From a36b3d3839b591677b76884fd282171d10bd53f4 Mon Sep 17 00:00:00 2001 From: Jim Teeuwen Date: Wed, 30 Oct 2013 16:08:29 +0100 Subject: [PATCH] Adds the -r command line flag. This determines if the input directory should be processed recursively or not. The default is false. Fixes the package to use this flag. Revises the README and adds a docs.go file which holds package documentation. --- README.md | 13 +++-- config.go | 6 +++ convert.go | 8 +-- doc.go | 129 +++++++++++++++++++++++++++++++++++++++++++++ go-bindata/main.go | 1 + 5 files changed, 149 insertions(+), 8 deletions(-) create mode 100644 doc.go diff --git a/README.md b/README.md index e33cdbd..5bf3c04 100644 --- a/README.md +++ b/README.md @@ -11,23 +11,26 @@ output being generated. ### Usage -Conversion is done on a tree of files. They are all embedded in a new +Conversion is done on a set of files. They are all embedded in a new Go source file, along with a table of contents and an `Asset` function, which allows quick access to the asset, based on its name. The simplest invocation generates a `bindata.go` file in the current -working directory. It includes all assets from the `data` directory and its -subdirectories. +working directory. It includes all assets from the `data` directory. $ go-bindata data/ +To include all input sub-directories recursively, add the `-r` flag, +otherwise it will only consider files in the input directory itself. + + $ go-bindata -r data/ + To specify the name of the output file being generated, we use the following: $ go-bindata data/ myfile.go The following paragraphs detail some of the command line options which can -supplied to `go-bindata`. These options allow us to customize the layout of -the generated code. +supplied to `go-bindata`. Refer to the `testdata/out` directory for various output examples from the assets in `testdata/in`. Each example uses different command line options. diff --git a/config.go b/config.go index 559930f..aeb3e0e 100644 --- a/config.go +++ b/config.go @@ -111,6 +111,11 @@ type Config struct { // Only in release mode, will the assets actually be embedded // in the code. The default behaviour is Release mode. Debug bool + + // Recursively process all assets in the input directory and its + // sub directories. This defaults to false, so only files in the + // input directory itself are read. + Recursive bool } // NewConfig returns a default configuration struct. @@ -120,6 +125,7 @@ func NewConfig() *Config { c.NoMemCopy = false c.NoCompress = false c.Debug = false + c.Recursive = false return c } diff --git a/convert.go b/convert.go index 2609a07..d38759f 100644 --- a/convert.go +++ b/convert.go @@ -26,7 +26,7 @@ func Translate(c *Config) error { } // Locate all the assets. - err = findFiles(c.Input, c.Prefix, &toc) + err = findFiles(c.Input, c.Prefix, c.Recursive, &toc) if err != nil { return err } @@ -71,7 +71,7 @@ func Translate(c *Config) error { // fillTOC recursively finds all the file paths in the given directory tree. // They are added to the given map as keys. Values will be safe function names // for each file, which will be used when generating the output code. -func findFiles(dir, prefix string, toc *[]Asset) error { +func findFiles(dir, prefix string, recursive bool, toc *[]Asset) error { if len(prefix) > 0 { dir, _ = filepath.Abs(dir) prefix, _ = filepath.Abs(prefix) @@ -95,7 +95,9 @@ func findFiles(dir, prefix string, toc *[]Asset) error { asset.Name = asset.Path if file.IsDir() { - findFiles(asset.Path, prefix, toc) + if recursive { + findFiles(asset.Path, prefix, recursive, toc) + } continue } diff --git a/doc.go b/doc.go new file mode 100644 index 0000000..09ead1e --- /dev/null +++ b/doc.go @@ -0,0 +1,129 @@ +// This work is subject to the CC0 1.0 Universal (CC0 1.0) Public Domain Dedication +// license. Its contents can be found at: +// http://creativecommons.org/publicdomain/zero/1.0/ + +/* +bindata converts any file into managable Go source code. Useful for +embedding binary data into a go program. The file data is optionally gzip +compressed before being converted to a raw byte slice. + +The following paragraphs cover some of the customization options +which can be specified in the Config struct, which must be passed into +the Translate() call. + + +Debug vs Release builds + +When used with the `Debug` option, the generated code does not actually include +the asset data. Instead, it generates function stubs which load the data from +the original file on disk. The asset API remains identical between debug and +release builds, so your code will not have to change. + +This is useful during development when you expect the assets to change often. +The host application using these assets uses the same API in both cases and +will not have to care where the actual data comes from. + +An example is a Go webserver with some embedded, static web content like +HTML, JS and CSS files. While