Replace static compilation with package staticdir

The contents of static.go have been removed and replaced with the more
flexible package staticdir, which will be more suitable to our future
needs. This will allow us to fix @lukevers's new issue #188 much more
easily by implementing our own CopyFunc.

I had originally planned to delete static.go entirely, but I believe it
makes more sense to keep it there with CompileStatic and whatever new
CopyFunc we write.

Author: alexander-bauer

static.go

@@ -4,21 +4,12 @@ package main
 // Dylan Whichard, and contributors; (GPLv3) see LICENSE or doc.go
 
 import (
-	"html/template"
-	"io"
+	"github.com/SashaCrofter/staticdir"
 	"io/ioutil"
-	"os"
-	"path"
-	"strings"
 )
 
-// CompileStatic traverses a directory, gathering a list of all
-// files. It then performs actions based on their filenames, and
-// copies them to a temporary directory. It returns the name of the
-// temporary directory.
-//
-// Files with the ".tmpl" extention are run through 'html/template'
-// engine with the data argument being the supplied *Config.
+// CompileStatic uses staticdir to translate a resource directory into
+// static content. It returns the directory into which it copies.
 func CompileStatic(dir string, conf *Config) (tmpdir string, err error) {
 	// Create a directory in the OS's tempdir, (`/tmp`), with the
 	// prefix being the name of the map.
@@ -27,144 +18,13 @@ func CompileStatic(dir string, conf *Config) (tmpdir string, err error) {
 		return
 	}
 
-	// Next, get a slice of all files in the directory, and any in its
-	// subdirectories (recursively).
-	files := make([]string, 0)
-	err = crawlDirectories(&files, tmpdir, dir)
-	if err != nil {
-		return
-	}
-
-	// Now, process the files one at a time, writing the result to
-	// `<tmpdir>/path/to/file`. The path is the path to the file
-	// within the given dir.
-	err = processFiles(files, conf, tmpdir, dir)
-	if err != nil {
-		return
-	}
-
-	return
-}
-
-// processFiles uses the file extension(s) to transform each file,
-// placing the result in the outdir with the same path, with the
-// prefix sliced off from the filename. Templates are executed with
-// conf as data.It will panic if any of the files are shorter than
-// len(prefix).
-func processFiles(files []string, conf *Config,
-	outdir, prefix string) error {
-
-	tmpldata := struct {
+	// Create a translator via package staticdir.
+	t := staticdir.New(dir, tmpdir)
+	t.CopyFunc = staticdir.TemplateCopy
+	t.CopyData = struct {
 		*Config
 		Version string
 	}{conf, Version}
 
-	for _, filename := range files {
-		// Now, process based on file extension.
-		switch path.Ext(filename) {
-		case ".tmpl":
-			// First, open the outfile. html/template handles the
-			// infile. Note that it strips out the ".tmpl" extension.
-			out, err := os.Create(path.Join(outdir,
-				filename[len(prefix):len(filename)-5]))
-			if err != nil {
-				return err
-			}
-			defer out.Close()
-
-			// Next, parse the template from the file.
-			t, err := template.ParseFiles(filename)
-			if err != nil {
-				return err
-			}
-
-			// Finally, write it to the file using conf as data.
-			err = t.Execute(out, tmpldata)
-			if err != nil {
-				return err
-			}
-		default:
-			// Begin by opening the in file and creating the out file.
-			in, err := os.Open(filename)
-			if err != nil {
-				return err
-			}
-			defer in.Close()
-			out, err := os.Create(path.Join(outdir, filename[len(prefix):]))
-			if err != nil {
-				return err
-			}
-			defer out.Close()
-
-			// If the file extension was not recognized, just copy it
-			// directly.
-			_, err = io.Copy(out, in)
-			if err != nil {
-				return err
-			}
-		}
-	}
-	return nil
-}
-
-// crawlDirectories uses os.Readdir() on the given dir to retrieve a
-// list of os.FileInfo types. It goes through that list, sorting them
-// by file extension and inserting them in the given list of files. If
-// it encounters a directory, it creates that directory under the
-// tmpdir, and recursively calls itself until it has a listed every
-// file.
-func crawlDirectories(files *[]string, tmpdir, dir string) (err error) {
-	// First, open the file so that we can use Readdir().
-	f, err := os.Open(dir)
-	if err != nil {
-		return
-	}
-
-	// Next, get a list of os.FileInfo types, and close the file as
-	// soon as possible.
-	fis, err := f.Readdir(0)
-	f.Close()
-	if err != nil {
-		return
-	}
-
-	// Initialize a slice for new filenames with length zero, and
-	// capacity len(fi). That way, actual files can be appended easily
-	// without leaving blanks.
-	newFiles := make([]string, 0, len(fis))
-
-	// Loop through the slice of os.FileInfo types and check if each
-	// is a directory. If it isn't, append it to newFiles. If it is,
-	// call crawlDirectories() on it again.
-	for _, fi := range fis {
-		if len(fi.Name()) > 0 &&
-			(strings.HasPrefix(fi.Name(), ".") ||
-				strings.HasPrefix(fi.Name(), "#") ||
-				strings.HasSuffix(fi.Name(), "~")) {
-			// Make sure not to include files that start with . or #
-			// Also make sure not to include files that end in ~
-		} else if !fi.IsDir() {
-			// If a file...
-			newFiles = append(newFiles, path.Join(dir, fi.Name()))
-		} else {
-			// If a directory...
-			newdir := path.Join(tmpdir, fi.Name())
-			err = os.Mkdir(newdir, 0777)
-			if err != nil {
-				return
-			}
-			// Here, we tell the next call that the tmpdir is the one
-			// we just created in our tmpdir, and the directory to
-			// crawl is the one we just discovered.
-			err = crawlDirectories(files,
-				newdir, path.Join(dir, fi.Name()))
-			if err != nil {
-				return
-			}
-		}
-	}
-
-	// Finally, append newFiles to the target slice.
-	*files = append(*files, newFiles...)
-	return
+	return tmpdir, t.Translate()
 }