nil {
 		return
 	}
diff --git a/commands/new_test.go b/commands/new_test.go
index e74e9cfcc..5991e1813 100644
--- a/commands/new_test.go
+++ b/commands/new_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -18,7 +18,6 @@ import (
 	"path/filepath"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/stretchr/testify/assert"
 )
@@ -41,14 +40,14 @@ func checkNewSiteInited(basepath string, t *testing.T) {
 	}
 
 	for _, path := range paths {
-		_, err := hugofs.SourceFs.Stat(path)
+		_, err := hugofs.Source().Stat(path)
 		assert.Nil(t, err)
 	}
 }
 
 func TestDoNewSite(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
-	hugofs.SourceFs = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	err := doNewSite(basepath, false)
 	assert.Nil(t, err)
 
@@ -57,17 +56,17 @@ func TestDoNewSite(t *testing.T) {
 
 func TestDoNewSite_noerror_base_exists_but_empty(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
-	hugofs.SourceFs = new(afero.MemMapFs)
-	hugofs.SourceFs.MkdirAll(basepath, 777)
+	hugofs.InitMemFs()
+	hugofs.Source().MkdirAll(basepath, 777)
 	err := doNewSite(basepath, false)
 	assert.Nil(t, err)
 }
 
 func TestDoNewSite_error_base_exists(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
-	hugofs.SourceFs = new(afero.MemMapFs)
-	hugofs.SourceFs.MkdirAll(basepath, 777)
-	hugofs.SourceFs.Create(filepath.Join(basepath, "foo"))
+	hugofs.InitMemFs()
+	hugofs.Source().MkdirAll(basepath, 777)
+	hugofs.Source().Create(filepath.Join(basepath, "foo"))
 	// Since the directory already exists and isn't empty, expect an error
 	err := doNewSite(basepath, false)
 	assert.NotNil(t, err)
@@ -75,8 +74,8 @@ func TestDoNewSite_error_base_exists(t *testing.T) {
 
 func TestDoNewSite_force_empty_dir(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
-	hugofs.SourceFs = new(afero.MemMapFs)
-	hugofs.SourceFs.MkdirAll(basepath, 777)
+	hugofs.InitMemFs()
+	hugofs.Source().MkdirAll(basepath, 777)
 	err := doNewSite(basepath, true)
 	assert.Nil(t, err)
 
@@ -86,8 +85,8 @@ func TestDoNewSite_force_empty_dir(t *testing.T) {
 func TestDoNewSite_error_force_dir_inside_exists(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
 	contentPath := filepath.Join(basepath, "content")
-	hugofs.SourceFs = new(afero.MemMapFs)
-	hugofs.SourceFs.MkdirAll(contentPath, 777)
+	hugofs.InitMemFs()
+	hugofs.Source().MkdirAll(contentPath, 777)
 	err := doNewSite(basepath, true)
 	assert.NotNil(t, err)
 }
@@ -95,9 +94,9 @@ func TestDoNewSite_error_force_dir_inside_exists(t *testing.T) {
 func TestDoNewSite_error_force_config_inside_exists(t *testing.T) {
 	basepath := filepath.Join(os.TempDir(), "blog")
 	configPath := filepath.Join(basepath, "config.toml")
-	hugofs.SourceFs = new(afero.MemMapFs)
-	hugofs.SourceFs.MkdirAll(basepath, 777)
-	hugofs.SourceFs.Create(configPath)
+	hugofs.InitMemFs()
+	hugofs.Source().MkdirAll(basepath, 777)
+	hugofs.Source().Create(configPath)
 	err := doNewSite(basepath, true)
 	assert.NotNil(t, err)
 }
diff --git a/commands/server.go b/commands/server.go
index 124541b90..345d2dec6 100644
--- a/commands/server.go
+++ b/commands/server.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -152,7 +152,7 @@ func server(cmd *cobra.Command, args []string) error {
 
 	// Hugo writes the output to memory instead of the disk
 	if !renderToDisk {
-		hugofs.DestinationFS = new(afero.MemMapFs)
+		hugofs.SetDestination(new(afero.MemMapFs))
 		// Rendering to memoryFS, publish to Root regardless of publishDir.
 		viper.Set("PublishDir", "/")
 	}
@@ -191,7 +191,7 @@ func serve(port int) {
 		jww.FEEDBACK.Println("Serving pages from memory")
 	}
 
-	httpFs := afero.NewHttpFs(hugofs.DestinationFS)
+	httpFs := afero.NewHttpFs(hugofs.Destination())
 	fs := filesOnlyFs{httpFs.Dir(helpers.AbsPathify(viper.GetString("PublishDir")))}
 	fileserver := http.FileServer(fs)
 
diff --git a/create/content_test.go b/create/content_test.go
index f0b3de1a0..0ccbd03ea 100644
--- a/create/content_test.go
+++ b/create/content_test.go
@@ -44,19 +44,19 @@ func TestNewContent(t *testing.T) {
 	}
 
 	for i, c := range cases {
-		err = create.NewContent(hugofs.SourceFs, c.kind, c.path)
+		err = create.NewContent(hugofs.Source(), c.kind, c.path)
 		if err != nil {
 			t.Errorf("[%d] NewContent: %s", i, err)
 		}
 
