andreychernih/railsbox

package main

import (
    "archive/tar"
    "compress/gzip"
    "io"
    "io/ioutil"
    "os"

    "github.com/jinzhu/gorm"
    "gopkg.in/yaml.v2"
)

type Metadata struct {
    Extensions []string
}

func process(db gorm.DB, gems <-chan Gem, done chan<- bool) {
    for gem := range gems {
        path := gem.GetFilePath()
        f, err := os.Open(path)
        handleError(err)

        tarReader := tar.NewReader(f)
        for {
            hdr, err := tarReader.Next()
            if err == io.EOF {
                break
            }
            handleError(err)

            if hdr.Name == "metadata.gz" {
                gzipReader, err := gzip.NewReader(tarReader)
                handleError(err)

                data, err := ioutil.ReadAll(gzipReader)
                handleError(err)

                metadata := Metadata{}
                err1 := yaml.Unmarshal(data, &metadata)
                handleError(err1)

                gem.HasNativeExtensions = len(metadata.Extensions) > 0
                db.Save(&gem)

                gzipReader.Close()
            }
        }

        f.Close()
    }

    done <- true
}

func DetectNativeDependencies(gr *GemRepository) {
    doneChan := make(chan bool)
    gems := gr.ProcessingQueue()
    go process(gr.db, gems, doneChan)
    <-doneChan
}