message.c: Add option to suppress the Message channel AMI and ARI events

In order to reduce the amount of AMI and ARI events generated,
the global "Message/ast_msg_queue" channel can be set to suppress
it's normal channel housekeeping events such as "Newexten",
"VarSet", etc. This can greatly reduce load on the manager
and ARI applications when the Digium Phone Module for Asterisk
is in use.  To enable, set "hide_messaging_ami_events" in
asterisk.conf to "yes"  In Asterisk versions <18, the default
is "no" preserving existing behavior.  Beginning with
Asterisk 18, the option will default to "yes".

NOTE:  This change does not affect UserEvents or the ARI
TextMessageReceived events.

* Added the "hide_messaging_ami_events" option to asterisk.conf.

* Changed message.c to set the AST_CHAN_TP_INTERNAL property on
  the "Message/ast_msg_queue" channel if the option is set in
  asterisk.conf.  This suppresses the reporting of the events.

Change-Id: Ia2e3516d43f4e0df994fc6598565d6bba2d7018b

configs/samples/asterisk.conf.sample

@@ -118,6 +118,11 @@ documentation_language = en_US	; Set the language you want documentation
 				; calls are not accepted by a remote
 				; implementation, please report this and go
 				; back to value 96.
+;hide_messaging_ami_events = no;  This option, if enabled, will
+                ; suppress all of the Message/ast_msg_queue channel's
+                ; housekeeping AMI and ARI channel events.  This can
+                ; reduce the load on the manager and ARI applications
+                ; when the Digium Phone Module for Asterisk is in use.
 
 ; Changing the following lines may compromise your security.
 ;[files]

doc/CHANGES-staging/hide_messaging_ami_events

@@ -0,0 +1,11 @@
+Subject: Messaging
+
+In order to reduce the amount of AMI and ARI events generated,
+the global "Message/ast_msg_queue" channel can be set to suppress
+it's normal channel housekeeping events such as "Newexten",
+"VarSet", etc. This can greatly reduce load on the manager
+and ARI applications when the Digium Phone Module for Asterisk
+is in use.  To enable, set "hide_messaging_ami_events" in
+asterisk.conf to "yes"  In Asterisk versions <18, the default
+is "no" preserving existing behavior.  Beginning with
+Asterisk 18, the option will default to "yes".

include/asterisk/options.h

@@ -84,6 +84,8 @@ enum ast_option_flags {
 	AST_OPT_FLAG_DEBUG_MODULE = (1 << 23),
 	/*! Terminal colors should be adjusted for a light-colored background */
 	AST_OPT_FLAG_LIGHT_BACKGROUND = (1 << 25),
+	/*! Make the global Message channel an internal channel to suppress AMI events */
+	AST_OPT_FLAG_HIDE_MESSAGING_AMI_EVENTS = (1 << 26),
 	/*! Force black background */
 	AST_OPT_FLAG_FORCE_BLACK_BACKGROUND = (1 << 27),
 	/*! Hide remote console connect messages on console */
@@ -129,6 +131,7 @@ enum ast_option_flags {
 #define ast_opt_generic_plc         ast_test_flag(&ast_options, AST_OPT_FLAG_GENERIC_PLC)
 #define ast_opt_ref_debug           ast_test_flag(&ast_options, AST_OPT_FLAG_REF_DEBUG)
 #define ast_opt_generic_plc_on_equal_codecs  ast_test_flag(&ast_options, AST_OPT_FLAG_GENERIC_PLC_ON_EQUAL_CODECS)
+#define ast_opt_hide_messaging_ami_events  ast_test_flag(&ast_options, AST_OPT_FLAG_HIDE_MESSAGING_AMI_EVENTS)
 
 /*! Maximum log level defined by PJPROJECT. */
 #define MAX_PJ_LOG_MAX_LEVEL		6

main/asterisk.c

@@ -509,6 +509,7 @@ static char *handle_show_settings(struct ast_cli_entry *e, int cmd, struct ast_c
 	ast_cli(a->fd, "  Transmit silence during rec: %s\n", ast_test_flag(&ast_options, AST_OPT_FLAG_TRANSMIT_SILENCE) ? "Enabled" : "Disabled");
 	ast_cli(a->fd, "  Generic PLC:                 %s\n", ast_test_flag(&ast_options, AST_OPT_FLAG_GENERIC_PLC) ? "Enabled" : "Disabled");
 	ast_cli(a->fd, "  Generic PLC on equal codecs: %s\n", ast_test_flag(&ast_options, AST_OPT_FLAG_GENERIC_PLC_ON_EQUAL_CODECS) ? "Enabled" : "Disabled");
+	ast_cli(a->fd, "  Hide Msg Chan AMI events:    %s\n", ast_opt_hide_messaging_ami_events ? "Enabled" : "Disabled");
 	ast_cli(a->fd, "  Min DTMF duration::          %u\n", option_dtmfminduration);
 #if !defined(LOW_MEMORY)
 	ast_cli(a->fd, "  Cache media frames:          %s\n", ast_opt_cache_media_frames ? "Enabled" : "Disabled");

main/message.c

@@ -283,7 +283,7 @@ static int chan_msg_send_digit_end(struct ast_channel *chan, char digit,
  * This will not be registered as we never want anything to try
  * to create Message channels other than internally in this file.
  */
-static const struct ast_channel_tech msg_chan_tech_hack = {
+static struct ast_channel_tech msg_chan_tech_hack = {
 	.type             = "Message",
 	.description      = "Internal Text Message Processing",
 	.read             = chan_msg_read,
@@ -685,6 +685,10 @@ static struct ast_channel *create_msg_q_chan(void)
 		return NULL;
 	}
 
+	if (ast_opt_hide_messaging_ami_events) {
+		msg_chan_tech_hack.properties |= AST_CHAN_TP_INTERNAL;
+	}
+
 	ast_channel_tech_set(chan, &msg_chan_tech_hack);
 	ast_channel_unlock(chan);
 	ast_channel_unlink(chan);

main/options.c

@@ -457,6 +457,8 @@ void load_asterisk_conf(void)
 			}
 		} else if (!strcasecmp(v->name, "live_dangerously")) {
 			live_dangerously = ast_true(v->value);
+		} else if (!strcasecmp(v->name, "hide_messaging_ami_events")) {
+			ast_set2_flag(&ast_options, ast_true(v->value), AST_OPT_FLAG_HIDE_MESSAGING_AMI_EVENTS);
 		}
 	}
 	if (!ast_opt_remote) {