developing it, you do not want to rebuild the +whole server and restart it every time you make a change to a bit of +javascript. You just want to build and launch the server once. Then just press +refresh in the browser to see those changes. Embedding the assets with the +`debug` flag allows you to do just that. When you are finished developing and +ready for deployment, just re-invoke `go-bindata` without the `-debug` flag. +It will now embed the latest version of the assets. + + +Lower memory footprint + +The `NoMemCopy` option will alter the way the output file is generated. +It will employ a hack that allows us to read the file data directly from +the compiled program's `.rodata` section. This ensures that when we call +call our generated function, we omit unnecessary memcopies. + +The downside of this, is that it requires dependencies on the `reflect` and +`unsafe` packages. These may be restricted on platforms like AppEngine and +thus prevent you from using this mode. + +Another disadvantage is that the byte slice we create, is strictly read-only. +For most use-cases this is not a problem, but if you ever try to alter the +returned byte slice, a runtime panic is thrown. Use this mode only on target +platforms where memory constraints are an issue. + +The default behaviour is to use the old code generation method. This +prevents the two previously mentioned issues, but will employ at least one +extra memcopy and thus increase memory requirements. + +For instance, consider the following two examples: + +This would be the default mode, using an extra memcopy but gives a safe +implementation without dependencies on `reflect` and `unsafe`: + + func myfile() []byte { + return []byte{0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a} + } + +Here is the same functionality, but uses the `.rodata` hack. +The byte slice returned from this example can not be written to without +generating a runtime error. + + var _myfile = "\x89\x50\x4e\x47\x0d\x0a\x1a" + + func myfile() []byte { + var empty [0]byte + sx := (*reflect.StringHeader)(unsafe.Pointer(&_myfile)) + b := empty[:] + bx := (*reflect.SliceHeader)(unsafe.Pointer(&b)) + bx.Data = sx.Data + bx.Len = len(_myfile) + bx.Cap = bx.Len + return b + } + + +Optional compression + +The NoCompress option indicates that the supplied assets are *not* GZIP +compressed before being turned into Go code. The data should still be accessed +through a function call, so nothing changes in the API. + +This feature is useful if you do not care for compression, or the supplied +resource is already compressed. Doing it again would not add any value and may +even increase the size of the data. + +The default behaviour of the program is to use compression. + + +Path prefix stripping + +The keys used in the `_bindata` map are the same as the input file name +passed to `go-bindata`. This includes the path. In most cases, this is not +desireable, as it puts potentially sensitive information in your code base. +For this purpose, the tool supplies another command line flag `-prefix`. +This accepts a portion of a path name, which should be stripped off from +the map keys and function names. + +For example, running without the `-prefix` flag, we get: + + $ go-bindata /path/to/templates/ + + _bindata["/path/to/templates/foo.html"] = path_to_templates_foo_html + +Running with the `-prefix` flag, we get: + + $ go-bindata -prefix "/path/to/" /path/to/templates/ + + _bindata["templates/foo.html"] = templates_foo_html + + +Build tags + +With the optional Tags field, you can specify any go build tags that +must be fulfilled for the output file to be included in a build. This +is useful when including binary data in multiple formats, where the desired +format is specified at build time with the appropriate tags. + +The tags are appended to a `// +build` line in the beginning of the output file +and must follow the build tags syntax specified by the go tool. + +*/ +package bindata diff --git a/go-bindata/main.go b/go-bindata/main.go index 3820003..a9bf79e 100644 --- a/go-bindata/main.go +++ b/go-bindata/main.go @@ -41,6 +41,7 @@ func parseArgs() *bindata.Config { flag.StringVar(&c.Tags, "tags", c.Tags, "Optional set of uild tags to include.") flag.StringVar(&c.Prefix, "prefix", c.Prefix, "Optional path prefix to strip off asset names.") flag.StringVar(&c.Package, "pkg", c.Package, "Package name to use in the generated code.") + flag.BoolVar(&c.Recursive, "r", c.Recursive, "Recursive processing of the target directory and all its sub-directories.") flag.BoolVar(&c.NoMemCopy, "nomemcopy", c.NoMemCopy, "Use a .rodata hack to get rid of unnecessary memcopies. Refer to the documentation to see what implications this carries.") flag.BoolVar(&c.NoCompress, "nocompress", c.NoCompress, "Assets will *not* be GZIP compressed when this flag is specified.") flag.BoolVar(&version, "version", false, "Displays version information.")