| package docker |
| |
| import ( |
| "bufio" |
| "fmt" |
| "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) Create(config *Config) (*Container, error) { |
| // Lookup image |
| img, err := builder.repositories.LookupImage(config.Image) |
| if err != nil { |
| return nil, err |
| } |
| // 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) (*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) |
| 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) |
| Debugf("Removing container %s", c) |
| } |
| for i := range images { |
| builder.runtime.graph.Delete(i) |
| Debugf("Removing image %s", i) |
| } |
| } |
| |
| func (builder *Builder) Build(dockerfile io.Reader, stdout io.Writer) (*Image, error) { |
| var ( |
| image, base *Image |
| 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.TrimSpace(line) |
| // 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") |
| } |
| switch tmp[0] { |
| case "from": |
| fmt.Fprintf(stdout, "FROM %s\n", tmp[1]) |
| image, err = builder.runtime.repositories.LookupImage(tmp[1]) |
| if err != nil { |
| return nil, err |
| } |
| break |
| case "run": |
| fmt.Fprintf(stdout, "RUN %s\n", tmp[1]) |
| 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", tmp[1]}, nil, builder.runtime.capabilities) |
| if err != nil { |
| return nil, err |
| } |
| |
| // Create the container and start it |
| c, err := builder.Create(config) |
| if err != nil { |
| return nil, err |
| } |
| 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.", tmp[1], result) |
| } |
| |
| // Commit the container |
| base, err = builder.Commit(c, "", "", "", "") |
| 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 "insert": |
| if image == nil { |
| return nil, fmt.Errorf("Please provide a source image with `from` prior to copy") |
| } |
| tmp2 := strings.SplitN(tmp[1], " ", 2) |
| if len(tmp) != 2 { |
| return nil, fmt.Errorf("Invalid INSERT format") |
| } |
| fmt.Fprintf(stdout, "COPY %s to %s in %s\n", tmp2[0], tmp2[1], base.ShortId()) |
| |
| file, err := Download(tmp2[0], stdout) |
| if err != nil { |
| return nil, err |
| } |
| defer file.Body.Close() |
| |
| config, err := ParseRun([]string{base.Id, "echo", "insert", tmp2[0], tmp2[1]}, nil, 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.", tmp[1], result) |
| } |
| |
| if err := c.Inject(file.Body, tmp2[1]); err != nil { |
| return nil, err |
| } |
| |
| base, err = builder.Commit(c, "", "", "", "") |
| 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", instruction) |
| } |
| } |
| if base != 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", base.ShortId()) |
| } else { |
| fmt.Fprintf(stdout, "An error occured during the build\n") |
| } |
| return base, nil |
| } |