py-wheel.go

package main

import (
	"archive/zip"
	"fmt"
	"io/ioutil"
	"os"
	"strings"
)

// The metadata about the archive itself in the same basic key: value format.
type Wheel struct {
	// `Wheel-Version` is the version number of the Wheel specification.
	WheelVersion string
	// `Generator` is the name and optionally the version of the software
	// that produced the archive.
	Generator string
	// `Root-Is-Purelib` is true if the top level directory of the archive
	// should be installed into purelib; otherwise the root should be
	// installed into platlib.
	RootIsPurelib bool
	// `Tag` is the wheel's expanded compatibility tags; in the example the filename would contain py2.py3-none-any.
	Tag []string
	// Build is the build number and is omitted if there is no build number.
	Build string
}

func WheelUnpack(filename string) (reader *zip.ReadCloser, err error) {
	return zip.OpenReader(filename)
}

func ReadWheel(f *zip.File) (wheel Wheel, err error) {
	rc, err := f.Open()
	if err != nil {
		return Wheel{}, err
	}
	defer rc.Close()

	bytes, err := ioutil.ReadAll(rc)
	content := string(bytes)
	for _, line := range strings.Split(content, "\n") {
		if strings.TrimSpace(line) == "" {
			continue
		}

		sep := strings.Index(line, ":")
		if sep == -1 {
			return Wheel{}, fmt.Errorf("wheel: broken sep in WHEEL: %v", line)
		}

		key, value := line[0:sep], line[sep+1:len(line)]
		switch key {
		case "Wheel-Version":
			wheel.WheelVersion = value
		case "Generator":
			wheel.Generator = value
		case "Root-Is-Purelib":
			wheel.RootIsPurelib = value == "true"
		case "Tag":
			wheel.Tag = append(wheel.Tag, value)
		case "Build":
			wheel.Build = value
		}
	}
	return wheel, nil
}

func main() {
	filename := os.Args[1]
	fmt.Println("Parsing: " + filename)

	r, err := WheelUnpack(filename)
	if err != nil {
		panic(err)
	}
	defer r.Close()

	for _, f := range r.File {
		// fmt.Println(f.Name)
		chunks := strings.Split(f.Name, "/")
		if chunks[len(chunks)-1] == "WHEEL" {
			wheel, err := ReadWheel(f)
			if err != nil {
				panic(err)
			}
			fmt.Println(wheel)
		}
	}
}