Added facilities to pipe file data into stdin.

README

@@ -51,8 +51,14 @@ generated go file.
 
  You can now simply include the new .go file in your program and call
  gophercolor_png() to get the uncompressed image data.
-
  See the testdata directory for example input and output.
 
+ Aternatively, you can pipe the input file data into stdin. bindata will then
+ spit out the generated Go code to stdout. This does require explicitly naming
+ the desired function name, as it can not be inferred from the input data.
+ The package name will still default to 'main'.
+ 
+     $ cat testdata/gophercolor.png | ./bindata -f gophercolor_png | gofmt
+
  Invoke the program with the -h flag for more options.
 

bindata.go

@@ -28,40 +28,25 @@ func gofmt(file string) (err os.Error) {
 
 // Translate the input file.
 // input -> gzip -> gowriter -> output.
-func translate(input, output, pkgname, funcname string) (err os.Error) {
+func translate(input io.Reader, output io.Writer, pkgname, funcname string) (err os.Error) {
-	var fs, fd *os.File
 	var gz *gzip.Compressor
 
-	if fs, err = os.Open(input); err != nil {
+	fmt.Fprintf(output, `package %s
-		return
-	}
-
-	defer fs.Close()
-
-	if fd, err = os.Create(output); err != nil {
-		return
-	}
-
-	defer fd.Close()
-
-	fmt.Fprintf(fd, `// auto generated from '%s'.
-
-package %s
 import ( "io"; "os"; "bytes"; "compress/gzip" )
 
 func %s() ([]byte, os.Error) {
 var gz *gzip.Decompressor
 var err os.Error
-if gz, err = gzip.NewReader(bytes.NewBuffer([]byte{`, input, pkgname, funcname)
+if gz, err = gzip.NewReader(bytes.NewBuffer([]byte{`, pkgname, funcname)
 
-	if gz, err = gzip.NewWriter(&GoWriter{Writer: fd}); err != nil {
+	if gz, err = gzip.NewWriter(&GoWriter{Writer: output}); err != nil {
 		return
 	}
 
-	io.Copy(gz, fs)
+	io.Copy(gz, input)
 	gz.Close()
 
-	fmt.Fprint(fd, `
+	fmt.Fprint(output, `
 })); err != nil {
 	return nil, err
 }

main.go

@@ -15,11 +15,11 @@ import (
 
 const (
 	APP_NAME    = "bindata"
-	APP_VERSION = "0.2"
+	APP_VERSION = "0.3"
 )
 
 func main() {
-	in := flag.String("i", "", "Path to the input file.")
+	in := flag.String("i", "", "Path to the input file. Alternatively, pipe the file data into stdin.")
 	out := flag.String("o", "", "Optional path to the output file.")
 	pkgname := flag.String("p", "", "Optional name of the package to generate.")
 	funcname := flag.String("f", "", "Optional name of the function to generate.")
@@ -33,12 +33,9 @@ func main() {
 		return
 	}
 
-	if len(*in) == 0 {
+	pipe := len(*in) == 0
-		fmt.Fprintln(os.Stderr, "[e] No input file specified.")
-		os.Exit(1)
-	}
 
-	if len(*out) == 0 {
+	if !pipe && len(*out) == 0 {
 		// Ensure we create our own output filename that does not already exist.
 		dir, file := path.Split(*in)
 
@@ -67,6 +64,11 @@ func main() {
 	}
 
 	if len(*funcname) == 0 {
+		if pipe {
+			// Can't infer from input file name in this mode.
+			fmt.Fprintln(os.Stderr, "[e] No function name specified.")
+			os.Exit(1)
+		} else {
 			_, file := path.Split(*in)
 			file = strings.ToLower(file)
 			file = strings.Replace(file, " ", "_", -1)
@@ -75,19 +77,44 @@ func main() {
 			fmt.Fprintf(os.Stderr, "[w] No function name specified. Using '%s'.\n", file)
 			*funcname = file
 		}
+	}
 
 	// Read the input file, transform it into a gzip compressed data stream and
 	// write it out as a go source file.
-	if err := translate(*in, *out, *pkgname, *funcname); err != nil {
+	var err os.Error
+	if pipe {
+		if err = translate(os.Stdin, os.Stdout, *pkgname, *funcname); err != nil {
+			fmt.Fprintf(os.Stderr, "[e] %s\n", err)
+			return
+		}
+	} else {
+		var fs, fd *os.File
+
+		if fs, err = os.Open(*in); err != nil {
+			fmt.Fprintf(os.Stderr, "[e] %s\n", err)
+			return
+		}
+		
+		defer fs.Close()
+
+		if fd, err = os.Create(*out); err != nil {
+			fmt.Fprintf(os.Stderr, "[e] %s\n", err)
+			return
+		}
+		
+		defer fd.Close()
+
+		if err = translate(fs, fd, *pkgname, *funcname); err != nil {
 			fmt.Fprintf(os.Stderr, "[e] %s\n", err)
 			return
 		}
 
 		// If gofmt exists on the system, use it to format the generated source file.
-	if err := gofmt(*out); err != nil {
+		if err = gofmt(*out); err != nil {
 			fmt.Fprintf(os.Stderr, "[e] %s\n", err)
-		os.Exit(1)
+			return
 		}
 
 		fmt.Fprintln(os.Stdout, "[i] Done.")
 	}
+}

testdata/gophercolor.png.go

@@ -1,5 +1,3 @@
-// auto generated from 'testdata/gophercolor.png'.
-
 package main
 
 import (