runtime

Documentation

Overview

Package runtime contains code suitable for deployer implementers but not Service Weaver application developers.

Index

• Constants
• func CheckWeaveletArgs(w *protos.WeaveletArgs) error
• func DataDir() (string, error)
• func LogsDir() string
• func NewTempDir() (string, error)
• func OnExitSignal(fn func())
• func ParseConfig(file string, input string, sectionValidator func(string, string) error) (*protos.AppConfig, error)
• func ParseConfigSection(key, shortKey string, sections map[string]string, dst any) error
• type Bootstrap
  • func GetBootstrap(ctx context.Context) (Bootstrap, error)
  • func (b Bootstrap) Exists() bool

Constants

const Main = "github.com/ServiceWeaver/weaver/Main"

Main is the name of the main component.

const (
	// WeaveletArgsKey is the environment variable that holds the base64 encoded
	// protos.WeaveletArgs message for a weavelet started by an envelope. For internal
	// use by Service Weaver infrastructure.
	WeaveletArgsKey = "WEAVELET_ARGS"
)

Functions

func CheckWeaveletArgs

func CheckWeaveletArgs(w *protos.WeaveletArgs) error

CheckWeaveletArgs checks that WeaveletArgs is well-formed.

func DataDir

func DataDir() (string, error)

DataDir returns the default directory for Service Weaver deployer data. The returned directory is $XDG_DATA_HOME/serviceweaver, or ~/.local/share/serviceweaver if XDG_DATA_HOME is not set.

We recommend that deployers store their data in a directory within this default directory. For example, the "weaver multi" deployer stores its data in "DataDir()/multi".

func LogsDir

func LogsDir() string

LogsDir returns the default directory for Service Weaver logs, $DIR/tmp/serviceweaver/logs where $DIR is the default directory used for temporary files (see os.TempDir for details). We recommend that deployers store their logs in a directory within this default directory. For example, on Unix systems, the "weaver multi" deployer stores its data in /tmp/serviceweaver/logs/multi.

func NewTempDir

func NewTempDir() (string, error)

NewTempDir returns a new directory, e.g., to hold Unix domain sockets for internal communication. The new directory is not accessible by other users. Caller is responsible for cleaning up the directory when not needed.

func OnExitSignal

func OnExitSignal(fn func())

OnExitSignal arranges to run fn() when a signal that might cause the process to exit is delivered.

func ParseConfig

func ParseConfig(file string, input string, sectionValidator func(string, string) error) (*protos.AppConfig, error)

ParseConfig parses the specified configuration input, which should hold a set of sections in TOML format from the specified file. The section corresponding to the common Service Weaver application configuration is parsed and returned as a *AppConfig.

sectionValidator(key, val) is used to validate every section config entry.

func ParseConfigSection

func ParseConfigSection(key, shortKey string, sections map[string]string, dst any) error

ParseConfigSection parses the config section for key into dst. If shortKey is not empty, either key or shortKey is accepted. If the named section is not found, returns nil without changing dst.

Types

type Bootstrap

type Bootstrap struct {
	Args *protos.WeaveletArgs
}

Bootstrap holds configuration information used to start a process execution.

func GetBootstrap

func GetBootstrap(ctx context.Context) (Bootstrap, error)

GetBootstrap returns information needed to configure process execution. For normal execution, this comes from the environment. For weavertest, it comes from a context value.

func (Bootstrap) Exists

func (b Bootstrap) Exists() bool

Exists returns true if bootstrap information has been supplied. This is true except in the case of singleprocess.