dockerfile

Documentation

Overview

Package dockerfile provides Dockerfile parsing and rewriting capabilities.

Index

• func Rewrite(df *Dockerfile, opts RewriteOptions) string
• type Dockerfile
  • func Parse(path string) (*Dockerfile, error)
  • func ParseContent(content string) (*Dockerfile, error)
  • func (df *Dockerfile) GetBaseImage() string
  • func (df *Dockerfile) GetRunInstructions() []Instruction
  • func (df *Dockerfile) IsMultiStage() bool
• type Instruction
• type RewriteOptions

Functions

func Rewrite

func Rewrite(df *Dockerfile, opts RewriteOptions) string

Rewrite takes a parsed Dockerfile and produces an optimized version.

Types

type Dockerfile

type Dockerfile struct {
	// Instructions is the ordered list of instructions.
	Instructions []Instruction
	// Stages is the number of build stages.
	Stages int
	// StageNames maps stage index to its AS alias.
	StageNames map[int]string
	// Raw is the original file content.
	Raw string
}

Dockerfile represents a parsed Dockerfile.

func Parse

func Parse(path string) (*Dockerfile, error)

Parse reads a Dockerfile from the given path and returns a parsed representation.

func ParseContent

func ParseContent(content string) (*Dockerfile, error)

ParseContent parses Dockerfile content from a string.

func (*Dockerfile) GetBaseImage

func (df *Dockerfile) GetBaseImage() string

GetBaseImage returns the base image from the first FROM instruction.

func (*Dockerfile) GetRunInstructions

func (df *Dockerfile) GetRunInstructions() []Instruction

GetRunInstructions returns all RUN instructions.

func (*Dockerfile) IsMultiStage

func (df *Dockerfile) IsMultiStage() bool

IsMultiStage returns true if the Dockerfile has more than one FROM instruction.

type Instruction

type Instruction struct {
	// Command is the instruction keyword (FROM, RUN, COPY, etc.).
	Command string
	// Args is everything after the command keyword.
	Args string
	// Original is the original raw line(s) from the Dockerfile.
	Original string
	// LineNumber is the starting line number (1-indexed).
	LineNumber int
	// Stage is the build stage this instruction belongs to.
	Stage int
	// StageName is the AS alias of the current stage (if any).
	StageName string
}

Instruction represents a single Dockerfile instruction.

type RewriteOptions

type RewriteOptions struct {
	// BaseImage overrides the auto-detected base image.
	BaseImage string
	// MultiStage forces a multi-stage rewrite.
	MultiStage bool
	// Ecosystems detected in the project.
	Ecosystems *ecosystem.DetectResult
	// Platform is an optional --platform value (e.g., "linux/amd64").
	Platform string
}

RewriteOptions controls how the Dockerfile is rewritten.