 		fname := filepath.Join(os.TempDir(), "content", filepath.FromSlash(c.path))
-		_, err = hugofs.SourceFs.Stat(fname)
+		_, err = hugofs.Source().Stat(fname)
 		if err != nil {
 			t.Errorf("[%d] Stat: %s", i, err)
 		}
 
 		for _, v := range c.resultStrings {
-			found, err := afero.FileContainsBytes(hugofs.SourceFs, fname, []byte(v))
+			found, err := afero.FileContainsBytes(hugofs.Source(), fname, []byte(v))
 			if err != nil {
 				t.Errorf("[%d] FileContainsBytes: %s", i, err)
 			}
@@ -77,7 +77,7 @@ func initViper() {
 }
 
 func initFs() error {
-	hugofs.SourceFs = new(afero.MemMapFs)
+	hugofs.SetSource(new(afero.MemMapFs))
 	perm := os.FileMode(0755)
 	var err error
 
@@ -89,7 +89,7 @@ func initFs() error {
 	}
 	for _, dir := range dirs {
 		dir = filepath.Join(os.TempDir(), dir)
-		err = hugofs.SourceFs.Mkdir(dir, perm)
+		err = hugofs.Source().Mkdir(dir, perm)
 		if err != nil {
 			return err
 		}
@@ -109,7 +109,7 @@ func initFs() error {
 			content: "+++\n+++\n",
 		},
 	} {
-		f, err := hugofs.SourceFs.Create(v.path)
+		f, err := hugofs.Source().Create(v.path)
 		if err != nil {
 			return err
 		}
diff --git a/docs/content/templates/functions.md b/docs/content/templates/functions.md
index b271e33e1..fe0f2e251 100644
--- a/docs/content/templates/functions.md
+++ b/docs/content/templates/functions.md
@@ -83,7 +83,7 @@ e.g. Pass into "foo.html" a map with the keys "important, content"
 or create a map on the fly to pass into 
 
     {{partial "foo" (dict "important" "Smiles" "content" "You should do more")}}
-    
+
 
 
 ### slice
@@ -336,6 +336,12 @@ e.g.
        {{ .Content }}
     {{ end }}
 
+## Files    
+### readFile
+Reads a file from disk and converts it into a string. Note that the filename must be relative to the current project working dir.
+ So, if you have a file with the name `README.txt` in the root of your project with the content `Hugo Rocks!`:
+ 
+ `{{readFile "README.txt"}}` → `"Hugo Rocks!"`
 
 ## Math
 
diff --git a/helpers/pygments.go b/helpers/pygments.go
index fe14ad49f..637f61b19 100644
--- a/helpers/pygments.go
+++ b/helpers/pygments.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -60,7 +60,7 @@ func Highlight(code, lang, optsStr string) string {
 	io.WriteString(hash, lang)
 	io.WriteString(hash, options)
 
-	fs := hugofs.OsFs
+	fs := hugofs.Os()
 
 	cacheDir := viper.GetString("CacheDir")
 	var cachefile string
diff --git a/hugofs/fs.go b/hugofs/fs.go
index 7807bf935..a3cb55ea1 100644
--- a/hugofs/fs.go
+++ b/hugofs/fs.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -13,8 +13,81 @@
 
 package hugofs
 
-import "github.com/spf13/afero"
+import (
+	"github.com/spf13/afero"
+	"github.com/spf13/viper"
+)
 
