[minor/bug] fix module parameter input issues

This resolves a bug introduced in e2e687f. The args parameter to
runModuleDirectly() used to contain input parameters, but as of recent
changes to allow parameters via stdin does not.

Since the parameter was unused, this changes it to be an interface
pointer. If set, this will be used as module parameters, if not the
agent modules will expect input via stdin as normal.

mig-agent/agent.go

@@ -6,6 +6,7 @@
 package main
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/json"
 	"flag"
@@ -131,12 +132,7 @@ func main() {
 			panic(err)
 		}
 	default:
-		var tmparg string
-		for _, arg := range flag.Args() {
-			tmparg = tmparg + arg
-		}
-		args := []byte(tmparg)
-		fmt.Printf("%s", runModuleDirectly(*mode, args, *pretty))
+		fmt.Printf("%s", runModuleDirectly(*mode, nil, *pretty))
 	}
 exit:
 }
@@ -191,17 +187,27 @@ func executeAction(action mig.Action, prettyPrint bool) (cmd mig.Command, err er
 }
 
 // runModuleDirectly executes a module and displays the results on stdout
-func runModuleDirectly(mode string, args interface{}, pretty bool) (out string) {
+//
+// paramargs allows the parameters to be specified as an argument to the
+// function, overriding the expectation parameters will be sent via
+// Stdin. If nil, the parameters will still be read on Stdin by the module.
+func runModuleDirectly(mode string, paramargs interface{}, pretty bool) (out string) {
 	if _, ok := modules.Available[mode]; !ok {
 		return fmt.Sprintf(`{"errors": ["module '%s' is not available"]}`, mode)
 	}
-	// instanciate and call module
-	run := modules.Available[mode].NewRun()
-	msg, err := modules.MakeMessage(modules.MsgClassParameters, args)
-	if err != nil {
-		panic(err)
+	infd := bufio.NewReader(os.Stdin)
+	// If parameters are being supplied as an argument, use these vs.
+	// expecting parameters to be supplied on Stdin.
+	if paramargs != nil {
+		msg, err := modules.MakeMessage(modules.MsgClassParameters, paramargs)
+		if err != nil {
+			panic(err)
+		}
+		infd = bufio.NewReader(bytes.NewBuffer(msg))
 	}
-	out = run.Run(bytes.NewBuffer(msg))
+	// instantiate and call module
+	run := modules.Available[mode].NewRun()
+	out = run.Run(infd)
 	if pretty {
 		var modres modules.Result
 		err := json.Unmarshal([]byte(out), &modres)