bbgo_origin/util/embed/main.go

158 lines
3.5 KiB
Go
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2021-02-15 12:28:03 +00:00
package main
import (
"bytes"
"flag"
"fmt"
"io/ioutil"
"log"
"os"
"path/filepath"
"strings"
"text/template"
)
var funcs = map[string]interface{}{
"formatBytes": formatBytes,
}
var (
tmpl = template.Must(template.New("").Funcs(funcs).Parse(`// +build web
// code is generated by embed. DO NOT EDIT.
package {{ .Package }}
import (
"bytes"
"errors"
"net/http"
"os"
"time"
)
var assets = map[string][]byte{}
var FS = &fs{}
type fs struct {}
func (fs *fs) Open(name string) (http.File, error) {
if name == "/" {
return fs, nil;
}
b, ok := assets[name]
if !ok {
return nil, os.ErrNotExist
}
return &file{name: name, size: len(b), Reader: bytes.NewReader(b)}, nil
}
func (fs *fs) Close() error { return nil }
func (fs *fs) Read(p []byte) (int, error) { return 0, nil }
func (fs *fs) Seek(offset int64, whence int) (int64, error) { return 0, nil }
func (fs *fs) Stat() (os.FileInfo, error) { return fs, nil }
func (fs *fs) Name() string { return "/" }
func (fs *fs) Size() int64 { return 0 }
func (fs *fs) Mode() os.FileMode { return 0755}
func (fs *fs) ModTime() time.Time{ return time.Time{} }
func (fs *fs) IsDir() bool { return true }
func (fs *fs) Sys() interface{} { return nil }
func (fs *fs) Readdir(count int) ([]os.FileInfo, error) {
files := []os.FileInfo{}
for name, data := range assets {
files = append(files, &file{name: name, size: len(data), Reader: bytes.NewReader(data)})
}
return files, nil
}
type file struct {
name string
size int
*bytes.Reader
}
func (f *file) Close() error { return nil }
func (f *file) Readdir(count int) ([]os.FileInfo, error) { return nil, errors.New("readdir is not supported") }
func (f *file) Stat() (os.FileInfo, error) { return f, nil }
func (f *file) Name() string { return f.name }
func (f *file) Size() int64 { return int64(f.size) }
func (f *file) Mode() os.FileMode { return 0644 }
func (f *file) ModTime() time.Time{ return time.Time{} }
func (f *file) IsDir() bool { return false }
func (f *file) Sys() interface{} { return nil }
`)))
// Embed is a helper function that embeds assets from the given directories
// into a Go source file. It is designed to be called from some generator
// script, see example project to find out how it can be used.
func Embed(packageName, file string, dirs ...string) error {
var buf bytes.Buffer
// Execute template
if err := tmpl.Execute(&buf, struct{
Package string
}{
Package: packageName,
}); err != nil {
return err
}
w, err := os.Create(file)
if err != nil {
return err
}
defer w.Close()
fmt.Fprintln(w, buf.String())
fmt.Fprintln(w, `func init() {`)
for _, dir := range dirs {
filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
if info.IsDir() {
return nil
}
log.Printf("packing %s...", path)
b, err := ioutil.ReadFile(path)
if err != nil {
return err
}
path = filepath.ToSlash(path)
fmt.Fprintf(w, ` assets[%q] = []byte{`, strings.TrimPrefix(path, dir))
fmt.Fprintf(w, formatBytes(b))
fmt.Fprintln(w, `}`)
return nil
})
}
fmt.Fprintln(w, `}`)
return nil
}
func formatBytes(s []byte) string {
var builder strings.Builder
for _, v := range s {
builder.WriteString(fmt.Sprintf("0x%02x, ", int(v)))
}
return builder.String()
}
func main() {
var packageName string
var outputFile string
flag.StringVar(&packageName,"package", "", "package name")
flag.StringVar(&outputFile,"output", "assets.go", "output filename")
flag.Parse()
args := flag.Args()
if err := Embed(packageName, outputFile, args...) ; err != nil {
log.Fatal(err)
}
}