From 2a256d4c5397fb0e91ab71cc73787698d13023e0 Mon Sep 17 00:00:00 2001 From: Matt Farina Date: Thu, 5 May 2016 10:26:53 -0400 Subject: [PATCH 1/2] Provide a variable for writing output with a default of os.Stderr --- app.go | 6 +++--- errors.go | 6 +++++- flag.go | 2 +- help.go | 2 +- 4 files changed, 10 insertions(+), 6 deletions(-) diff --git a/app.go b/app.go index 89c741b..28bf78b 100644 --- a/app.go +++ b/app.go @@ -228,11 +228,11 @@ func (a *App) Run(arguments []string) (err error) { // DEPRECATED: Another entry point to the cli app, takes care of passing arguments and error handling func (a *App) RunAndExitOnError() { - fmt.Fprintf(os.Stderr, + fmt.Fprintf(OutWriter, "DEPRECATED cli.App.RunAndExitOnError. %s See %s\n", contactSysadmin, runAndExitOnErrorDeprecationURL) if err := a.Run(os.Args); err != nil { - fmt.Fprintln(os.Stderr, err) + fmt.Fprintln(OutWriter, err) OsExiter(1) } } @@ -422,7 +422,7 @@ func HandleAction(action interface{}, context *Context) (err error) { vals := reflect.ValueOf(action).Call([]reflect.Value{reflect.ValueOf(context)}) if len(vals) == 0 { - fmt.Fprintf(os.Stderr, + fmt.Fprintf(OutWriter, "DEPRECATED Action signature. Must be `cli.ActionFunc`. %s See %s\n", contactSysadmin, appActionDeprecationURL) return nil diff --git a/errors.go b/errors.go index 5f1e83b..c03e676 100644 --- a/errors.go +++ b/errors.go @@ -8,6 +8,10 @@ import ( var OsExiter = os.Exit +// OutWriter is used to write output to the user. This can be anything +// implementing the io.Writer interface and defaults to os.Stderr. +var OutWriter = os.Stderr + type MultiError struct { Errors []error } @@ -69,7 +73,7 @@ func HandleExitCoder(err error) { if exitErr, ok := err.(ExitCoder); ok { if err.Error() != "" { - fmt.Fprintln(os.Stderr, err) + fmt.Fprintln(OutWriter, err) } OsExiter(exitErr.ExitCode()) return diff --git a/flag.go b/flag.go index 3b6a2e1..7778a2d 100644 --- a/flag.go +++ b/flag.go @@ -220,7 +220,7 @@ func (f IntSliceFlag) Apply(set *flag.FlagSet) { s = strings.TrimSpace(s) err := newVal.Set(s) if err != nil { - fmt.Fprintf(os.Stderr, err.Error()) + fmt.Fprintf(OutWriter, err.Error()) } } f.Value = newVal diff --git a/help.go b/help.go index 45e8603..79f2e85 100644 --- a/help.go +++ b/help.go @@ -188,7 +188,7 @@ func printHelp(out io.Writer, templ string, data interface{}) { err := t.Execute(w, data) if err != nil { // If the writer is closed, t.Execute will fail, and there's nothing - // we can do to recover. We could send this to os.Stderr if we need. + // we can do to recover. We could send this to OutWriter if we need. return } w.Flush() From 6f0b442222239d0c6c6a999742e6d56b58494d7e Mon Sep 17 00:00:00 2001 From: Matt Farina Date: Fri, 6 May 2016 12:14:26 -0400 Subject: [PATCH 2/2] Update to ErrWriter and make available on app --- app.go | 18 +++++++++++++++--- errors.go | 7 ++++--- flag.go | 2 +- help.go | 2 +- 4 files changed, 21 insertions(+), 8 deletions(-) diff --git a/app.go b/app.go index 28bf78b..4d18d24 100644 --- a/app.go +++ b/app.go @@ -82,6 +82,8 @@ type App struct { Email string // Writer writer to write output to Writer io.Writer + // ErrWriter writes error output + ErrWriter io.Writer // Other custom info Metadata map[string]interface{} } @@ -228,11 +230,11 @@ func (a *App) Run(arguments []string) (err error) { // DEPRECATED: Another entry point to the cli app, takes care of passing arguments and error handling func (a *App) RunAndExitOnError() { - fmt.Fprintf(OutWriter, + fmt.Fprintf(a.errWriter(), "DEPRECATED cli.App.RunAndExitOnError. %s See %s\n", contactSysadmin, runAndExitOnErrorDeprecationURL) if err := a.Run(os.Args); err != nil { - fmt.Fprintln(OutWriter, err) + fmt.Fprintln(a.errWriter(), err) OsExiter(1) } } @@ -377,6 +379,16 @@ func (a *App) hasFlag(flag Flag) bool { return false } +func (a *App) errWriter() io.Writer { + + // When the app ErrWriter is nil use the package level one. + if a.ErrWriter == nil { + return ErrWriter + } + + return a.ErrWriter +} + func (a *App) appendFlag(flag Flag) { if !a.hasFlag(flag) { a.Flags = append(a.Flags, flag) @@ -422,7 +434,7 @@ func HandleAction(action interface{}, context *Context) (err error) { vals := reflect.ValueOf(action).Call([]reflect.Value{reflect.ValueOf(context)}) if len(vals) == 0 { - fmt.Fprintf(OutWriter, + fmt.Fprintf(ErrWriter, "DEPRECATED Action signature. Must be `cli.ActionFunc`. %s See %s\n", contactSysadmin, appActionDeprecationURL) return nil diff --git a/errors.go b/errors.go index c03e676..db46a83 100644 --- a/errors.go +++ b/errors.go @@ -2,15 +2,16 @@ package cli import ( "fmt" + "io" "os" "strings" ) var OsExiter = os.Exit -// OutWriter is used to write output to the user. This can be anything +// ErrWriter is used to write errors to the user. This can be anything // implementing the io.Writer interface and defaults to os.Stderr. -var OutWriter = os.Stderr +var ErrWriter io.Writer = os.Stderr type MultiError struct { Errors []error @@ -73,7 +74,7 @@ func HandleExitCoder(err error) { if exitErr, ok := err.(ExitCoder); ok { if err.Error() != "" { - fmt.Fprintln(OutWriter, err) + fmt.Fprintln(ErrWriter, err) } OsExiter(exitErr.ExitCode()) return diff --git a/flag.go b/flag.go index 7778a2d..8354de0 100644 --- a/flag.go +++ b/flag.go @@ -220,7 +220,7 @@ func (f IntSliceFlag) Apply(set *flag.FlagSet) { s = strings.TrimSpace(s) err := newVal.Set(s) if err != nil { - fmt.Fprintf(OutWriter, err.Error()) + fmt.Fprintf(ErrWriter, err.Error()) } } f.Value = newVal diff --git a/help.go b/help.go index 79f2e85..f4ea7a3 100644 --- a/help.go +++ b/help.go @@ -188,7 +188,7 @@ func printHelp(out io.Writer, templ string, data interface{}) { err := t.Execute(w, data) if err != nil { // If the writer is closed, t.Execute will fail, and there's nothing - // we can do to recover. We could send this to OutWriter if we need. + // we can do to recover. We could send this to ErrWriter if we need. return } w.Flush()