sherpa

Documentation

Index

• func AppendToEnvVar(name string, delimiter string, values ...string) string
• func CopyFile(source *os.File, destination string) error
• func Execute(f ExecuteFunc, options ...Option)
• func GetEnvRequired(name string) (string, error)
• func GetEnvWithDefault(name string, def string) string
• func Helpers(helpers map[string]ExecD, options ...Option) error
• func NewFileListingHash(roots ...string) (string, error)
• func NodeJSMainModule(path string) (string, error)
• func ResolveBool(name string) bool
• type Config
• type ExecD
• type ExecuteFunc
• type FileEntry
  • func NewFileListing(roots ...string) ([]FileEntry, error)
• type Option
  • func WithArguments(arguments []string) Option
  • func WithExecdWriter(writer io.Writer) Option
  • func WithExitHandler(exitHandler libcnb.ExitHandler) Option

Functions

func AppendToEnvVar

func AppendToEnvVar(name string, delimiter string, values ...string) string

AppendToEnvVar appends a collection of values to an env var separated by a delimiter. If the env var does not already exist, joins the values with the delimiter and returns the result.

func CopyFile

func CopyFile(source *os.File, destination string) error

CopyFile copies a file from the source to the destination. It ensures that the parent directory is created and matches the source and destination permissions.

func Execute

func Execute(f ExecuteFunc, options ...Option)

Execute is called by the main function of a buildpack helper application, for execution.

func GetEnvRequired

func GetEnvRequired(name string) (string, error)

GetEnvRequired returns the value of an environment variable if it exists, otherwise returns an error with a predictable message.

func GetEnvWithDefault

func GetEnvWithDefault(name string, def string) string

GetEnvWithWithDefault returns the value of an environment variable if it exists, otherwise returns the default.

func Helpers

func Helpers(helpers map[string]ExecD, options ...Option) error

Helpers is called by the main function of a buildpack's helper application, for execution.

func NewFileListingHash

func NewFileListingHash(roots ...string) (string, error)

NewFileListingHash generates a sha256 hash from the listing of all entries under the roots

func NodeJSMainModule

func NodeJSMainModule(path string) (string, error)

NodeJSMainModule returns the name of the main module as defined in <path>/package.json. If no package.json exists, or the package.json does not include a main entry, value defaults to server.js in line with the behavior of the Paketo NodeJS buildpack.

func ResolveBool

func ResolveBool(name string) bool

ResolveBool resolves a boolean value for a configuration option. Returns true for 1, t, T, TRUE, true, True. Returns false for all other values or unset.

Types

type Config

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

Config is an object that contains configurable properties for execution.

type ExecD

type ExecD interface {
	Execute() (map[string]string, error)
}

ExecD describes an interface for types that Exec.d specification.

type ExecuteFunc

type ExecuteFunc func() error

ExecuteFunc is the callback function for buildpack helper application implementations.

type FileEntry

type FileEntry struct {

	// Path is the path of a file.
	Path string `toml:"path"`

	// Mode is the mode of the source file.
	Mode string `toml:"mode"`

	// SHA256 is the SHA256 hash of the source file.
	SHA256 string `toml:"sha256,omitempty"`
}

FileEntry is metadata about a file.

func NewFileListing

func NewFileListing(roots ...string) ([]FileEntry, error)

NewFileListing generates a listing of all entries under the roots.

type Option

type Option func(config Config) Config

Option is a function for configuring a Config instance.

func WithArguments

func WithArguments(arguments []string) Option

WithArguments creates an Option that sets a collection of arguments.

func WithExecdWriter

func WithExecdWriter(writer io.Writer) Option

WithExecdWriter creates an Option that sets an exec.d Writer implementation.

func WithExitHandler

func WithExitHandler(exitHandler libcnb.ExitHandler) Option

WithExitHandler creates an Option that sets an ExitHandler implementation.