[CORE-1231] pass pachctl args to server for audit logging (#8356)

* send args in metadata

* log user commands

src/client/client.go

@@ -858,6 +858,9 @@ func (c *APIClient) AddMetadata(ctx context.Context) context.Context {
 		clientData["userid"] = c.metricsUserID
 		clientData["prefix"] = c.metricsPrefix
 	}
+	if len(os.Args) > 1 && os.Args[0] != "/pachd" {
+		clientData["command"] = strings.Join(os.Args, " ")
+	}
 
 	// Rescue any metadata pairs already in 'ctx' (otherwise
 	// metadata.NewOutgoingContext() would drop them). Note that this is similar

src/internal/middleware/logging/interceptor.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"reflect"
+	"strings"
 	"time"
 
 	"github.com/gogo/protobuf/types"
@@ -382,6 +383,12 @@ func (li *LoggingInterceptor) UnaryServerInterceptor(ctx context.Context, req in
 		logReq = config.transformRequest(req)
 	}
 
+	md, ok := metadata.FromIncomingContext(ctx)
+	if ok && len(md.Get("command")) > 0 {
+		command := md.Get("command")
+		li.logger.Logf(logrus.InfoLevel, "user command: %s", strings.Join(command, ""))
+	}
+
 	li.logUnaryBefore(ctx, level, logReq, info.FullMethod, start)
 	defer func() {
 		level := defaultLevel(retErr)