tesson

Documentation

Overview

Package tesson contains Tesson core implementation details.

Tesson has several main abstractions: Topology, RuntimeContext and Frontend.

Topology's responsible for gathering the information about hardware layout of the machine, analysing it and generating a deployment plan.

RuntimeContext is an abstraction over execution engine, e.g. Docker Engine. It is supposed to spin up instances based on the deployment plan provided by Topology.

Frontend is an optional component which represents a load balancer. It will be used to set up a virtual service, and aggregate all shards under a single endpoint.

Default implementation is based on libhwloc, docker & gorb.

Index

• type DistributeOptions
• type ExecOptions
• type Frontend
  • func NewGorbFrontend(uri string) (Frontend, error)
• type Granularity
  • func ParseGranularity(g string) (Granularity, error)
• type Group
• type RuntimeContext
  • func NewDockerContext(ctx context.Context) (RuntimeContext, error)
• type Shard
• type StopOptions
• type Topology
  • func NewHwlocTopology() (Topology, error)
• type Unit

Types

type DistributeOptions

type DistributeOptions struct {
	Granularity Granularity
}

DistributeOptions specifies options for Distribute.

type ExecOptions

type ExecOptions struct {
	Image  string   // Container image name.
	Layout []Unit   // Hardware layout.
	Ports  []string // Exposed ports to publish.
	Config string   // Container config file.
}

ExecOptions specifies options for Exec.

type Frontend

type Frontend interface {
	CreateService(group string, shards []Shard) error
	RemoveService(group string, shards []Shard) error
}

Frontend represents a load balancer.

func NewGorbFrontend

func NewGorbFrontend(uri string) (Frontend, error)

NewGorbFrontend constructs a new Frontend powered by Gorb.

type Granularity

type Granularity uint

Granularity specifies distribution granularity.

const (
	NodeGranularity Granularity = iota
	CoreGranularity
)

A list of supported distribution granularities.

func ParseGranularity

func ParseGranularity(g string) (Granularity, error)

ParseGranularity parses granularity strings.

type Group

type Group struct {
	Name   string  // Human-readable group name.
	Image  string  // Container image name.
	Shards []Shard // Associated shards.
}

Group represents runtime group status.

type RuntimeContext

type RuntimeContext interface {
	Exec(group string, opts ExecOptions) (Group, error)
	List() ([]Group, error)
	Info(group string) (Group, error)
	Stop(group string, opts StopOptions) error
}

RuntimeContext represents an execution engine.

func NewDockerContext

func NewDockerContext(ctx context.Context) (RuntimeContext, error)

NewDockerContext constructs a new Docker-powered RuntimeContext.

type Shard

type Shard struct {
	Name   string // Human-readable shard name.
	ID     string // Unique shard ID.
	Status string // Status string.
	Unit   Unit   // Hardware layout.
	Ports  []types.Port
}

Shard represents runtime shard status.

type StopOptions

type StopOptions struct {
	Purge   bool          // Removes the container and its volumes.
	Timeout time.Duration // Timeout to SIGKILL.
}

StopOptions specifies options for Stop.

type Topology

type Topology interface {
	N() int
	Distribute(n int, opts DistributeOptions) ([]Unit, error)
}

Topology represents the hardware layout of a machine.

func NewHwlocTopology

func NewHwlocTopology() (Topology, error)

NewHwlocTopology constructs a Topology for the local machine, implemented in terms of libhwloc.

type Unit

type Unit interface {
	String() string
	Weight() int
}

Unit represents a unit of allocation (e.g. cpuset).