Handling of redirected input (#3451)

* User input forwarding

* Shell cleanup

* Errors update

* Added error checking

* imports update

* Improved error checking

shell/ptty_unix.go

@@ -71,12 +71,17 @@ func runCommandWithPTTY(terragruntOptions *options.TerragruntOptions, cmd *exec.
 		}
 	}()
 
+	stdinDone := make(chan error, 1)
 	// Copy stdin to the pty
 	go func() {
 		_, copyStdinErr := io.Copy(pseudoTerminal, os.Stdin)
 		// We don't propagate this error upstream because it does not affect normal operation of the command. A repeat
 		// of the same stdin in this case should resolve the issue.
-		terragruntOptions.Logger.Errorf("Error forwarding stdin: %s", copyStdinErr)
+		if copyStdinErr != nil {
+			terragruntOptions.Logger.Errorf("Error forwarding stdin: %s", copyStdinErr)
+		}
+		// signal that stdin copy is done
+		stdinDone <- copyStdinErr
 	}()
 
 	// ... and the pty to stdout.
@@ -85,6 +90,12 @@ func runCommandWithPTTY(terragruntOptions *options.TerragruntOptions, cmd *exec.
 		return errors.WithStackTrace(copyStdoutErr)
 	}
 
+	// Wait for stdin copy to complete before returning
+
+	if copyStdinErr := <-stdinDone; copyStdinErr != nil && !errors.IsError(copyStdinErr, io.EOF) {
+		terragruntOptions.Logger.Errorf("Error forwarding stdin: %s", copyStdinErr)
+	}
+
 	return nil
 }
 

shell/run_shell_cmd.go

@@ -14,6 +14,8 @@ import (
 	"strings"
 	"time"
 
+	"github.com/mattn/go-isatty"
+
 	"github.com/gruntwork-io/terragrunt/internal/cache"
 
 	"github.com/gruntwork-io/terragrunt/engine"
@@ -293,6 +295,11 @@ func isTerraformCommandThatNeedsPty(args []string) (bool, error) {
 		return false, nil
 	}
 
+	// if the stdin is not a terminal, then the terraform console is used in non-interactive mode
+	if !isatty.IsTerminal(os.Stdin.Fd()) {
+		return false, nil
+	}
+
 	return true, nil
 }