env

Documentation

Overview

Package env contains common command line and initialization code for SCION services. If something is specific to one app, it should go into that app's code and not here.

During initialization, SIGHUPs are masked. To call a function on each SIGHUP, pass the function when calling Init.

Index

• Constants
• Variables
• func AddFlags()
• func CheckFlags(sampler config.Sampler) (int, bool)
• func ConfigFile() string
• func LogAppStarted(svcType, elemID string) error
• func LogAppStopped(svcType, elemID string)
• func ReloadTopology(topologyPath string)
• func SetupEnv(reloadF func())
• func Usage()
• func VersionInfo() string
• type Features
  • func (cfg *Features) ConfigName() string
  • func (cfg *Features) Sample(dst io.Writer, path config.Path, ctx config.CtxMap)
• type General
  • func (cfg *General) ConfigName() string
  • func (cfg *General) InitDefaults()
  • func (cfg *General) Sample(dst io.Writer, path config.Path, ctx config.CtxMap)
  • func (cfg *General) StaticInfoConfig() string
  • func (cfg *General) Topology() string
  • func (cfg *General) Validate() error
• type Metrics
  • func (cfg *Metrics) ConfigName() string
  • func (cfg *Metrics) Sample(dst io.Writer, path config.Path, _ config.CtxMap)
  • func (cfg *Metrics) StartPrometheus()
• type QUIC
  • func (cfg *QUIC) ConfigName() string
  • func (cfg *QUIC) Sample(dst io.Writer, path config.Path, _ config.CtxMap)
• type SCIONDClient
  • func (cfg *SCIONDClient) ConfigName() string
  • func (cfg *SCIONDClient) InitDefaults()
  • func (cfg *SCIONDClient) Sample(dst io.Writer, path config.Path, _ config.CtxMap)
  • func (cfg *SCIONDClient) Validate() error
• type Tracing
  • func (cfg *Tracing) ConfigName() string
  • func (cfg *Tracing) InitDefaults()
  • func (cfg *Tracing) NewTracer(id string) (opentracing.Tracer, io.Closer, error)
  • func (cfg *Tracing) Sample(dst io.Writer, path config.Path, _ config.CtxMap)

Constants

const (
	// TopologyFile is the file name for the topology file.
	TopologyFile = "topology.json"

	// StaticInfoConfigFile is the file name for the configuration file
	// used for the StaticInfo beacon extension.
	StaticInfoConfigFile = "staticInfoConfig.json"

	// SciondInitConnectPeriod is the default total amount of time spent
	// attempting to connect to sciond on start.
	SciondInitConnectPeriod = 20 * time.Second

	// ShutdownGraceInterval is the time applications wait after issuing a
	// clean shutdown signal, before forcerfully tearing down the application.
	ShutdownGraceInterval = 5 * time.Second
)

Variables

var (
	// The value is generated by tools/git-version.
	StartupVersion string
)

Startup* variables are set during link time.

Functions

func AddFlags

func AddFlags()

AddFlags adds the config and sample flags.

func CheckFlags

func CheckFlags(sampler config.Sampler) (int, bool)

CheckFlags checks whether the config or help-config flags have been set. In case the help-config flag is set, the config flag is ignored and a commented sample config is written to stdout.

The first return value is the return code of the program. The second value indicates whether the program can continue with its execution or should exit.

func ConfigFile

func ConfigFile() string

ConfigFile returns the config file path passed through the flag.

func LogAppStarted

func LogAppStarted(svcType, elemID string) error

LogAppStarted should be called by applications as soon as logging is initialized.

func LogAppStopped

func LogAppStopped(svcType, elemID string)

func ReloadTopology

func ReloadTopology(topologyPath string)

func SetupEnv

func SetupEnv(reloadF func())

SetupEnv initializes a basic environment for applications. If reloadF is not nil, the application will call reloadF whenever it receives a SIGHUP signal.

func Usage

func Usage()

Usage outputs run-time help to stdout.

func VersionInfo

func VersionInfo() string

VersionInfo returns build version information (build date, build version, build chain).