-var SourceFs afero.Fs = new(afero.OsFs)
-var DestinationFS afero.Fs = new(afero.OsFs)
-var OsFs afero.Fs = new(afero.OsFs)
+var (
+	sourceFs      afero.Fs
+	destinationFs afero.Fs
+	osFs          afero.Fs = &afero.OsFs{}
+	workingDirFs  *afero.BasePathFs
+)
+
+// Source returns Hugo's source file system.
+func Source() afero.Fs {
+	return sourceFs
+}
+
+// SetSource sets Hugo's source file system
+// and re-initializes dependent file systems.
+func SetSource(fs afero.Fs) {
+	sourceFs = fs
+	initSourceDependencies()
+}
+
+// Destination returns Hugo's destionation file system.
+func Destination() afero.Fs {
+	return destinationFs
+}
+
+// SetDestination sets Hugo's destionation file system
+func SetDestination(fs afero.Fs) {
+	destinationFs = fs
+}
+
+// Os returns an OS file system.
+func Os() afero.Fs {
+	return osFs
+}
+
+// WorkingDir returns a read-only file system
+// restricted to the project working dir.
+func WorkingDir() *afero.BasePathFs {
+	return workingDirFs
+}
+
+// InitFs initializes with the OS file system
+// as source and destination file systems.
+func InitDefaultFs() {
+	InitFs(&afero.OsFs{})
+}
+
+// InitMemFs initializes with a MemMapFs as source and destination file systems.
+// Useful for testing.
+func InitMemFs() {
+	InitFs(&afero.MemMapFs{})
+}
+
+// InitFs initializes with the given file system
+// as source and destination file systems.
+func InitFs(fs afero.Fs) {
+	sourceFs = fs
+	destinationFs = fs
+
+	initSourceDependencies()
+}
+
+func initSourceDependencies() {
+	workingDir := viper.GetString("WorkingDir")
+
+	if workingDir != "" {
+		workingDirFs = afero.NewBasePathFs(afero.NewReadOnlyFs(sourceFs), workingDir).(*afero.BasePathFs)
+	}
+
+}
+
+func init() {
+	InitDefaultFs()
+}
diff --git a/hugofs/fs_test.go b/hugofs/fs_test.go
new file mode 100644
index 000000000..06d63a78f
--- /dev/null
+++ b/hugofs/fs_test.go
@@ -0,0 +1,72 @@
+// Copyright 2016 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 hugofs
+
+import (
+	"github.com/spf13/afero"
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestInitDefault(t *testing.T) {
+	viper.Reset()
+	defer viper.Reset()
+
+	InitDefaultFs()
+
+	assert.IsType(t, new(afero.OsFs), Source())
+	assert.IsType(t, new(afero.OsFs), Destination())
+	assert.IsType(t, new(afero.OsFs), Os())
+	assert.Nil(t, WorkingDir())
+}
+
+func TestInitMemFs(t *testing.T) {
+	viper.Reset()
+	defer viper.Reset()
+
+	InitMemFs()
+
+	assert.IsType(t, new(afero.MemMapFs), Source())
+	assert.IsType(t, new(afero.MemMapFs), Destination())
+	assert.IsType(t, new(afero.OsFs), Os())
+	assert.Nil(t, WorkingDir())
+}
+
+func TestSetSource(t *testing.T) {
+
+	InitMemFs()
+
+	SetSource(new(afero.OsFs))
+	assert.IsType(t, new(afero.OsFs), Source())
+}
+
+func TestSetDestination(t *testing.T) {
+
+	InitMemFs()
+
+	SetDestination(new(afero.OsFs))
+	assert.IsType(t, new(afero.OsFs), Destination())
+}
+
+func TestWorkingDir(t *testing.T) {
+	viper.Reset()
+	defer viper.Reset()
+
+	viper.Set("WorkingDir", "/a/b/")
+
+	InitMemFs()
+
+	assert.IsType(t, new(afero.BasePathFs), WorkingDir())
+}
diff --git a/hugolib/handler_test.go b/hugolib/handler_test.go
index df5b970c9..29b1161e4 100644
--- a/hugolib/handler_test.go
+++ b/hugolib/handler_test.go
@@ -17,7 +17,6 @@ import (
 	"path/filepath"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/helpers"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
@@ -29,7 +28,7 @@ func TestDefaultHandler(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("sect/doc1.html"), []byte("---\nmarkup: markdown\n---\n# title\nsome *content*")},
 		{filepath.FromSlash("sect/doc2.html"), []byte("<!doctype html><html><body>more content</body></html>")},
@@ -75,7 +74,7 @@ func TestDefaultHandler(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.doc)
+		file, err := hugofs.Destination().Open(test.doc)
 		if err != nil {
 			t.Fatalf("Did not find %s in target.", test.doc)
 		}
diff --git a/hugolib/menu_test.go b/hugolib/menu_test.go
index 609a87d01..aaa172ebf 100644
--- a/hugolib/menu_test.go
+++ b/hugolib/menu_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -22,7 +22,6 @@ import (
 
 	"github.com/BurntSushi/toml"
 	"github.com/kr/pretty"
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
 	"github.com/spf13/viper"
@@ -684,7 +683,7 @@ func setupMenuTests(t *testing.T, pageSources []source.ByteSource) *Site {
 }
 
 func createTestSite(pageSources []source.ByteSource) *Site {
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	s := &Site{
 		Source: &source.InMemorySource{ByteSource: pageSources},
diff --git a/hugolib/page.go b/hugolib/page.go
index a2b4d3119..3d1b48738 100644
--- a/hugolib/page.go
+++ b/hugolib/page.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -890,9 +890,9 @@ func (p *Page) saveSource(by []byte, inpath string, safe bool) (err error) {
 	jww.INFO.Println("creating", inpath)
 
 	if safe {
-		err = helpers.SafeWriteToDisk(inpath, bytes.NewReader(by), hugofs.SourceFs)
+		err = helpers.SafeWriteToDisk(inpath, bytes.NewReader(by), hugofs.Source())
 	} else {
-		err = helpers.WriteToDisk(inpath, bytes.NewReader(by), hugofs.SourceFs)
+		err = helpers.WriteToDisk(inpath, bytes.NewReader(by), hugofs.Source())
 	}
 	if err != nil {
 		return
diff --git a/hugolib/robotstxt_test.go b/hugolib/robotstxt_test.go
index 31f89b847..b0a843a7e 100644
--- a/hugolib/robotstxt_test.go
+++ b/hugolib/robotstxt_test.go
@@ -1,10 +1,22 @@
+// Copyright 2016 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 (
 	"bytes"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/helpers"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
@@ -21,7 +33,7 @@ func TestRobotsTXTOutput(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	viper.Set("baseurl", "http://auth/bub/")
 
@@ -53,7 +65,7 @@ func TestRobotsTXTOutput(t *testing.T) {
 		t.Fatalf("Unable to RenderRobotsTXT :%s", err)
 	}
 
