Add compression_level option to vagrant post-processors

post-processor/vagrant/aws.go

 package vagrant
 
 import (
+	"compress/flate"
 	"fmt"
 	"github.com/mitchellh/packer/common"
 	"github.com/mitchellh/packer/packer"
@@ -8,6 +9,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 )
 
@@ -16,6 +18,7 @@ type AWSBoxConfig struct {
 
 	OutputPath          string `mapstructure:"output"`
 	VagrantfileTemplate string `mapstructure:"vagrantfile_template"`
+	CompressionLevel    string `mapstructure:"compression_level"`
 
 	tpl *packer.ConfigTemplate
 }
@@ -46,6 +49,7 @@ func (p *AWSBoxPostProcessor) Configure(raws ...interface{}) error {
 	validates := map[string]*string{
 		"output":               &p.config.OutputPath,
 		"vagrantfile_template": &p.config.VagrantfileTemplate,
+		"compression_level":    &p.config.CompressionLevel,
 	}
 
 	for n, ptr := range validates {
@@ -127,6 +131,14 @@ func (p *AWSBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifact
 	vf.Write([]byte(vagrantfileContents))
 	vf.Close()
 
+	var level int = flate.DefaultCompression
+	if p.config.CompressionLevel != "" {
+		level, err = strconv.Atoi(p.config.CompressionLevel)
+		if err != nil {
+			return nil, false, err
+		}
+	}
+
 	// Create the metadata
 	metadata := map[string]string{"provider": "aws"}
 	if err := WriteMetadata(dir, metadata); err != nil {
@@ -134,7 +146,7 @@ func (p *AWSBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifact
 	}
 
 	// Compress the directory to the given output path
-	if err := DirToBox(outputPath, dir, ui); err != nil {
+	if err := DirToBox(outputPath, dir, ui, level); err != nil {
 		err = fmt.Errorf("error creating box: %s", err)
 		return nil, false, err
 	}

post-processor/vagrant/util.go

@@ -44,7 +44,7 @@ func CopyContents(dst, src string) error {
 // DirToBox takes the directory and compresses it into a Vagrant-compatible
 // box. This function does not perform checks to verify that dir is
 // actually a proper box. This is an expected precondition.
-func DirToBox(dst, dir string, ui packer.Ui) error {
+func DirToBox(dst, dir string, ui packer.Ui, level int) error {
 	log.Printf("Turning dir into box: %s => %s", dir, dst)
 	dstF, err := os.Create(dst)
 	if err != nil {
@@ -52,7 +52,10 @@ func DirToBox(dst, dir string, ui packer.Ui) error {
 	}
 	defer dstF.Close()
 
-	gzipWriter := gzip.NewWriter(dstF)
+	gzipWriter, err := gzip.NewWriterLevel(dstF, level)
+	if err != nil {
+		return err
+	}
 	defer gzipWriter.Close()
 
 	tarWriter := tar.NewWriter(gzipWriter)

post-processor/vagrant/virtualbox.go

@@ -2,6 +2,7 @@ package vagrant
 
 import (
 	"archive/tar"
+	"compress/flate"
 	"errors"
 	"fmt"
 	"github.com/mitchellh/packer/common"
@@ -12,6 +13,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"strconv"
 )
 
 type VBoxBoxConfig struct {
@@ -19,6 +21,7 @@ type VBoxBoxConfig struct {
 
 	OutputPath          string `mapstructure:"output"`
 	VagrantfileTemplate string `mapstructure:"vagrantfile_template"`
+	CompressionLevel    string `mapstructure:"compression_level"`
 
 	tpl *packer.ConfigTemplate
 }
@@ -49,6 +52,7 @@ func (p *VBoxBoxPostProcessor) Configure(raws ...interface{}) error {
 	validates := map[string]*string{
 		"output":               &p.config.OutputPath,
 		"vagrantfile_template": &p.config.VagrantfileTemplate,
+		"compression_level":    &p.config.CompressionLevel,
 	}
 
 	for n, ptr := range validates {
@@ -141,6 +145,14 @@ func (p *VBoxBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifac
 	vf.Write([]byte(vagrantfileContents))
 	vf.Close()
 
+	var level int = flate.DefaultCompression
+	if p.config.CompressionLevel != "" {
+		level, err = strconv.Atoi(p.config.CompressionLevel)
+		if err != nil {
+			return nil, false, err
+		}
+	}
+
 	// Create the metadata
 	metadata := map[string]string{"provider": "virtualbox"}
 	if err := WriteMetadata(dir, metadata); err != nil {
@@ -155,7 +167,7 @@ func (p *VBoxBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifac
 
 	// Compress the directory to the given output path
 	ui.Message(fmt.Sprintf("Compressing box..."))
-	if err := DirToBox(outputPath, dir, ui); err != nil {
+	if err := DirToBox(outputPath, dir, ui, level); err != nil {
 		return nil, false, err
 	}
 

post-processor/vagrant/vmware.go

 package vagrant
 
 import (
+	"compress/flate"
 	"fmt"
 	"github.com/mitchellh/packer/common"
 	"github.com/mitchellh/packer/packer"
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"strconv"
 )
 
 type VMwareBoxConfig struct {
@@ -14,6 +16,7 @@ type VMwareBoxConfig struct {
 
 	OutputPath          string `mapstructure:"output"`
 	VagrantfileTemplate string `mapstructure:"vagrantfile_template"`
+	CompressionLevel    string `mapstructure:"compression_level"`
 
 	tpl *packer.ConfigTemplate
 }
@@ -40,6 +43,7 @@ func (p *VMwareBoxPostProcessor) Configure(raws ...interface{}) error {
 	validates := map[string]*string{
 		"output":               &p.config.OutputPath,
 		"vagrantfile_template": &p.config.VagrantfileTemplate,
+		"compression_level":    &p.config.CompressionLevel,
 	}
 
 	for n, ptr := range validates {
@@ -111,6 +115,14 @@ func (p *VMwareBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artif
 		vf.Close()
 	}
 
+	var level int = flate.DefaultCompression
+	if p.config.CompressionLevel != "" {
+		level, err = strconv.Atoi(p.config.CompressionLevel)
+		if err != nil {
+			return nil, false, err
+		}
+	}
+
 	// Create the metadata
 	metadata := map[string]string{"provider": "vmware_desktop"}
 	if err := WriteMetadata(dir, metadata); err != nil {
@@ -119,7 +131,7 @@ func (p *VMwareBoxPostProcessor) PostProcess(ui packer.Ui, artifact packer.Artif
 
 	// Compress the directory to the given output path
 	ui.Message(fmt.Sprintf("Compressing box..."))
-	if err := DirToBox(outputPath, dir, ui); err != nil {
+	if err := DirToBox(outputPath, dir, ui, level); err != nil {
 		return nil, false, err
 	}
 

website/source/docs/post-processors/vagrant.html.markdown

@@ -68,6 +68,11 @@ The AWS provider itself can be configured with specific options:
   this is a template that simply sets the AMIs for the various regions
   of the AWS build.
 
+* `compression_level` (integer) - An integer repesenting the
+  compression level to use when creating the Vagrant box.  Valid
+  values range from 0 to 9, with 0 being no compression and 9 being
+  the best compression.
+
 The `vagrantfile_template` has the `Images` variable which is a map
 of region (string) to AMI ID (string). An example Vagrantfile template for
 AWS is shown below. The example simply sets the AMI for each region.