Types

type Features

type Features struct {
	config.NoDefaulter
	config.NoValidator
}

Features contains all feature flags. Add feature flags to this structure as needed. Feature flags are always boolean. Don't use any other types here!

func (*Features) ConfigName

func (cfg *Features) ConfigName() string

func (*Features) Sample

func (cfg *Features) Sample(dst io.Writer, path config.Path, ctx config.CtxMap)

type General

type General struct {
	// ID is the SCION element ID. This is used to choose the relevant
	// portion of the topology file for some services.
	ID string `toml:"id,omitempty"`
	// ConfigDir for loading extra files (currently, only topology.json and staticInfoConfig.json)
	ConfigDir string `toml:"config_dir,omitempty"`
	// ReconnectToDispatcher can be set to true to enable transparent dispatcher
	// reconnects.
	ReconnectToDispatcher bool `toml:"reconnect_to_dispatcher,omitempty"`
}

func (*General) ConfigName

func (cfg *General) ConfigName() string

func (*General) InitDefaults

func (cfg *General) InitDefaults()

InitDefaults sets the default value for Topology if not already set.

func (*General) Sample

func (cfg *General) Sample(dst io.Writer, path config.Path, ctx config.CtxMap)

func (*General) StaticInfoConfig

func (cfg *General) StaticInfoConfig() string

StaticInfoConfig return the path to the configuration file for the StaticInfo beacon extension.

func (*General) Topology

func (cfg *General) Topology() string

Topology returns the path to the topology file

func (*General) Validate

func (cfg *General) Validate() error

type Metrics

type Metrics struct {
	config.NoDefaulter
	config.NoValidator
	// Prometheus contains the address to export prometheus metrics on. If
	// not set, metrics are not exported.
	Prometheus string `toml:"prometheus,omitempty"`
}

func (*Metrics) ConfigName

func (cfg *Metrics) ConfigName() string

func (*Metrics) Sample

func (cfg *Metrics) Sample(dst io.Writer, path config.Path, _ config.CtxMap)

func (*Metrics) StartPrometheus

func (cfg *Metrics) StartPrometheus()

type QUIC

type QUIC struct {
	Address string `toml:"address,omitempty"`
}

QUIC contains configuration for control-plane speakers.

func (*QUIC) ConfigName

func (cfg *QUIC) ConfigName() string

func (*QUIC) Sample

func (cfg *QUIC) Sample(dst io.Writer, path config.Path, _ config.CtxMap)

type SCIONDClient

type SCIONDClient struct {
	// Address of the SCIOND server the client should connect to. Defaults to
	// 127.0.0.1:30255.
	Address string `toml:"address,omitempty"`
	// InitialConnectPeriod is the maximum amount of time spent attempting to
	// connect to sciond on start.
	InitialConnectPeriod util.DurWrap `toml:"initial_connect_period,omitempty"`
	// FakeData can be used to replace the local SCIOND with a fake data source.
	// It must point to a fake SCIOND configuration file.
	FakeData string `toml:"fake_data,omitempty"`
}

SCIONDClient contains information for running snet with sciond.

func (*SCIONDClient) ConfigName

func (cfg *SCIONDClient) ConfigName() string

func (*SCIONDClient) InitDefaults

func (cfg *SCIONDClient) InitDefaults()

func (*SCIONDClient) Sample

func (cfg *SCIONDClient) Sample(dst io.Writer, path config.Path, _ config.CtxMap)

func (*SCIONDClient) Validate

func (cfg *SCIONDClient) Validate() error

type Tracing

type Tracing struct {
	// Enabled enables tracing for this service.
	Enabled bool `toml:"enabled,omitempty"`
	// Enable debug mode.
	Debug bool `toml:"debug,omitempty"`
	// Agent is the address of the local agent that handles the reported
	// traces. (default: localhost:6831)
	Agent string `toml:"agent,omitempty"`
}

Tracing contains configuration for tracing.

func (*Tracing) ConfigName

func (cfg *Tracing) ConfigName() string

func (*Tracing) InitDefaults

func (cfg *Tracing) InitDefaults()

func (*Tracing) NewTracer

func (cfg *Tracing) NewTracer(id string) (opentracing.Tracer, io.Closer, error)

NewTracer creates a new Tracer for the given configuration. In case tracing is disabled this still returns noop-objects for convenience of the caller.

func (*Tracing) Sample

func (cfg *Tracing) Sample(dst io.Writer, path config.Path, _ config.CtxMap)