-	robotsFile, err := hugofs.DestinationFS.Open("robots.txt")
+	robotsFile, err := hugofs.Destination().Open("robots.txt")
 
 	if err != nil {
 		t.Fatalf("Unable to locate: robots.txt")
diff --git a/hugolib/rss_test.go b/hugolib/rss_test.go
index b8a16665f..e42202a5b 100644
--- a/hugolib/rss_test.go
+++ b/hugolib/rss_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -17,7 +17,6 @@ import (
 	"bytes"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/helpers"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
@@ -53,7 +52,7 @@ func TestRSSOutput(t *testing.T) {
 	viper.Set("baseurl", "http://auth/bub/")
 	viper.Set("RSSUri", rssURI)
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	s := &Site{
 		Source: &source.InMemorySource{ByteSource: WEIGHTED_SOURCES},
 	}
@@ -72,7 +71,7 @@ func TestRSSOutput(t *testing.T) {
 		t.Fatalf("Unable to RenderHomePage: %s", err)
 	}
 
-	file, err := hugofs.DestinationFS.Open(rssURI)
+	file, err := hugofs.Destination().Open(rssURI)
 
 	if err != nil {
 		t.Fatalf("Unable to locate: %s", rssURI)
diff --git a/hugolib/shortcode_test.go b/hugolib/shortcode_test.go
index 833cdae99..ab764b845 100644
--- a/hugolib/shortcode_test.go
+++ b/hugolib/shortcode_test.go
@@ -487,7 +487,7 @@ e`,
 	createAndRenderPages(t, s)
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.outFile)
+		file, err := hugofs.Destination().Open(test.outFile)
 
 		if err != nil {
 			t.Fatalf("Did not find %s in target: %s", test.outFile, err)
diff --git a/hugolib/site.go b/hugolib/site.go
index b1c5090f9..192628051 100644
--- a/hugolib/site.go
+++ b/hugolib/site.go
@@ -529,7 +529,7 @@ func (s *Site) ReBuild(events []fsnotify.Event) error {
 		// it's been updated
 		if ev.Op&fsnotify.Rename == fsnotify.Rename {
 			// If the file is still on disk, it's only been updated, if it's not, it's been moved
-			if ex, err := afero.Exists(hugofs.SourceFs, ev.Name); !ex || err != nil {
+			if ex, err := afero.Exists(hugofs.Source(), ev.Name); !ex || err != nil {
 				path, _ := helpers.GetRelativePath(ev.Name, s.absContentDir())
 				s.RemovePageByPath(path)
 				continue
@@ -852,7 +852,7 @@ func (s *Site) absPublishDir() string {
 }
 
 func (s *Site) checkDirectories() (err error) {
-	if b, _ := helpers.DirExists(s.absContentDir(), hugofs.SourceFs); !b {
+	if b, _ := helpers.DirExists(s.absContentDir(), hugofs.Source()); !b {
 		return fmt.Errorf("No source directory found, expecting to find it at " + s.absContentDir())
 	}
 	return
diff --git a/hugolib/site_test.go b/hugolib/site_test.go
index d96db4323..1173d0f3d 100644
--- a/hugolib/site_test.go
+++ b/hugolib/site_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -25,7 +25,6 @@ import (
 
 	"bitbucket.org/pkg/inflect"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/helpers"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
@@ -200,7 +199,7 @@ func TestRenderThingOrDefault(t *testing.T) {
 		{false, TEMPLATE_FUNC, HTML("simple-template")},
 	}
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	for i, test := range tests {
 
@@ -226,7 +225,7 @@ func TestRenderThingOrDefault(t *testing.T) {
 			t.Errorf("Unable to render html: %s", err)
 		}
 
-		file, err := hugofs.DestinationFS.Open(filepath.FromSlash("out/index.html"))
+		file, err := hugofs.Destination().Open(filepath.FromSlash("out/index.html"))
 		if err != nil {
 			t.Errorf("Unable to open html: %s", err)
 		}
@@ -240,7 +239,7 @@ func TestDraftAndFutureRender(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("sect/doc1.md"), []byte("---\ntitle: doc1\ndraft: true\npublishdate: \"2414-05-29\"\n---\n# doc1\n*some content*")},
 		{filepath.FromSlash("sect/doc2.md"), []byte("---\ntitle: doc2\ndraft: true\npublishdate: \"2012-05-29\"\n---\n# doc2\n*some content*")},
@@ -299,7 +298,7 @@ func TestDraftAndFutureRender(t *testing.T) {
 
