Merge pull request #680 from noxer/master

Make the cmdrunner more interactive

modules/cmdrunner/settings.go

@@ -7,24 +7,30 @@ import (
 )
 
 const (
- defaultFocusable = false
+ defaultFocusable = true
  defaultTitle = "CmdRunner"
 )
 
+// Settings for the cmdrunner widget
 type Settings struct {
  common *cfg.Common
 
- args []string `help:"The arguments to the command, with each item as an element in an array. Example: for curl -I cisco.com, the arguments array would be ['-I', 'cisco.com']."`
- cmd string `help:"The terminal command to be run, withouth the arguments. Ie: ping, whoami, curl."`
+ args []string `help:"The arguments to the command, with each item as an element in an array. Example: for curl -I cisco.com, the arguments array would be ['-I', 'cisco.com']."`
+ cmd string `help:"The terminal command to be run, withouth the arguments. Ie: ping, whoami, curl."`
+ tail bool `help:"Automatically scroll to the end of the command output."`
+ maxLines int `help:"Maximum number of lines kept in the buffer."`
 }
 
+// NewSettingsFromYAML loads the cmdrunner portion of the WTF config
 func NewSettingsFromYAML(name string, moduleConfig *config.Config, globalConfig *config.Config) *Settings {
 
  settings := Settings{
  common: cfg.NewCommonSettingsFromModule(name, defaultTitle, defaultFocusable, moduleConfig, globalConfig),
 
- args: utils.ToStrs(moduleConfig.UList("args")),
- cmd: moduleConfig.UString("cmd"),
+ args: utils.ToStrs(moduleConfig.UList("args")),
+ cmd: moduleConfig.UString("cmd"),
+ tail: moduleConfig.UBool("tail"),
+ maxLines: moduleConfig.UInt("maxLines", 256),
  }
 
  return &settings

modules/cmdrunner/widget.go

@@ -1,40 +1,44 @@
 package cmdrunner
 
 import (
+ "bytes"
  "fmt"
  "os/exec"
  "strings"
+ "sync"
 
  "github.com/rivo/tview"
- "github.com/wtfutil/wtf/utils"
  "github.com/wtfutil/wtf/view"
 )
 
+// Widget contains the data for this widget
 type Widget struct {
  view.TextWidget
 
- args []string
- cmd string
  settings *Settings
+
+ m sync.Mutex
+ buffer *bytes.Buffer
+ running bool
 }
 
 // NewWidget creates a new instance of the widget
 func NewWidget(app *tview.Application, settings *Settings) *Widget {
  widget := Widget{
  TextWidget: view.NewTextWidget(app, settings.common),
 
- args: settings.args,
- cmd: settings.cmd,
  settings: settings,
+ buffer: &bytes.Buffer{},
  }
 
  widget.View.SetWrap(true)
+ widget.View.SetScrollable(true)
 
  return &widget
 }
 
 func (widget *Widget) content() (string, string, bool) {
- result := widget.execute()
+ result := widget.buffer.String()
 
  ansiTitle := tview.TranslateANSI(widget.CommonSettings().Title)
  if ansiTitle == defaultTitle {
@@ -47,23 +51,86 @@ func (widget *Widget) content() (string, string, bool) {
 
 // Refresh executes the command and updates the view with the results
 func (widget *Widget) Refresh() {
+ widget.m.Lock()
+ defer widget.m.Unlock()
+
+ widget.execute()
  widget.Redraw(widget.content)
+ if widget.settings.tail {
+ widget.View.ScrollToEnd()
+ }
 }
 
 // String returns the string representation of the widget
 func (widget *Widget) String() string {
- args := strings.Join(widget.args, " ")
+ args := strings.Join(widget.settings.args, " ")
 
  if args != "" {
- return fmt.Sprintf(" %s %s ", widget.cmd, args)
+ return fmt.Sprintf(" %s %s ", widget.settings.cmd, args)
  }
 
- return fmt.Sprintf(" %s ", widget.cmd)
+ return fmt.Sprintf(" %s ", widget.settings.cmd)
+}
+
+func (widget *Widget) Write(p []byte) (n int, err error) {
+ widget.m.Lock()
+ defer widget.m.Unlock()
+
+ // Write the new data into the buffer
+ n, err = widget.buffer.Write(p)
+
+ // Remove lines that exceed maxLines
+ lines := widget.countLines()
+ if lines > widget.settings.maxLines {
+ widget.drainLines(lines - widget.settings.maxLines)
+ }
+
+ // Redraw the widget
+ widget.Redraw(widget.content)
+
+ return
 }
 
 /* -------------------- Unexported Functions -------------------- */
 
-func (widget *Widget) execute() string {
- cmd := exec.Command(widget.cmd, widget.args...)
- return utils.ExecuteCommand(cmd)
+func (widget *Widget) execute() {
+ // Make sure the command is not already running
+ if widget.running {
+ return
+ }
+
+ // Reset the buffer
+ widget.buffer.Reset()
+
+ // Indicate that the command is running
+ widget.running = true
+
+ // Setup the command to run
+ cmd := exec.Command(widget.settings.cmd, widget.settings.args...)
+ cmd.Stdout = widget
+
+ // Run the command and wait for it to exit in another Go-routine
+ go func() {
+ err := cmd.Run()
+
+ // The command has exited, print any error messages
+ widget.m.Lock()
+ if err != nil {
+ widget.buffer.WriteString(err.Error())
+ }
+ widget.running = false
+ widget.m.Unlock()
+ }()
+}
+
+// countLines counts the lines of data in the buffer
+func (widget *Widget) countLines() int {
+ return bytes.Count(widget.buffer.Bytes(), []byte{'\n'})
+}
+
+// drainLines removed the first n lines from the buffer
+func (widget *Widget) drainLines(n int) {
+ for i := 0; i < n; i++ {
+ widget.buffer.ReadBytes('\n')
+ }
 }