Add `--pretty` option to mosquitto_sub/rr

If active, this produces formatted JSON output rather than the normal
minimised output.

ChangeLog.txt

@@ -24,6 +24,8 @@ Clients:
 - Use cJSON library for producing JSON output, where available. Closes #1222.
 - Add support for outputting MQTT v5 property information to mosquitto_sub/rr
   JSON output.
+- Add `--pretty` option to mosquitto_sub/rr for formatted/unformatted JSON
+  output.
 
 
 1.6.7 - 20190925

client/client_shared.c

@@ -748,6 +748,11 @@ int client_config_line_proc(struct mosq_config *cfg, int pub_or_sub, int argc, c
 				}
 			}
 			i++;
+		}else if(!strcmp(argv[i], "--pretty")){
+			if(pub_or_sub == CLIENT_PUB){
+				goto unknown_option;
+			}
+			cfg->pretty = true;
 		}else if(!strcmp(argv[i], "-P") || !strcmp(argv[i], "--pw")){
 			if(i==argc-1){
 				fprintf(stderr, "Error: -P argument given but no password specified.\n\n");

client/client_shared.h

@@ -89,8 +89,8 @@ struct mosq_config {
 #  endif
 #endif
 	bool clean_session;
-	char **topics; /* sub */
+	char **topics; /* sub, rr */
-	int topic_count; /* sub */
+	int topic_count; /* sub, rr */
 	bool exit_after_sub; /* sub */
 	bool no_retain; /* sub */
 	bool retained_only; /* sub */
@@ -102,7 +102,8 @@ struct mosq_config {
 	bool verbose; /* sub */
 	bool eol; /* sub */
 	int msg_count; /* sub */
-	char *format; /* sub */
+	char *format; /* sub, rr */
+	bool pretty; /* sub, rr */
 	int timeout; /* sub */
 	int sub_opts; /* sub */
 #ifdef WITH_SOCKS

client/rr_client.c

@@ -217,6 +217,8 @@ void print_usage(void)
 	printf(" -W : Specifies a timeout in seconds how long to wait for a response.\n");
 #endif
 	printf(" --help : display this message.\n");
+	printf(" --pretty : print formatted output rather than minimised output when using the\n");
+	printf("            JSON output format option.\n");
 	printf(" --quiet : don't print error messages.\n");
 	printf(" --unix : connect to a broker through a unix domain socket instead of a TCP socket,\n");
 	printf("          e.g. /tmp/mosquitto.sock\n");

client/sub_client.c

@@ -238,6 +238,8 @@ void print_usage(void)
 	printf(" -W : Specifies a timeout in seconds how long to process incoming MQTT messages.\n");
 #endif
 	printf(" --help : display this message.\n");
+	printf(" --pretty : print formatted output rather than minimised output when using the\n");
+	printf("            JSON output format option.\n");
 	printf(" --quiet : don't print error messages.\n");
 	printf(" --retained-only : only handle messages with the retained flag set, and exit when the\n");
 	printf("                   first non-retained message is received.\n");

client/sub_client_output.c

@@ -208,7 +208,7 @@ static int json_print_properties(cJSON *root, const mosquitto_property *properti
 #endif
 
 
-static int json_print(const struct mosquitto_message *message, const mosquitto_property *properties, const struct tm *ti, bool escaped)
+static int json_print(const struct mosquitto_message *message, const mosquitto_property *properties, const struct tm *ti, bool escaped, bool pretty)
 {
 #ifdef WITH_CJSON
 	cJSON *root;
@@ -292,8 +292,11 @@ static int json_print(const struct mosquitto_message *message, const mosquitto_p
 		cJSON_AddItemToObject(root, "payload", tmp);
 	}
 
-	//json_str = cJSON_PrintUnformatted(root);
+	if(pretty){
 		json_str = cJSON_Print(root);
+	}else{
+		json_str = cJSON_PrintUnformatted(root);
+	}
 	cJSON_Delete(root);
 
 	fputs(json_str, stdout);
@@ -363,7 +366,7 @@ static void formatted_print(const struct mosq_config *lcfg, const struct mosquit
 								return;
 							}
 						}
-						if(json_print(message, properties, ti, true) != MOSQ_ERR_SUCCESS){
+						if(json_print(message, properties, ti, true, lcfg->pretty) != MOSQ_ERR_SUCCESS){
 							err_printf(lcfg, "Error: Out of memory.\n");
 							return;
 						}
@@ -376,7 +379,7 @@ static void formatted_print(const struct mosq_config *lcfg, const struct mosquit
 								return;
 							}
 						}
-						rc = json_print(message, properties, ti, false);
+						rc = json_print(message, properties, ti, false, lcfg->pretty);
 						if(rc == MOSQ_ERR_NOMEM){
 							err_printf(lcfg, "Error: Out of memory.\n");
 							return;

man/mosquitto_rr.1.xml

@@ -46,6 +46,7 @@
 			<arg><option>-I</option> <replaceable>client-id-prefix</replaceable></arg>
 			<arg><option>-k</option> <replaceable>keepalive-time</replaceable></arg>
 			<arg><option>-N</option></arg>
+			<arg><option>--pretty</option></arg>
 			<arg><option>-q</option> <replaceable>message-QoS</replaceable></arg>
 			<arg><option>-R</option></arg>
 			<arg><option>-S</option></arg>
@@ -396,6 +397,16 @@
 						See also the <option>--username</option> option.</para>
 				</listitem>
 			</varlistentry>
+			<varlistentry>
+				<term><option>--pretty</option></term>
+				<listitem>
+                    <para>
+						When using the JSON output format %j or %J, the default
+						is to print in an unformatted fashion. Specifying
+						<option>--pretty</option> prints messages in a prettier,
+						more human readable format.</para>
+				</listitem>
+			</varlistentry>
 			<varlistentry>
 				<term><option>--proxy</option></term>
 				<listitem>

man/mosquitto_sub.1.xml

@@ -41,6 +41,7 @@
 			<arg><option>-I</option> <replaceable>client-id-prefix</replaceable></arg>
 			<arg><option>-k</option> <replaceable>keepalive-time</replaceable></arg>
 			<arg><option>-N</option></arg>
+			<arg><option>--pretty</option></arg>
 			<arg><option>-q</option> <replaceable>message-QoS</replaceable></arg>
 			<arg><option>--remove-retained</option></arg>
 			<group choice='opt'>
@@ -405,6 +406,16 @@
 						See also the <option>--username</option> option.</para>
 				</listitem>
 			</varlistentry>
+			<varlistentry>
+				<term><option>--pretty</option></term>
+				<listitem>
+                    <para>
+						When using the JSON output format %j or %J, the default
+						is to print in an unformatted fashion. Specifying
+						<option>--pretty</option> prints messages in a prettier,
+						more human readable format.</para>
+				</listitem>
+			</varlistentry>
 			<varlistentry>
 				<term><option>--proxy</option></term>
 				<listitem>