Documentation ¶
Index ¶
- Variables
- func CheckEmpty(args []string) error
- func FormatSmart(value interface{}) ([]byte, error)
- func FormatYaml(value interface{}) ([]byte, error)
- func IsRcPassthroughError(err error) bool
- func Main(c Command, ctx *Context, args []string) int
- func NewCommandLogWriter(name string, out, err io.Writer) loggo.Writer
- func NewRcPassthroughError(code int) error
- func ZeroOrOneArgs(args []string) (string, error)
- type AppendStringsValue
- type Command
- type CommandBase
- type Context
- func (ctx *Context) AbsPath(path string) string
- func (ctx *Context) GetStderr() io.Writer
- func (ctx *Context) GetStdin() io.Reader
- func (ctx *Context) GetStdout() io.Writer
- func (ctx *Context) Getenv(key string) string
- func (ctx *Context) Infof(format string, params ...interface{})
- func (ctx *Context) InterruptNotify(c chan<- os.Signal)
- func (ctx *Context) Setenv(key, value string) error
- func (ctx *Context) StopInterruptNotify(c chan<- os.Signal)
- func (ctx *Context) Verbosef(format string, params ...interface{})
- type DeprecationCheck
- type FileVar
- type Formatter
- type Info
- type Log
- type MissingCallback
- type Output
- type RcPassthroughError
- type StringsValue
- type SuperCommand
- func (c *SuperCommand) AddHelpTopic(name, short, long string, aliases ...string)
- func (c *SuperCommand) AddHelpTopicCallback(name, short string, longCallback func() string)
- func (c *SuperCommand) AllowInterspersedFlags() bool
- func (c *SuperCommand) Info() *Info
- func (c *SuperCommand) Init(args []string) error
- func (c *SuperCommand) IsSuperCommand() bool
- func (c *SuperCommand) Register(subcmd Command)
- func (c *SuperCommand) RegisterAlias(name, forName string, check DeprecationCheck)
- func (c *SuperCommand) RegisterDeprecated(subcmd Command, check DeprecationCheck)
- func (c *SuperCommand) RegisterSuperAlias(name, super, forName string, check DeprecationCheck)
- func (c *SuperCommand) Run(ctx *Context) error
- func (c *SuperCommand) SetCommonFlags(f *gnuflag.FlagSet)
- func (c *SuperCommand) SetFlags(f *gnuflag.FlagSet)
- type SuperCommandParams
- type UnrecognizedCommand
- type WriterFactory
Constants ¶
This section is empty.
Variables ¶
var DefaultFormatters = map[string]Formatter{ "smart": FormatSmart, "yaml": FormatYaml, "json": FormatJson, }
DefaultFormatters holds the formatters that can be specified with the --format flag.
var ErrNoPath = errors.New("path not set")
var ErrSilent = errors.New("cmd: error out silently")
ErrSilent can be returned from Run to signal that Main should exit with code 1 without producing error output.
var FormatJson = json.Marshal
FormatJson marshals value to a json-formatted []byte.
Functions ¶
func CheckEmpty ¶
CheckEmpty is a utility function that returns an error if args is not empty.
func FormatSmart ¶
FormatSmart marshals value into a []byte according to the following rules:
- string: untouched
- bool: converted to `True` or `False` (to match pyjuju)
- int or float: converted to sensible strings
- []string: joined by `\n`s into a single string
- anything else: delegate to FormatYaml
func FormatYaml ¶
FormatYaml marshals value to a yaml-formatted []byte, unless value is nil.
func IsRcPassthroughError ¶
func Main ¶
Main runs the given Command in the supplied Context with the given arguments, which should not include the command name. It returns a code suitable for passing to os.Exit.
func NewCommandLogWriter ¶
NewCommandLogWriter creates a loggo writer for registration by the callers of a command. This way the logged output can also be displayed otherwise, e.g. on the screen.
func NewRcPassthroughError ¶
NewRcPassthroughError creates an error that will have the code used at the return code from the cmd.Main function rather than the default of 1 if there is an error.
func ZeroOrOneArgs ¶
ZeroOrOneArgs checks to see that there are zero or one args, and returns the value of the arg if provided, or the empty string if not.
