package docker import ( "bufio" "encoding/json" "fmt" "github.com/dotcloud/docker/utils" "io" "os" "path" "strings" "time" ) type Builder struct { runtime *Runtime repositories *TagStore graph *Graph } func NewBuilder(runtime *Runtime) *Builder { return &Builder{ runtime: runtime, graph: runtime.graph, repositories: runtime.repositories, } } func (builder *Builder) mergeConfig(userConf, imageConf *Config) { if userConf.Hostname != "" { userConf.Hostname = imageConf.Hostname } if userConf.User != "" { userConf.User = imageConf.User } if userConf.Memory == 0 { userConf.Memory = imageConf.Memory } if userConf.MemorySwap == 0 { userConf.MemorySwap = imageConf.MemorySwap } if userConf.CpuShares == 0 { userConf.CpuShares = imageConf.CpuShares } if userConf.PortSpecs == nil || len(userConf.PortSpecs) == 0 { userConf.PortSpecs = imageConf.PortSpecs } if !userConf.Tty { userConf.Tty = userConf.Tty } if !userConf.OpenStdin { userConf.OpenStdin = imageConf.OpenStdin } if !userConf.StdinOnce { userConf.StdinOnce = imageConf.StdinOnce } if userConf.Env == nil || len(userConf.Env) == 0 { userConf.Env = imageConf.Env } if userConf.Cmd == nil || len(userConf.Cmd) == 0 { userConf.Cmd = imageConf.Cmd } if userConf.Dns == nil || len(userConf.Dns) == 0 { userConf.Dns = imageConf.Dns } } func (builder *Builder) Create(config *Config) (*Container, error) { // Lookup image img, err := builder.repositories.LookupImage(config.Image) if err != nil { return nil, err } if img.Config != nil { builder.mergeConfig(config, img.Config) } if config.Cmd == nil || len(config.Cmd) == 0 { return nil, fmt.Errorf("No command specified") } // Generate id id := GenerateId() // Generate default hostname // FIXME: the lxc template no longer needs to set a default hostname if config.Hostname == "" { config.Hostname = id[:12] } container := &Container{ // FIXME: we should generate the ID here instead of receiving it as an argument Id: id, Created: time.Now(), Path: config.Cmd[0], Args: config.Cmd[1:], //FIXME: de-duplicate from config Config: config, Image: img.Id, // Always use the resolved image id NetworkSettings: &NetworkSettings{}, // FIXME: do we need to store this in the container? SysInitPath: sysInitPath, } container.root = builder.runtime.containerRoot(container.Id) // Step 1: create the container directory. // This doubles as a barrier to avoid race conditions. if err := os.Mkdir(container.root, 0700); err != nil { return nil, err } // If custom dns exists, then create a resolv.conf for the container if len(config.Dns) > 0 { container.ResolvConfPath = path.Join(container.root, "resolv.conf") f, err := os.Create(container.ResolvConfPath) if err != nil { return nil, err } defer f.Close() for _, dns := range config.Dns { if _, err := f.Write([]byte("nameserver " + dns + "\n")); err != nil { return nil, err } } } else { container.ResolvConfPath = "/etc/resolv.conf" } // Step 2: save the container json if err := container.ToDisk(); err != nil { return nil, err } // Step 3: register the container if err := builder.runtime.Register(container); err != nil { return nil, err } return container, nil } // Commit creates a new filesystem image from the current state of a container. // The image can optionally be tagged into a repository func (builder *Builder) Commit(container *Container, repository, tag, comment, author string, config *Config) (*Image, error) { // FIXME: freeze the container before copying it to avoid data corruption? // FIXME: this shouldn't be in commands. rwTar, err := container.ExportRw() if err != nil { return nil, err } // Create a new image from the container's base layers + a new layer from container changes img, err := builder.graph.Create(rwTar, container, comment, author, config) if err != nil { return nil, err } // Register the