 // Issue #957
 func TestCrossrefs(t *testing.T) {
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	for _, uglyURLs := range []bool{true, false} {
 		for _, relative := range []bool{true, false} {
 			doTestCrossrefs(t, relative, uglyURLs)
@@ -374,7 +373,7 @@ THE END.`, refShortcode))},
 	}
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.doc)
+		file, err := hugofs.Destination().Open(test.doc)
 
 		if err != nil {
 			t.Fatalf("Did not find %s in target: %s", test.doc, err)
@@ -392,7 +391,7 @@ THE END.`, refShortcode))},
 // Issue #939
 // Issue #1923
 func TestShouldAlwaysHaveUglyURLs(t *testing.T) {
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	for _, uglyURLs := range []bool{true, false} {
 		doTestShouldAlwaysHaveUglyURLs(t, uglyURLs)
 	}
@@ -462,7 +461,7 @@ func doTestShouldAlwaysHaveUglyURLs(t *testing.T, uglyURLs bool) {
 	}
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.doc)
+		file, err := hugofs.Destination().Open(test.doc)
 		if err != nil {
 			t.Fatalf("Did not find %s in target: %s", test.doc, err)
 		}
@@ -489,7 +488,7 @@ func TestSectionNaming(t *testing.T) {
 }
 
 func doTestSectionNaming(t *testing.T, canonify, uglify, pluralize bool) {
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	viper.Reset()
 	defer viper.Reset()
 	viper.Set("baseurl", "http://auth/sub/")
@@ -539,7 +538,7 @@ func doTestSectionNaming(t *testing.T, canonify, uglify, pluralize bool) {
 	}
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.doc)
+		file, err := hugofs.Destination().Open(test.doc)
 		if err != nil {
 			t.Fatalf("Did not find %s in target: %s", test.doc, err)
 		}
@@ -560,7 +559,7 @@ func TestSkipRender(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("sect/doc1.html"), []byte("---\nmarkup: markdown\n---\n# title\nsome *content*")},
 		{filepath.FromSlash("sect/doc2.html"), []byte("<!doctype html><html><body>more content</body></html>")},
@@ -605,7 +604,7 @@ func TestSkipRender(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		file, err := hugofs.DestinationFS.Open(test.doc)
+		file, err := hugofs.Destination().Open(test.doc)
 		if err != nil {
 			t.Fatalf("Did not find %s in target.", test.doc)
 		}
@@ -624,7 +623,7 @@ func TestAbsURLify(t *testing.T) {
 
 	viper.Set("DefaultExtension", "html")
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("sect/doc1.html"), []byte("<!doctype html><html><head></head><body><a href=\"#frag1\">link</a></body></html>")},
 		{filepath.FromSlash("content/blue/doc2.html"), []byte("---\nf: t\n---\n<!doctype html><html><body>more content</body></html>")},
@@ -662,7 +661,7 @@ func TestAbsURLify(t *testing.T) {
 
 		for _, test := range tests {
 
-			file, err := hugofs.DestinationFS.Open(filepath.FromSlash(test.file))
+			file, err := hugofs.Destination().Open(filepath.FromSlash(test.file))
 			if err != nil {
 				t.Fatalf("Unable to locate rendered content: %s", test.file)
 			}
@@ -730,7 +729,7 @@ func TestOrderedPages(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	viper.Set("baseurl", "http://auth/bub")
 	s := &Site{
@@ -804,7 +803,7 @@ func TestGroupedPages(t *testing.T) {
 		}
 	}()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	viper.Set("baseurl", "http://auth/bub")
 	s := &Site{
@@ -984,7 +983,7 @@ func TestWeightedTaxonomies(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("sect/doc1.md"), PAGE_WITH_WEIGHTED_TAXONOMIES_1},
 		{filepath.FromSlash("sect/doc2.md"), PAGE_WITH_WEIGHTED_TAXONOMIES_2},
@@ -1039,7 +1038,7 @@ func findPage(site *Site, f string) *Page {
 }
 
 func setupLinkingMockSite(t *testing.T) *Site {
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 	sources := []source.ByteSource{
 		{filepath.FromSlash("index.md"), []byte("")},
 		{filepath.FromSlash("rootfile.md"), []byte("")},
diff --git a/hugolib/site_url_test.go b/hugolib/site_url_test.go
index 2bccd99ae..c4c918c88 100644
--- a/hugolib/site_url_test.go
+++ b/hugolib/site_url_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -19,7 +19,6 @@ import (
 
 	"html/template"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
 	"github.com/spf13/hugo/target"
@@ -88,7 +87,7 @@ func TestPageCount(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	viper.Set("uglyurls", false)
 	viper.Set("paginate", 10)
@@ -113,7 +112,7 @@ func TestPageCount(t *testing.T) {
 		t.Errorf("Unable to render site lists: %s", err)
 	}
 
-	_, err := hugofs.DestinationFS.Open("blue")
+	_, err := hugofs.Destination().Open("blue")
 	if err != nil {
 		t.Errorf("No indexed rendered.")
 	}
@@ -129,7 +128,7 @@ func TestPageCount(t *testing.T) {
 		"sd3/index.html",
 		"sd4.html",
 	} {
-		if _, err := hugofs.DestinationFS.Open(filepath.FromSlash(s)); err != nil {
+		if _, err := hugofs.Destination().Open(filepath.FromSlash(s)); err != nil {
 			t.Errorf("No alias rendered: %s", s)
 		}
 	}
diff --git a/hugolib/sitemap_test.go b/hugolib/sitemap_test.go
index 34f2d3477..3f10bbcdd 100644
--- a/hugolib/sitemap_test.go
+++ b/hugolib/sitemap_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -17,7 +17,6 @@ import (
 	"bytes"
 	"testing"
 
