mrd

type Controller struct {
	// The prefix added to Docker container and image names.
	// Used to prevent clashes with other images.
	NamePrefix string

	// The value for the mapreduced.ctl label added to containers and images.
	// Used to clean up objects left over from previous runs of the controller.
	LabelValue string

	// The number assigned to the next created Job.
	NextJobId int
	// contains filtered or unexported fields
}

type DefinitionReader struct {
	// contains filtered or unexported fields
}

type DockerDescriptor struct {
	// Executable + paramters used to run the Docker image.
	EntryPoint []string `yaml:"cmd"`

	// Current directory when the Docker image starts.
	WorkDir string `yaml:"chdir"`

	// Path where the job's input will be copied to.
	InputPath string `yaml:"input"`

	// Path where the job's output will be copied from.
	OutputPath string `yaml:"output"`
}

type Fetcher interface {
	// Activates this fetcher.
	// The fetcher must not do any work until Open() is called.
	// This must not be called multiple times.
	Open() error

	// Returns the information needed to create a zip.Reader.
	// This must not be called multiple times.
	Reader() (io.ReaderAt, int)

	// Deactivates this fetcher. The reader it returns is no longer usable.
	Close() error
}

type FileFetcher struct {
	// contains filtered or unexported fields
}

type Job struct {
	// The job's unique ID.
	ID string

	// Names for the Docker images created by this job.
	MapperImageName  string
	ReducerImageName string

	// The job description submitted to the Web service.
	Template *Template
	// contains filtered or unexported fields
}

type MapperDescriptor struct {
	DockerDescriptor `yaml:",inline"`

	// The name of the environment variable holding the current item's index.
	ItemEnvVar string `yaml:"env"`
}

type ReducerDescriptor struct {
	DockerDescriptor `yaml:",inline"`

	// The name of the environment variable holding the number of items.
	ItemCountVar string `yaml:"env"`
}

type StatefulFetcher interface {
	Fetcher

	// Returns true if Open() has been called on this fetcher.
	Opened() bool
	// Returns true if Close() has been called on this fetcher.
	Closed() bool
}

type Template struct {
	// The descriptor fields are only initialzed if State >= TemplateRead.
	TemplateDescriptor

	// Identifier assigned when the template is created
	ID string
	// The current state of the template
	State TemplateState
	// The first error that occurred while processing the template
	Err error
	// The output produced by Docker while building the base Docker image
	BuildOutput []byte
	// The ID of the template's base Docker image
	BaseImageID string
}

type TemplateDescriptor struct {
	// Number of times the mapper will run.
	ItemCount int `yaml:"items"`

	// Information about the map phase of the job.
	Mapper MapperDescriptor `yaml:"mapper"`

	// Information about the reduce phase of the job.
	Reducer ReducerDescriptor `yaml:"reducer"`
}

type TemplateState int