image if needed if repository != "" { if err := builder.repositories.Set(repository, tag, img.Id, true); err != nil { return img, err } } return img, nil } func (builder *Builder) clearTmp(containers, images map[string]struct{}) { for c := range containers { tmp := builder.runtime.Get(c) builder.runtime.Destroy(tmp) utils.Debugf("Removing container %s", c) } for i := range images { builder.runtime.graph.Delete(i) utils.Debugf("Removing image %s", i) } } func (builder *Builder) getCachedImage(image *Image, config *Config) (*Image, error) { // Retrieve all images images, err := builder.graph.All() if err != nil { return nil, err } // Store the tree in a map of map (map[parentId][childId]) imageMap := make(map[string]map[string]struct{}) for _, img := range images { if _, exists := imageMap[img.Parent]; !exists { imageMap[img.Parent] = make(map[string]struct{}) } imageMap[img.Parent][img.Id] = struct{}{} } // Loop on the children of the given image and check the config for elem := range imageMap[image.Id] { img, err := builder.graph.Get(elem) if err != nil { return nil, err } if CompareConfig(&img.ContainerConfig, config) { return img, nil } } return nil, nil } func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, error) { var ( image, base *Image config *Config maintainer string env map[string]string = make(map[string]string) tmpContainers map[string]struct{} = make(map[string]struct{}) tmpImages map[string]struct{} = make(map[string]struct{}) ) defer builder.clearTmp(tmpContainers, tmpImages) file := bufio.NewReader(dockerfile) for { line, err := file.ReadString('\n') if err != nil { if err == io.EOF { break } return nil, err } line = strings.Replace(strings.TrimSpace(line), " ", " ", 1) // Skip comments and empty line if len(line) == 0 || line[0] == '#' { continue } tmp := strings.SplitN(line, " ", 2) if len(tmp) != 2 { return nil, fmt.Errorf("Invalid Dockerfile format") } instruction := strings.Trim(tmp[0], " ") arguments := strings.Trim(tmp[1], " ") switch strings.ToLower(instruction) { case "from": fmt.Fprintf(stdout, "FROM %s\n", arguments) image, err = builder.runtime.repositories.LookupImage(arguments) if err != nil { // if builder.runtime.graph.IsNotExist(err) { // var tag, remote string // if strings.Contains(arguments, ":") { // remoteParts := strings.Split(arguments, ":") // tag = remoteParts[1] // remote = remoteParts[0] // } else { // remote = arguments // } // panic("TODO: reimplement this") // // if err := builder.runtime.graph.PullRepository(stdout, remote, tag, builder.runtime.repositories, builder.runtime.authConfig); err != nil { // // return nil, err // // } // image, err = builder.runtime.repositories.LookupImage(arguments) // if err != nil { // return nil, err // } // } else { return nil, err // } } config = &Config{} break case "maintainer": fmt.Fprintf(stdout, "MAINTAINER %s\n", arguments) maintainer = arguments break case "run": fmt.Fprintf(stdout, "RUN %s\n", arguments) if image == nil { return nil, fmt.Errorf("Please provide a source image with `from` prior to run") } config, _, err := ParseRun([]string{image.Id, "/bin/sh", "-c", arguments}, builder.runtime.capabilities) if err != nil { return nil, err } for key, value := range env { config.Env = append(config.Env, fmt.Sprintf("%s=%s", key, value)) } if cache, err := builder.getCachedImage(image, config); err != nil { return nil, err } else if cache != nil { image = cache fmt.Fprintf(stdout, "===> %s\n", image.ShortId()) break } utils.Debugf("Env -----> %v ------ %v\n", config.Env, env) // Create the container and start it c, err := builder.Create(config) if err != nil { return nil, err } if os.Getenv("DEBUG") != "" { out, _ := c.StdoutPipe() err2, _ := c.StderrPipe() go io.Copy(os.Stdout, out) go io.Copy(os.Stdout, err2) } if err := c.Start(); err != nil { return nil, err } tmpContainers[c.Id] = struct{}{} // Wait for it to finish if result := c.Wait(); result != 0 { return nil, fmt.Errorf("!!! '%s' return non-zero exit code '%d'. Aborting.", arguments, result) } // Commit the container base, err = builder.Commit(c, "", "", "", maintainer, nil) if err != nil { return nil, err } tmpImages[base.Id] = struct{}{} fmt.Fprintf(stdout, "===> %s\n", base.ShortId()) // use the base as the new image image = base break case "env": tmp := strings.SplitN(arguments, " ", 2) if len(tmp) != 2 { return nil, fmt.Errorf("Invalid ENV format") } key := strings.Trim(tmp[0], " ") value := strings.Trim(tmp[1], " ") fmt.Fprintf(stdout, "ENV %s %s\n", key, value) env[key] = value if image != nil { fmt.Fprintf(stdout, "===> %s\n", image.ShortId()) } else { fmt.Fprintf(stdout, "===> \n") } break case "cmd": fmt.Fprintf(stdout, "CMD %s\n", arguments) // Create the container and start it c, err := builder.Create(&Config{Image: image.Id, Cmd: []string{"", ""}}) if err != nil { return nil, err } if err := c.Start(); err != nil { return nil, err } tmpContainers[c.Id] = struct{}{} cmd := []string{} if err := json.Unmarshal([]byte(arguments), &cmd); err != nil { return nil, err } config.Cmd = cmd // Commit the container base, err = builder.Commit(c, "", "", "", maintainer, config) if err != nil { return nil, err } tmpImages[base.Id] = struct{}{} fmt.Fprintf(stdout, "===> %s\n", base.ShortId()) image = base break case "expose": ports := strings.Split(arguments, " ") fmt.Fprintf(stdout, "EXPOSE %v\n", ports) if image == nil { return nil, fmt.Errorf("Please provide a source image with `from` prior to copy") } // Create the container and start it c, err := builder.Create(&Config{Image: image.Id, Cmd: []string{"", ""}}) if err != nil { return nil, err } if err := c.Start(); err != nil { return nil, err } tmpContainers[c.Id] = struct{}{} config.PortSpecs = append(ports, config.PortSpecs...) // Commit the container base, err = builder.Commit(c, "", "", "", maintainer, config) if err != nil { return nil, err } tmpImages[base.Id] = struct{}{} fmt.Fprintf(stdout, "===> %s\n", base.ShortId()) image = base break case "insert": if image == nil { return nil, fmt.Errorf("Please provide a source image with `from` prior to copy") } tmp = strings.SplitN(arguments, " ", 2) if len(tmp) != 2 { return nil, fmt.Errorf("Invalid INSERT format") } sourceUrl := strings.Trim(tmp[0], " ") destPath := strings.Trim(tmp[1], " ") fmt.Fprintf(stdout, "COPY %s to %s in %s\n", sourceUrl, destPath, base.ShortId()) file, err := utils.Download(sourceUrl, stdout) if err != nil { return nil, err } defer file.Body.Close() config, _, err := ParseRun([]string{base.Id, "echo", "insert", sourceUrl, destPath}, builder.runtime.capabilities) if err != nil { return nil, err } c, err := builder.Create(config) if err != nil { return nil, err } if err := c.Start(); err != nil { return nil, err } // Wait for echo to finish if result := c.Wait(); result != 0 { return nil, fmt.Errorf("!!! '%s' return non-zero exit code '%d'. Aborting.", arguments, result) } if err := c.Inject(file.Body, destPath); err != nil { return nil, err } base, err = builder.Commit(c, "", "", "", maintainer, nil) if err != nil { return nil, err } fmt.Fprintf(stdout, "===> %s\n", base.ShortId()) image = base break default: fmt.Fprintf(stdout, "Skipping unknown instruction %s\n", strings.ToUpper(instruction)) } } if image != nil { // The build is successful, keep the temporary containers and images for i := range tmpImages { delete(tmpImages, i) } for i := range tmpContainers { delete(tmpContainers, i) } fmt.Fprintf(stdout, "Build finished. image id: %s\n", image.ShortId()) return image, nil } return nil, fmt.Errorf("An error occured during the build\n") }