Fix transient mounts in Docker 1.12

README.md

@@ -40,10 +40,11 @@ To download and install the library and the binary, set up a Golang build enviro
 $ go get -u github.com/openshift/imagebuilder/cmd/imagebuilder
 ```
 
-The included command line takes two arguments, a path to a directory containing a dockerfile, and the name to tag the output image with.
+The included command line takes one argument, a path to a directory containing a Dockerfile. The `-t` option
+can be used to specify an image to tag as.
 
 ```
-$ imagebuilder path_to_directory output_image_name
+$ imagebuilder [-t TAG] DIRECTORY
 ```
 
 To mount a file into the image for build that will not be present in the final output image, run:
@@ -54,7 +55,18 @@ $ imagebuilder --mount ~/secrets/private.key:/etc/keys/private.key path/to/my/co
 
 Any processes in the Dockerfile will have access to `/etc/keys/private.key`, but that file will not be part of the committed image.
 
-Note that running `--mount` requires Docker 1.10 or newer, as it uses a Docker volume to hold the mounted files and the volume API was not available in earlier versions.
+Running `--mount` requires Docker 1.10 or newer, as it uses a Docker volume to hold the mounted files and the volume API was not
+available in earlier versions. In addition, there is currently a bug that blocks Docker 1.12 from using `--mount`.
+
+You can also customize which Dockerfile is run, or run multiple Dockerfiles in sequenc (the FROM is ignored on
+later files):
+
+```
+$ imagebuilder -f Dockerfile:Dockerfile.extra .
+```
+
+will build the current directory and combine the first Dockerfile with the second. The FROM in the second image
+is ignored.
 
 
 ## Code Example

builder.go

@@ -3,6 +3,7 @@ package imagebuilder
 import (
 	"bytes"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"log"
 	"os"
@@ -86,7 +87,7 @@ type Builder struct {
 	PendingRuns   []Run
 	PendingCopies []Copy
 
-	Executor Executor
+	//Executor Executor
 }
 
 func NewBuilder() *Builder {
@@ -100,6 +101,25 @@ func NewBuilder() *Builder {
 	}
 }
 
+func NewBuilderForReader(r io.Reader, args map[string]string) (*Builder, *parser.Node, error) {
+	b := NewBuilder()
+	b.Args = args
+	node, err := ParseDockerfile(r)
+	if err != nil {
+		return nil, nil, err
+	}
+	return b, node, err
+}
+
+func NewBuilderForFile(path string, args map[string]string) (*Builder, *parser.Node, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer f.Close()
+	return NewBuilderForReader(f, args)
+}
+
 // Step creates a new step from the current state.
 func (b *Builder) Step() *Step {
 	dst := make([]string, len(b.Env)+len(b.RunConfig.Env))

cmd/imagebuilder/imagebuilder.go

@@ -12,29 +12,34 @@ import (
 	docker "github.com/fsouza/go-dockerclient"
 	"github.com/golang/glog"
 
+	"github.com/openshift/imagebuilder"
 	"github.com/openshift/imagebuilder/dockerclient"
 )
 
 func main() {
 	log.SetFlags(0)
-	options := &dockerclient.ClientExecutor{}
+	options := dockerclient.NewClientExecutor(nil)
+	var tag string
 	var dockerfilePath string
 	var mountSpecs stringSliceFlag
 
-	flag.StringVar(&dockerfilePath, "dockerfile", dockerfilePath, "An optional path to a Dockerfile to use.")
+	flag.StringVar(&tag, "t", tag, "The name to assign this image, if any.")
+	flag.StringVar(&tag, "tag", tag, "The name to assign this image, if any.")
+	flag.StringVar(&dockerfilePath, "f", dockerfilePath, "An optional path to a Dockerfile to use. You may pass multiple docker files using the operating system delimiter.")
+	flag.StringVar(&dockerfilePath, "file", dockerfilePath, "An optional path to a Dockerfile to use. You may pass multiple docker files using the operating system delimiter.")
 	flag.Var(&mountSpecs, "mount", "An optional list of files and directories to mount during the build. Use SRC:DST syntax for each path.")
 	flag.BoolVar(&options.AllowPull, "allow-pull", true, "Pull the images that are not present.")
 	flag.BoolVar(&options.IgnoreUnrecognizedInstructions, "ignore-unrecognized-instructions", true, "If an unrecognized Docker instruction is encountered, warn but do not fail the build.")
 
 	flag.Parse()
 
 	args := flag.Args()
-	if len(args) != 2 {
-		log.Fatalf("You must provide two arguments: DIRECTORY and IMAGE_NAME")
+	if len(args) != 1 {
+		log.Fatalf("You must provide one argument, the name of a directory to build")
 	}
 
 	options.Directory = args[0]
-	options.Tag = args[1]
+	options.Tag = tag
 	if len(dockerfilePath) == 0 {
 		dockerfilePath = filepath.Join(options.Directory, "Dockerfile")
 	}
@@ -64,30 +69,56 @@ func main() {
 	// Accept ARGS on the command line
 	arguments := make(map[string]string)
 
-	if err := build(dockerfilePath, options, arguments); err != nil {
+	dockerfiles := filepath.SplitList(dockerfilePath)
+	if len(dockerfiles) == 0 {
+		dockerfiles = []string{filepath.Join(options.Directory, "Dockerfile")}
+	}
+
+	if err := build(dockerfiles[0], dockerfiles[1:], arguments, options); err != nil {
 		log.Fatal(err.Error())
 	}
 }
 
-func build(dockerfilePath string, e *dockerclient.ClientExecutor, arguments map[string]string) error {
+func build(dockerfile string, additionalDockerfiles []string, arguments map[string]string, e *dockerclient.ClientExecutor) error {
+	if err := e.DefaultExcludes(); err != nil {
+		return fmt.Errorf("error: Could not parse default .dockerignore: %v", err)
+	}
+
 	client, err := docker.NewClientFromEnv()
 	if err != nil {
-		log.Fatalf("No connection to Docker available: %v", err)
+		return fmt.Errorf("error: No connection to Docker available: %v", err)
 	}
 	e.Client = client
 
-	f, err := os.Open(dockerfilePath)
+	// TODO: handle signals
+	defer func() {
+		for _, err := range e.Release() {
+			fmt.Fprintf(e.ErrOut, "error: Unable to clean up build: %v\n", err)
+		}
+	}()
+
+	b, node, err := imagebuilder.NewBuilderForFile(dockerfile, arguments)
 	if err != nil {
 		return err
 	}
-	defer f.Close()
+	if err := e.Prepare(b, node); err != nil {
+		return err
+	}
+	if err := e.Execute(b, node); err != nil {
+		return err
+	}
 
-	// TODO: handle signals
-	if err := e.Cleanup(); err != nil {
-		fmt.Fprintf(e.ErrOut, "error: Unable to clean up build: %v\n", err)
+	for _, s := range additionalDockerfiles {
+		_, node, err := imagebuilder.NewBuilderForFile(s, arguments)
+		if err != nil {
+			return err
+		}
+		if err := e.Execute(b, node); err != nil {
+			return err
+		}
 	}
 
-	return e.Build(f, arguments)
+	return e.Commit(b)
 }
 
 type stringSliceFlag []string