Types ¶
type AppendStringsValue ¶
type AppendStringsValue []string
AppendStringsValue implements gnuflag.Value for a value that can be set multiple times, and it appends each value to the slice.
func NewAppendStringsValue ¶
func NewAppendStringsValue(target *[]string) *AppendStringsValue
NewAppendStringsValue is used to create the type passed into the gnuflag.FlagSet Var function. f.Var(cmd.NewAppendStringsValue(&someMember), "name", "help")
func (*AppendStringsValue) Set ¶
func (v *AppendStringsValue) Set(s string) error
Implements gnuflag.Value Set.
func (*AppendStringsValue) String ¶
func (v *AppendStringsValue) String() string
Implements gnuflag.Value String.
type Command ¶
type Command interface { // IsSuperCommand returns true if the command is a super command. IsSuperCommand() bool // Info returns information about the Command. Info() *Info // SetFlags adds command specific flags to the flag set. SetFlags(f *gnuflag.FlagSet) // Init initializes the Command before running. Init(args []string) error // Run will execute the Command as directed by the options and positional // arguments passed to Init. Run(ctx *Context) error // AllowInterspersedFlags returns whether the command allows flag // arguments to be interspersed with non-flag arguments. AllowInterspersedFlags() bool }
Command is implemented by types that interpret command-line arguments.
type CommandBase ¶
type CommandBase struct{}
CommandBase provides the default implementation for SetFlags, Init, and Help.
func (*CommandBase) AllowInterspersedFlags ¶
func (c *CommandBase) AllowInterspersedFlags() bool
AllowInterspersedFlags returns true by default. Some subcommands may want to override this.
func (*CommandBase) Init ¶
func (c *CommandBase) Init(args []string) error
Init in the simplest case makes sure there are no args.
func (*CommandBase) IsSuperCommand ¶
func (c *CommandBase) IsSuperCommand() bool
IsSuperCommand implements Command.IsSuperCommand
func (*CommandBase) SetFlags ¶
func (c *CommandBase) SetFlags(f *gnuflag.FlagSet)
SetFlags does nothing in the simplest case.
type Context ¶
type Context struct { Dir string Env map[string]string Stdin io.Reader Stdout io.Writer Stderr io.Writer // contains filtered or unexported fields }
Context represents the run context of a Command. Command implementations should interpret file names relative to Dir (see AbsPath below), and print output and errors to Stdout and Stderr respectively.
func DefaultContext ¶
DefaultContext returns a Context suitable for use in non-hosted situations.
func (*Context) AbsPath ¶
AbsPath returns an absolute representation of path, with relative paths interpreted as relative to ctx.Dir.
func (*Context) Getenv ¶
Getenv looks up an environment variable in the context. It mirrors os.Getenv. An empty string is returned if the key is not set.
func (*Context) Infof ¶
Infof will write the formatted string to Stderr if quiet is false, but if quiet is true the message is logged.
func (*Context) InterruptNotify ¶
InterruptNotify satisfies environs.BootstrapContext
func (*Context) StopInterruptNotify ¶
StopInterruptNotify satisfies environs.BootstrapContext
type DeprecationCheck ¶
type DeprecationCheck interface { // Deprecated aliases emit a warning when executed. If the command is // deprecated, the second return value recommends what to use instead. Deprecated() (bool, string) // Obsolete aliases are not actually registered. The purpose of this // is to allow code to indicate ahead of time some way to determine // that the command should stop working. Obsolete() bool }
DeprecationCheck is used to provide callbacks to determine if a command is deprecated or obsolete.
type FileVar ¶
type FileVar struct { // Path is the path to the file. Path string // StdinMarkers are the Path values that should be interpreted as // stdin. If it is empty then stdin is not supported. StdinMarkers []string }
FileVar represents a path to a file.
func (*FileVar) Open ¶
func (f *FileVar) Open(ctx *Context) (io.ReadCloser, error)
Open opens the file.
type Info ¶
type Info struct { // Name is the Command's name. Name string // Args describes the command's expected positional arguments. Args string // Purpose is a short explanation of the Command's purpose. Purpose string // Doc is the long documentation for the Command. Doc string // Aliases are other names for the Command. Aliases []string }
Info holds some of the usage documentation of a Command.
type Log ¶
type Log struct { // If DefaultConfig is set, it will be used for the // default logging configuration. DefaultConfig string Path string Verbose bool Quiet bool Debug bool ShowLog bool Config string Factory WriterFactory }
Log supplies the necessary functionality for Commands that wish to set up logging.
func (*Log) GetLogWriter ¶
GetLogWriter returns a logging writer for the specified target.
type MissingCallback ¶
MissingCallback defines a function that will be used by the SuperCommand if the requested subcommand isn't found.
type Output ¶
type Output struct {
// contains filtered or unexported fields
}
Output is responsible for interpreting output-related command line flags and writing a value to a file or to stdout as directed.
type RcPassthroughError ¶
type RcPassthroughError struct {
Code int
}
func (*RcPassthroughError) Error ¶
func (e *RcPassthroughError) Error() string
type StringsValue ¶
type StringsValue []string
StringsValue implements gnuflag.Value for a comma separated list of strings. This allows flags to be created where the target is []string, and the caller is after comma separated values.