-	"github.com/spf13/afero"
 	"github.com/spf13/hugo/helpers"
 	"github.com/spf13/hugo/hugofs"
 	"github.com/spf13/hugo/source"
@@ -40,7 +39,7 @@ func TestSitemapOutput(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
-	hugofs.DestinationFS = new(afero.MemMapFs)
+	hugofs.InitMemFs()
 
 	viper.Set("baseurl", "http://auth/bub/")
 
@@ -72,7 +71,7 @@ func TestSitemapOutput(t *testing.T) {
 		t.Fatalf("Unable to RenderRobotsTXT :%s", err)
 	}
 
-	sitemapFile, err := hugofs.DestinationFS.Open("sitemap.xml")
+	sitemapFile, err := hugofs.Destination().Open("sitemap.xml")
 
 	if err != nil {
 		t.Fatalf("Unable to locate: sitemap.xml")
diff --git a/source/filesystem.go b/source/filesystem.go
index 053081a7a..0ce5808d1 100644
--- a/source/filesystem.go
+++ b/source/filesystem.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -93,7 +93,7 @@ func (f *Filesystem) captureFiles() {
 		return err
 	}
 
-	err := helpers.SymbolicWalk(hugofs.SourceFs, f.Base, walker)
+	err := helpers.SymbolicWalk(hugofs.Source(), f.Base, walker)
 
 	if err != nil {
 		jww.ERROR.Println(err)
diff --git a/target/file.go b/target/file.go
index 41fa00255..740741bba 100644
--- a/target/file.go
+++ b/target/file.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -49,7 +49,7 @@ func (fs *Filesystem) Publish(path string, r io.Reader) (err error) {
 		return
 	}
 
-	return helpers.WriteToDisk(translated, r, hugofs.DestinationFS)
+	return helpers.WriteToDisk(translated, r, hugofs.Destination())
 }
 
 func (fs *Filesystem) Translate(src string) (dest string, err error) {
diff --git a/target/htmlredirect.go b/target/htmlredirect.go
index b5b47a889..1e2abec40 100644
--- a/target/htmlredirect.go
+++ b/target/htmlredirect.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -144,5 +144,5 @@ func (h *HTMLRedirectAlias) Publish(path string, permalink string) (err error) {
 		return
 	}
 
-	return helpers.WriteToDisk(path, buffer, hugofs.DestinationFS)
+	return helpers.WriteToDisk(path, buffer, hugofs.Destination())
 }
diff --git a/target/page.go b/target/page.go
index 9e7efdb61..d67d678f9 100644
--- a/target/page.go
+++ b/target/page.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -41,7 +41,7 @@ func (pp *PagePub) Publish(path string, r io.Reader) (err error) {
 		return
 	}
 
-	return helpers.WriteToDisk(translated, r, hugofs.DestinationFS)
+	return helpers.WriteToDisk(translated, r, hugofs.Destination())
 }
 
 func (pp *PagePub) Translate(src string) (dest string, err error) {
diff --git a/tpl/template.go b/tpl/template.go
index 9266fc8d4..7fad95912 100644
--- a/tpl/template.go
+++ b/tpl/template.go
@@ -235,7 +235,7 @@ func (t *GoHTMLTemplate) AddTemplateFileWithMaster(name, overlayFilename, master
 	masterTpl := t.Lookup(masterFilename)
 
 	if masterTpl == nil {
-		b, err := afero.ReadFile(hugofs.SourceFs, masterFilename)
+		b, err := afero.ReadFile(hugofs.Source(), masterFilename)
 		if err != nil {
 			return err
 		}
@@ -248,7 +248,7 @@ func (t *GoHTMLTemplate) AddTemplateFileWithMaster(name, overlayFilename, master
 		}
 	}
 
-	b, err := afero.ReadFile(hugofs.SourceFs, overlayFilename)
+	b, err := afero.ReadFile(hugofs.Source(), overlayFilename)
 	if err != nil {
 		return err
 	}
@@ -309,14 +309,14 @@ func (t *GoHTMLTemplate) AddTemplateFile(name, baseTemplatePath, path string) er
 		}
 	case ".ace":
 		var innerContent, baseContent []byte
-		innerContent, err := afero.ReadFile(hugofs.SourceFs, path)
+		innerContent, err := afero.ReadFile(hugofs.Source(), path)
 
 		if err != nil {
 			return err
 		}
 
 		if baseTemplatePath != "" {
-			baseContent, err = afero.ReadFile(hugofs.SourceFs, baseTemplatePath)
+			baseContent, err = afero.ReadFile(hugofs.Source(), baseTemplatePath)
 			if err != nil {
 				return err
 			}
@@ -329,7 +329,7 @@ func (t *GoHTMLTemplate) AddTemplateFile(name, baseTemplatePath, path string) er
 			return t.AddTemplateFileWithMaster(name, path, baseTemplatePath)
 		}
 
-		b, err := afero.ReadFile(hugofs.SourceFs, path)
+		b, err := afero.ReadFile(hugofs.Source(), path)
 
 		if err != nil {
 			return err
@@ -414,7 +414,7 @@ func (t *GoHTMLTemplate) loadTemplates(absPath string, prefix string) {
 
