app: Add a global -q/--quiet flag

This replaces the need for `StandardOutput=null` in the automatic
upgrade unit, and can also be used for custom upgrade units, such
as that proposed in
coreos/fedora-coreos-docs#540

src/app/libmain.cxx

@@ -128,13 +128,16 @@ static RpmOstreeCommand commands[] = {
 };
 
 static gboolean opt_version;
+static gboolean opt_quiet;
 static gboolean opt_force_peer;
 static char *opt_sysroot;
 static gchar **opt_install;
 static gchar **opt_uninstall;
 
 static GOptionEntry global_entries[] = { { "version", 0, 0, G_OPTION_ARG_NONE, &opt_version,
                                            "Print version information and exit", NULL },
+                                         { "quiet", 'q', 0, G_OPTION_ARG_NONE, &opt_quiet,
+                                           "Avoid printing most informational messages", NULL },
                                          { NULL } };
 
 static GOptionEntry daemon_entries[]
@@ -211,6 +214,13 @@ client_throw_non_ostree_host_error (GError **error)
 
 } /* namespace */
 
+// Returns TRUE if the global quiet flag was specified
+bool
+rpmostree_global_quiet (void)
+{
+  return opt_quiet;
+}
+
 gboolean
 rpmostree_option_context_parse (GOptionContext *context, const GOptionEntry *main_entries,
                                 int *argc, char ***argv, RpmOstreeCommandInvocation *invocation,

src/app/rpmostree-builtins.h

@@ -63,6 +63,8 @@ BUILTINPROTO (initramfs_etc);
 
 #undef BUILTINPROTO
 
+bool rpmostree_global_quiet (void);
+
 gboolean rpmostree_option_context_parse (GOptionContext *context, const GOptionEntry *main_entries,
                                          int *argc, char ***argv,
                                          RpmOstreeCommandInvocation *invocation,

src/app/rpmostree-clientlib.cxx

@@ -326,6 +326,30 @@ on_transaction_progress (GDBusProxy *proxy, gchar *sender_name, gchar *signal_na
 
   g_debug ("txn progress %s", signal_name);
 
+  if (g_strcmp0 (signal_name, "Finished") == 0)
+    {
+      if (tp->error == NULL)
+        {
+          g_autofree char *error_message = NULL;
+          gboolean success = FALSE;
+
+          g_variant_get (parameters, "(bs)", &success, &error_message);
+
+          if (!success)
+            {
+              tp->error = g_dbus_error_new_for_dbus_error (
+                  "org.projectatomic.rpmostreed.Error.Failed", error_message);
+            }
+        }
+
+      transaction_progress_end (tp);
+      return;
+    }
+
+  // Everything else below here is just printing progress, which we suppress in quiet mode
+  if (rpmostree_global_quiet ())
+    return;
+
   if (g_strcmp0 (signal_name, "SignatureProgress") == 0)
     {
       /* We used to print the signature here, but doing so interferes with the
@@ -390,24 +414,6 @@ on_transaction_progress (GDBusProxy *proxy, gchar *sender_name, gchar *signal_na
       else
         rpmostreecxx::console_progress_set_message (line.c_str ());
     }
-  else if (g_strcmp0 (signal_name, "Finished") == 0)
-    {
-      if (tp->error == NULL)
-        {
-          g_autofree char *error_message = NULL;
-          gboolean success = FALSE;
-
-          g_variant_get (parameters, "(bs)", &success, &error_message);
-
-          if (!success)
-            {
-              tp->error = g_dbus_error_new_for_dbus_error (
-                  "org.projectatomic.rpmostreed.Error.Failed", error_message);
-            }
-        }
-
-      transaction_progress_end (tp);
-    }
 }
 
 static void

src/daemon/rpm-ostreed-automatic.service

@@ -5,5 +5,4 @@ ConditionPathExists=/run/ostree-booted
 
 [Service]
 Type=simple
-ExecStart=rpm-ostree upgrade --trigger-automatic-update-policy
-StandardOutput=null
+ExecStart=rpm-ostree upgrade --quiet --trigger-automatic-update-policy