func NewStringsValue ¶
func NewStringsValue(defaultValue []string, target *[]string) *StringsValue
NewStringsValue is used to create the type passed into the gnuflag.FlagSet Var function. f.Var(cmd.NewStringsValue(defaultValue, &someMember), "name", "help")
func (*StringsValue) String ¶
func (v *StringsValue) String() string
Implements gnuflag.Value String.
type SuperCommand ¶
type SuperCommand struct { CommandBase Name string Purpose string Doc string Log *Log Aliases []string // contains filtered or unexported fields }
SuperCommand is a Command that selects a subcommand and assumes its properties; any command line arguments that were not used in selecting the subcommand are passed down to it, and to Run a SuperCommand is to run its selected subcommand.
func NewSuperCommand ¶
func NewSuperCommand(params SuperCommandParams) *SuperCommand
NewSuperCommand creates and initializes a new `SuperCommand`, and returns the fully initialized structure.
func (*SuperCommand) AddHelpTopic ¶
func (c *SuperCommand) AddHelpTopic(name, short, long string, aliases ...string)
AddHelpTopic adds a new help topic with the description being the short param, and the full text being the long param. The description is shown in 'help topics', and the full text is shown when the command 'help <name>' is called.
func (*SuperCommand) AddHelpTopicCallback ¶
func (c *SuperCommand) AddHelpTopicCallback(name, short string, longCallback func() string)
AddHelpTopicCallback adds a new help topic with the description being the short param, and the full text being defined by the callback function.
func (*SuperCommand) AllowInterspersedFlags ¶
func (c *SuperCommand) AllowInterspersedFlags() bool
For a SuperCommand, we want to parse the args with allowIntersperse=false. This will mean that the args may contain other options that haven't been defined yet, and that only options that relate to the SuperCommand itself can come prior to the subcommand name.
func (*SuperCommand) Info ¶
func (c *SuperCommand) Info() *Info
Info returns a description of the currently selected subcommand, or of the SuperCommand itself if no subcommand has been specified.
func (*SuperCommand) Init ¶
func (c *SuperCommand) Init(args []string) error
Init initializes the command for running.
func (*SuperCommand) IsSuperCommand ¶
func (c *SuperCommand) IsSuperCommand() bool
IsSuperCommand implements Command.IsSuperCommand
func (*SuperCommand) Register ¶
func (c *SuperCommand) Register(subcmd Command)
Register makes a subcommand available for use on the command line. The command will be available via its own name, and via any supplied aliases.
func (*SuperCommand) RegisterAlias ¶
func (c *SuperCommand) RegisterAlias(name, forName string, check DeprecationCheck)
RegisterAlias makes an existing subcommand available under another name. If `check` is supplied, and the result of the `Obsolete` call is true, then the alias is not registered.
func (*SuperCommand) RegisterDeprecated ¶
func (c *SuperCommand) RegisterDeprecated(subcmd Command, check DeprecationCheck)
RegisterDeprecated makes a subcommand available for use on the command line if it is not obsolete. It inserts the command with the specified DeprecationCheck so that a warning is displayed if the command is deprecated.
func (*SuperCommand) RegisterSuperAlias ¶
func (c *SuperCommand) RegisterSuperAlias(name, super, forName string, check DeprecationCheck)
RegisterSuperAlias makes a subcommand of a registered supercommand available under another name. This is useful when the command structure is being refactored. If `check` is supplied, and the result of the `Obsolete` call is true, then the alias is not registered.
func (*SuperCommand) Run ¶
func (c *SuperCommand) Run(ctx *Context) error
Run executes the subcommand that was selected in Init.
func (*SuperCommand) SetCommonFlags ¶
func (c *SuperCommand) SetCommonFlags(f *gnuflag.FlagSet)
SetCommonFlags creates a new "commonflags" flagset, whose flags are shared with the argument f; this enables us to add non-global flags to f, which do not carry into subcommands.
func (*SuperCommand) SetFlags ¶
func (c *SuperCommand) SetFlags(f *gnuflag.FlagSet)
SetFlags adds the options that apply to all commands, particularly those due to logging.
type SuperCommandParams ¶
type SuperCommandParams struct { // UsagePrefix should be set when the SuperCommand is // actually a subcommand of some other SuperCommand; // if NotifyRun is called, it name will be prefixed accordingly, // unless UsagePrefix is identical to Name. UsagePrefix string // Notify, if not nil, is called when the SuperCommand // is about to run a sub-command. NotifyRun func(cmdName string) Name string Purpose string Doc string Log *Log MissingCallback MissingCallback Aliases []string Version string }
SuperCommandParams provides a way to have default parameter to the `NewSuperCommand` call.
type UnrecognizedCommand ¶
type UnrecognizedCommand struct {
Name string
}
func (*UnrecognizedCommand) Error ¶
func (e *UnrecognizedCommand) Error() string