 				// This may be a view that shouldn't have base template
 				// Have to look inside it to make sure
-				needsBase, err := helpers.FileContainsAny(path, innerMarkers, hugofs.OsFs)
+				needsBase, err := helpers.FileContainsAny(path, innerMarkers, hugofs.Os())
 				if err != nil {
 					return err
 				}
@@ -442,7 +442,7 @@ func (t *GoHTMLTemplate) loadTemplates(absPath string, prefix string) {
 					}
 
 					for _, pathToCheck := range pathsToCheck {
-						if ok, err := helpers.Exists(pathToCheck, hugofs.OsFs); err == nil && ok {
+						if ok, err := helpers.Exists(pathToCheck, hugofs.Os()); err == nil && ok {
 							baseTemplatePath = pathToCheck
 							break
 						}
diff --git a/tpl/template_funcs.go b/tpl/template_funcs.go
index 5fb496c14..8abd70b8c 100644
--- a/tpl/template_funcs.go
+++ b/tpl/template_funcs.go
@@ -24,6 +24,8 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"github.com/spf13/afero"
+	"github.com/spf13/hugo/hugofs"
 	"html"
 	"html/template"
 	"math/rand"
@@ -1467,6 +1469,38 @@ func index(item interface{}, indices ...interface{}) (interface{}, error) {
 	return v.Interface(), nil
 }
 
+// readFile reads the file named by filename relative to the given basepath
+// and returns the contents as a string.
+// There is a upper size limit set at 1 megabytes.
+func readFile(fs *afero.BasePathFs, filename string) (string, error) {
+	if filename == "" {
+		return "", errors.New("readFile needs a filename")
+	}
+
+	if info, err := fs.Stat(filename); err == nil {
+		if info.Size() > 1000000 {
+			return "", fmt.Errorf("File %q is too big", filename)
+		}
+	} else {
+		return "", err
+	}
+	b, err := afero.ReadFile(fs, filename)
+
+	if err != nil {
+		return "", err
+	}
+
+	return string(b), nil
+}
+
+// readFileFromWorkingDir reads the file named by filename relative to the
+// configured WorkingDir.
+// It returns the contents as a string.
+// There is a upper size limit set at 1 megabytes.
+func readFileFromWorkingDir(i interface{}) (string, error) {
+	return readFile(hugofs.WorkingDir(), cast.ToString(i))
+}
+
 // safeHTMLAttr returns a given string as html/template HTMLAttr content.
 //
 // safeHTMLAttr is currently disabled, pending further discussion
@@ -1689,6 +1723,7 @@ func init() {
 		"plainify":     plainify,
 		"pluralize":    pluralize,
 		"readDir":      readDir,
+		"readFile":     readFileFromWorkingDir,
 		"ref":          ref,
 		"relURL":       func(a string) template.HTML { return template.HTML(helpers.RelURL(a)) },
 		"relref":       relRef,
diff --git a/tpl/template_funcs_test.go b/tpl/template_funcs_test.go
index 77cd52a33..efb583867 100644
--- a/tpl/template_funcs_test.go
+++ b/tpl/template_funcs_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -18,18 +18,20 @@ import (
 	"encoding/base64"
 	"errors"
 	"fmt"
+	"github.com/spf13/afero"
+	"github.com/spf13/cast"
+	"github.com/spf13/hugo/hugofs"
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/assert"
 	"html/template"
 	"math/rand"
 	"path"
+	"path/filepath"
 	"reflect"
 	"runtime"
 	"strings"
 	"testing"
 	"time"
-
-	"github.com/spf13/cast"
-	"github.com/spf13/viper"
-	"github.com/stretchr/testify/assert"
 )
 
 type tstNoStringer struct {
@@ -63,6 +65,15 @@ func TestFuncsInTemplate(t *testing.T) {
 	viper.Reset()
 	defer viper.Reset()
 
+	workingDir := "/home/hugo"
+
+	viper.Set("WorkingDir", workingDir)
+
+	fs := &afero.MemMapFs{}
+	hugofs.InitFs(fs)
+
+	afero.WriteFile(fs, filepath.Join(workingDir, "README.txt"), []byte("Hugo Rocks!"), 0755)
+
 	// Add the examples from the docs: As a smoke test and to make sure the examples work.
 	// TODO(bep): docs: fix title example
 	in :=
@@ -109,6 +120,7 @@ safeCSS: {{ "Bat&Man" | safeCSS | safeCSS }}
 safeURL: {{ "http://gohugo.io" | safeURL | safeURL }}
 safeJS: {{ "(1*2)" | safeJS | safeJS }}
 plainify: {{ plainify  "Hello <strong>world</strong>, gophers!" }}
+readFile: {{ readFile "README.txt" }}
 `
 	expected := `chomp: <p>Blockhead</p>
 dateFormat: Wednesday, Jan 21, 2015
@@ -153,6 +165,7 @@ safeCSS: Bat&amp;Man
 safeURL: http://gohugo.io
 safeJS: (1*2)
 plainify: Hello world, gophers!
+readFile: Hugo Rocks!
 `
 
