moby/builder/builder.go
Tibor Vass 9be1ec60d4 builder: remove dependency on image
Signed-off-by: Tibor Vass <tibor@docker.com>
2015-12-16 19:25:03 +01:00

157 lines
5.6 KiB
Go

// Package builder defines interfaces for any Docker builder to implement.
//
// Historically, only server-side Dockerfile interpreters existed.
// This package allows for other implementations of Docker builders.
package builder
import (
"io"
"os"
"time"
"github.com/docker/docker/api/types"
"github.com/docker/docker/daemon"
"github.com/docker/docker/runconfig"
)
// Builder abstracts a Docker builder whose only purpose is to build a Docker image referenced by an imageID.
type Builder interface {
// Build builds a Docker image referenced by an imageID string.
//
// Note: Tagging an image should not be done by a Builder, it should instead be done
// by the caller.
//
// TODO: make this return a reference instead of string
Build() (imageID string)
}
// Context represents a file system tree.
type Context interface {
// Close allows to signal that the filesystem tree won't be used anymore.
// For Context implementations using a temporary directory, it is recommended to
// delete the temporary directory in Close().
Close() error
// Stat returns an entry corresponding to path if any.
// It is recommended to return an error if path was not found.
// If path is a symlink it also returns the path to the target file.
Stat(path string) (string, FileInfo, error)
// Open opens path from the context and returns a readable stream of it.
Open(path string) (io.ReadCloser, error)
// Walk walks the tree of the context with the function passed to it.
Walk(root string, walkFn WalkFunc) error
}
// WalkFunc is the type of the function called for each file or directory visited by Context.Walk().
type WalkFunc func(path string, fi FileInfo, err error) error
// ModifiableContext represents a modifiable Context.
// TODO: remove this interface once we can get rid of Remove()
type ModifiableContext interface {
Context
// Remove deletes the entry specified by `path`.
// It is usual for directory entries to delete all its subentries.
Remove(path string) error
}
// FileInfo extends os.FileInfo to allow retrieving an absolute path to the file.
// TODO: remove this interface once pkg/archive exposes a walk function that Context can use.
type FileInfo interface {
os.FileInfo
Path() string
}
// PathFileInfo is a convenience struct that implements the FileInfo interface.
type PathFileInfo struct {
os.FileInfo
// FilePath holds the absolute path to the file.
FilePath string
// Name holds the basename for the file.
FileName string
}
// Path returns the absolute path to the file.
func (fi PathFileInfo) Path() string {
return fi.FilePath
}
// Name returns the basename of the file.
func (fi PathFileInfo) Name() string {
if fi.FileName != "" {
return fi.FileName
}
return fi.FileInfo.Name()
}
// Hashed defines an extra method intended for implementations of os.FileInfo.
type Hashed interface {
// Hash returns the hash of a file.
Hash() string
SetHash(string)
}
// HashedFileInfo is a convenient struct that augments FileInfo with a field.
type HashedFileInfo struct {
FileInfo
// FileHash represents the hash of a file.
FileHash string
}
// Hash returns the hash of a file.
func (fi HashedFileInfo) Hash() string {
return fi.FileHash
}
// SetHash sets the hash of a file.
func (fi *HashedFileInfo) SetHash(h string) {
fi.FileHash = h
}
// Backend abstracts calls to a Docker Daemon.
type Backend interface {
// TODO: use digest reference instead of name
// GetImage looks up a Docker image referenced by `name`.
GetImage(name string) (Image, error)
// Pull tells Docker to pull image referenced by `name`.
Pull(name string) (Image, error)
// ContainerWsAttachWithLogs attaches to container.
ContainerWsAttachWithLogs(name string, cfg *daemon.ContainerWsAttachWithLogsConfig) error
// ContainerCreate creates a new Docker container and returns potential warnings
ContainerCreate(params *daemon.ContainerCreateConfig) (types.ContainerCreateResponse, error)
// ContainerRm removes a container specified by `id`.
ContainerRm(name string, config *types.ContainerRmConfig) error
// Commit creates a new Docker image from an existing Docker container.
Commit(string, *types.ContainerCommitConfig) (string, error)
// Kill stops the container execution abruptly.
ContainerKill(containerID string, sig uint64) error
// Start starts a new container
ContainerStart(containerID string, hostConfig *runconfig.HostConfig) error
// ContainerWait stops processing until the given container is stopped.
ContainerWait(containerID string, timeout time.Duration) (int, error)
// ContainerUpdateCmd updates container.Path and container.Args
ContainerUpdateCmd(containerID string, cmd []string) error
// ContainerCopy copies/extracts a source FileInfo to a destination path inside a container
// specified by a container object.
// TODO: make an Extract method instead of passing `decompress`
// TODO: do not pass a FileInfo, instead refactor the archive package to export a Walk function that can be used
// with Context.Walk
//ContainerCopy(name string, res string) (io.ReadCloser, error)
// TODO: use copyBackend api
BuilderCopy(containerID string, destPath string, src FileInfo, decompress bool) error
// TODO: remove
// Mount mounts the root filesystem for the container.
Mount(containerID string) error
// Unmount unmounts the root filesystem for the container.
Unmount(containerID string) error
}
// ImageCache abstracts an image cache store.
// (parent image, child runconfig) -> child image
type ImageCache interface {
// GetCachedImage returns a reference to a cached image whose parent equals `parent`
// and runconfig equals `cfg`. A cache miss is expected to return an empty ID and a nil error.
GetCachedImage(parentID string, cfg *runconfig.Config) (imageID string, err error)
}