Merge pull request #2527 from abiliojr/test_config

broker: add command line argument to test configuration and exit

ChangeLog.txt

@@ -55,6 +55,8 @@ Broker:
 - Bridge reconnection backoff improvements.
 - Add bridge_tls_use_os_certs option to allow bridges to be easily configured
   to trust default CA certificates. Closes #2473.
+- Add `--test-config` option which can be used to test a configuration file
+  before trying to use it in a live broker. Closes #2521.
 
 Plugins / plugin interface:
 - Add persist-sqlite plugin.

src/conf.c

@@ -387,9 +387,10 @@ static void print_usage(void)
 	printf("      Not recommended in conjunction with the -c option.\n");
 	printf(" -v : verbose mode - enable all logging types. This overrides\n");
 	printf("      any logging options given in the config file.\n");
-	printf(" --tls-keylog : Log TLS connection information to a file, to allow\n");
+	printf(" --tls-keylog : log TLS connection information to a file, to allow\n");
 	printf("      debugging with e.g. wireshark. Do not use on a production\n");
 	printf("      server.\n");
+	printf(" --test-config : test config file and exit\n");
 	printf("\nSee https://mosquitto.org/ for more information.\n\n");
 }
 
@@ -454,6 +455,8 @@ int config__parse_args(struct mosquitto__config *config, int argc, char *argv[])
 #endif
 		}else if(!strcmp(argv[i], "-v") || !strcmp(argv[i], "--verbose")){
 			db.verbose = true;
+		}else if(!strcmp(argv[i], "--test-config")){
+			config->test_configuration = true;
 		}else{
 			fprintf(stderr, "Error: Unknown option '%s'.\n",argv[i]);
 			print_usage();

src/mosquitto.c

@@ -264,6 +264,16 @@ int main(int argc, char *argv[])
 	rc = config__parse_args(&config, argc, argv);
 	if(rc != MOSQ_ERR_SUCCESS) return rc;
 
+	if(config.test_configuration){
+		if(!db.config_file){
+			log__printf(NULL, MOSQ_LOG_ERR, "Please provide a configuration file to test.");
+			return MOSQ_ERR_INVAL;
+		}else{
+			log__printf(NULL, MOSQ_LOG_INFO, "Configuration file is OK.");
+			return MOSQ_ERR_SUCCESS;
+		}
+	}
+
 	rc = keepalive__init();
 	if(rc != MOSQ_ERR_SUCCESS) return rc;
 

src/mosquitto_broker_internal.h

@@ -306,6 +306,7 @@ struct mosquitto__config {
 	uint16_t cmd_port[CMD_PORT_LIMIT];
 	int cmd_port_count;
 	bool daemon;
+	bool test_configuration;
 	bool enable_control_api;
 	int global_max_clients;
 	int global_max_connections;