anaconda buildpack for Python3 (#12)

* anaconda buildpack for Python3

* Support Anaconda 2, for Python 2, changes syntax

buildpacks/anaconda.go

@@ -0,0 +1,140 @@
+package buildpacks
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	. "github.com/yourbase/yb/plumbing"
+	. "github.com/yourbase/yb/types"
+)
+
+type AnacondaBuildTool struct {
+	BuildTool
+	version         string
+	spec            BuildToolSpec
+	pyCompatibleNum int
+}
+
+var ANACONDA_DIST_MIRROR = "https://repo.continuum.io/miniconda/Miniconda{{.PyNum}}-{{.Version}}-{{.OS}}-{{.Arch}}.{{.Extension}}"
+
+func NewAnaconda2BuildTool(toolSpec BuildToolSpec) AnacondaBuildTool {
+	tool := AnacondaBuildTool{
+		version:         toolSpec.Version,
+		spec:            toolSpec,
+		pyCompatibleNum: 2,
+	}
+
+	return tool
+}
+
+func NewAnaconda3BuildTool(toolSpec BuildToolSpec) AnacondaBuildTool {
+	tool := AnacondaBuildTool{
+		version:         toolSpec.Version,
+		spec:            toolSpec,
+		pyCompatibleNum: 3,
+	}
+
+	return tool
+}
+
+func (bt AnacondaBuildTool) Version() string {
+	return bt.version
+}
+
+func (bt AnacondaBuildTool) InstallDir() string {
+	return filepath.Join(bt.spec.PackageCacheDir, "miniconda", fmt.Sprintf("miniconda-%s", bt.Version()))
+}
+
+func (bt AnacondaBuildTool) Install() error {
+	anacondaDir := bt.InstallDir()
+	setupDir := bt.spec.PackageDir
+
+	if _, err := os.Stat(anacondaDir); err == nil {
+		fmt.Printf("anaconda installed in %s\n", anacondaDir)
+	} else {
+		fmt.Printf("Installing anaconda\n")
+
+		downloadUrl := bt.DownloadUrl()
+
+		fmt.Printf("Downloading Miniconda from URL %s...\n", downloadUrl)
+		localFile, err := DownloadFileWithCache(downloadUrl)
+		if err != nil {
+			fmt.Printf("Unable to download: %v\n", err)
+			return err
+		}
+		for _, cmd := range []string{
+			fmt.Sprintf("chmod +x %s", localFile),
+			fmt.Sprintf("bash %s -b -p %s", localFile, anacondaDir),
+		} {
+			fmt.Printf("Running: '%v' ", cmd)
+			ExecToStdout(cmd, setupDir)
+		}
+
+	}
+
+	return nil
+}
+
+func (bt AnacondaBuildTool) DownloadUrl() string {
+	opsys := OS()
+	arch := Arch()
+	extension := "sh"
+	version := bt.Version()
+
+	if version == "" {
+		version = "latest"
+	}
+
+	if arch == "amd64" {
+		arch = "x64"
+	}
+
+	if opsys == "darwin" {
+		opsys = "MacOSX"
+	}
+
+	if opsys == "linux" {
+		opsys = "Linux"
+	}
+
+	if opsys == "windows" {
+		opsys = "Windows"
+		extension = "exe"
+	}
+
+	data := struct {
+		PyNum     int
+		OS        string
+		Arch      string
+		Version   string
+		Extension string
+	}{
+		bt.pyCompatibleNum,
+		opsys,
+		arch,
+		version,
+		extension,
+	}
+
+	url, _ := TemplateToString(ANACONDA_DIST_MIRROR, data)
+
+	return url
+}
+
+func (bt AnacondaBuildTool) Setup() error {
+	installDir := bt.InstallDir()
+	PrependToPath(filepath.Join(installDir, "bin"))
+	setupDir := bt.spec.PackageDir
+
+	for _, cmd := range []string{
+		fmt.Sprintf("conda config --set always_yes yes --set changeps1 no"),
+		fmt.Sprintf("conda update -q conda"),
+	} {
+		fmt.Printf("Running: '%v' ", cmd)
+		ExecToStdout(cmd, setupDir)
+	}
+
+	return nil
+
+}

buildpacks/buildpack_loader.go

@@ -44,6 +44,10 @@ func LoadBuildPacks(dependencies []string, pkgCacheDir string, pkgDir string) ([
 		fmt.Printf("Configuring build tool: %s\n", toolSpec)
 
 		switch buildpackName {
+		case "anaconda2":
+			bt = NewAnaconda2BuildTool(spec)
+		case "anaconda3":
+			bt = NewAnaconda3BuildTool(spec)
 		case "ant":
 			bt = NewAntBuildTool(spec)
 		case "r":