 	var b bytes.Buffer
@@ -2182,3 +2195,44 @@ func TestSHA1(t *testing.T) {
 		}
 	}
 }
+
+func TestReadFile(t *testing.T) {
+	viper.Reset()
+	defer viper.Reset()
+
+	workingDir := "/home/hugo"
+
+	viper.Set("WorkingDir", workingDir)
+
+	fs := &afero.MemMapFs{}
+	hugofs.InitFs(fs)
+
+	afero.WriteFile(fs, filepath.Join(workingDir, "/f/f1.txt"), []byte("f1-content"), 0755)
+	afero.WriteFile(fs, filepath.Join("/home", "f2.txt"), []byte("f2-content"), 0755)
+
+	for i, this := range []struct {
+		filename string
+		expect   interface{}
+	}{
+		{"", false},
+		{"b", false},
+		{filepath.FromSlash("/f/f1.txt"), "f1-content"},
+		{filepath.FromSlash("f/f1.txt"), "f1-content"},
+		{filepath.FromSlash("../f2.txt"), false},
+	} {
+		result, err := readFileFromWorkingDir(this.filename)
+		if b, ok := this.expect.(bool); ok && !b {
+			if err == nil {
+				t.Errorf("[%d] readFile didn't return an expected error", i)
+			}
+		} else {
+			if err != nil {
+				t.Errorf("[%d] readFile failed: %s", i, err)
+				continue
+			}
+			if result != this.expect {
+				t.Errorf("[%d] readFile got %q but expected %q", i, result, this.expect)
+			}
+		}
+	}
+}
diff --git a/tpl/template_resources.go b/tpl/template_resources.go
index 1c0655d2c..0d0ea8332 100644
--- a/tpl/template_resources.go
+++ b/tpl/template_resources.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -177,9 +177,9 @@ func resGetResource(url string) ([]byte, error) {
 		return nil, nil
 	}
 	if strings.Contains(url, "://") {
-		return resGetRemote(url, hugofs.SourceFs, http.DefaultClient)
+		return resGetRemote(url, hugofs.Source(), http.DefaultClient)
 	}
-	return resGetLocal(url, hugofs.SourceFs)
+	return resGetLocal(url, hugofs.Source())
 }
 
 // getJSON expects one or n-parts of a URL to a resource which can either be a local or a remote one.
@@ -201,7 +201,7 @@ func getJSON(urlParts ...string) interface{} {
 			jww.ERROR.Printf("Cannot read json from resource %s with error message %s", url, err)
 			jww.ERROR.Printf("Retry #%d for %s and sleeping for %s", i, url, resSleep)
 			time.Sleep(resSleep)
-			resDeleteCache(url, hugofs.SourceFs)
+			resDeleteCache(url, hugofs.Source())
 			continue
 		}
 		break
@@ -234,7 +234,7 @@ func getCSV(sep string, urlParts ...string) [][]string {
 	var clearCacheSleep = func(i int, u string) {
 		jww.ERROR.Printf("Retry #%d for %s and sleeping for %s", i, url, resSleep)
 		time.Sleep(resSleep)
-		resDeleteCache(url, hugofs.SourceFs)
+		resDeleteCache(url, hugofs.Source())
 	}
 
 	for i := 0; i <= resRetries; i++ {
diff --git a/tpl/template_resources_test.go b/tpl/template_resources_test.go
index 8e3a9d1d0..d091595b0 100644
--- a/tpl/template_resources_test.go
+++ b/tpl/template_resources_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -214,7 +214,7 @@ type wd struct {
 
 func testRetryWhenDone() wd {
 	cd := viper.GetString("CacheDir")
-	viper.Set("CacheDir", helpers.GetTempDir("", hugofs.SourceFs))
+	viper.Set("CacheDir", helpers.GetTempDir("", hugofs.Source()))
 	var tmpSleep time.Duration
 	tmpSleep, resSleep = resSleep, time.Millisecond
 	return wd{func() {
diff --git a/tpl/template_test.go b/tpl/template_test.go
index 9649a8fa8..c96b8c87c 100644
--- a/tpl/template_test.go
+++ b/tpl/template_test.go
@@ -1,4 +1,4 @@
-// Copyright 2015 The Hugo Authors. All rights reserved.
+// Copyright 2016 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.
@@ -123,17 +123,17 @@ func TestAddTemplateFileWithMaster(t *testing.T) {
 		{`tpl`, `{{.0.E}}`, 0, false},
 	} {
 
-		hugofs.SourceFs = afero.NewMemMapFs()
+		hugofs.InitMemFs()
 		templ := New()
 		overlayTplName := "ot"
 		masterTplName := "mt"
 		finalTplName := "tp"
 
 		if this.writeSkipper != 1 {
-			afero.WriteFile(hugofs.SourceFs, masterTplName, []byte(this.masterTplContent), 0644)
+			afero.WriteFile(hugofs.Source(), masterTplName, []byte(this.masterTplContent), 0644)
 		}
 		if this.writeSkipper != 2 {
-			afero.WriteFile(hugofs.SourceFs, overlayTplName, []byte(this.overlayTplContent), 0644)
+			afero.WriteFile(hugofs.Source(), overlayTplName, []byte(this.overlayTplContent), 0644)
 		}
 
 		err := templ.AddTemplateFileWithMaster(finalTplName, overlayTplName, masterTplName)