vessel/vessel.go

package vessel

import (
	"fmt"
	"io/ioutil"
	"os"
)

// Open tries to open the file at src as a vessel.Bundle
func Open(src string) (*Bundle, error) {
	r, err := os.Open(src)
	if err != nil {
		return nil, err
	}

	b := &Bundle{
		file: r,
	}

	err = b.tryLoadEmbeddedBundle()
	if err != nil {
		b.Close()
		return nil, err
	}
	return b, nil
}

// Create attaches a src file to a dest to create a vessel bundle
func Create(dst, src string, overWrite bool) (*Bundle, error) {
	b, err := Open(dst)
	if err == nil {
		truncateAt := b.offset
		b.Close()

		if !overWrite {
			return nil, fmt.Errorf("already a bundle")
		}

		err = os.Truncate(dst, truncateAt)
		if err != nil {
			return nil, err
		}
	}

	err = concatenate(dst, src)
	if err != nil {
		return nil, err
	}

	return Open(dst)
}

// Create attaches a src file to a dest to create a vessel bundle
func Build(dst, src string, overWrite bool, filter func(file string) bool) (*Bundle, error) {
	b, err := Open(dst)
	if err == nil {
		truncateAt := b.offset
		b.Close()

		if !overWrite {
			return nil, fmt.Errorf("already a bundle")
		}

		err = os.Truncate(dst, truncateAt)
		if err != nil {
			return nil, err
		}
	}

	file, err := ioutil.TempFile("./", "build.zip")
	if err != nil {
		return nil, err
	}
	defer os.Remove(file.Name())

	err = packInto(file, src, filter)
	if err != nil {
		return nil, err
	}

	err = concatenate(dst, file.Name())
	if err != nil {
		return nil, err
	}

	return Open(dst)
}

// Self returns a bundle that is embedded in the binary executable
func Self() (*Bundle, error) {
	ename, err := os.Executable()
	if err != nil {
		panic(err)
	}

	return Open(ename)
}