New universal CDR module

Asterisk Asterisk APIs
1

CDR module push data in realtime engines.
Is it good idea or not?

Example module code:

/*!
 * \file
 * \brief Custom Realtime CDR records.
 *
 * \author me
 *
 *
 * \arg See also \ref AstCDR
 *
 *
 * \ingroup cdr_drivers
 */

/*** MODULEINFO
	<depend></depend>
	<support_level>extended</support_level>
	<defaultenabled>no</defaultenabled>
 ***/

#include "asterisk.h"

#include "asterisk/paths.h"	/* use ast_config_AST_LOG_DIR */
#include "asterisk/channel.h"
#include "asterisk/cdr.h"
#include "asterisk/module.h"
#include "asterisk/config.h"
#include "asterisk/pbx.h"
#include "asterisk/utils.h"
#include "asterisk/cli.h"
#include "asterisk/app.h"

AST_MUTEX_DEFINE_STATIC(lock);

static const char config_file[] = "cdr_realtime.conf";

static const char desc[] = "Customizable Realtime CDR Backend";
static const char name[] = "cdr_realtime";

static char RT_Engine[80];
struct ast_variable *fields = NULL;

static void free_config(int reload);

static int load_config(int reload)
{
	struct ast_config *cfg;
	struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
	struct ast_variable *var, *first=NULL;

	if ((cfg = ast_config_load(config_file, config_flags)) == CONFIG_STATUS_FILEMISSING || cfg == CONFIG_STATUS_FILEINVALID) {
		ast_log(LOG_WARNING, "Failed to %sload configuration file. %s\n", reload ? "re" : "", reload ? "" : "Module not activated.");
		return -1;
	} else if (cfg == CONFIG_STATUS_FILEUNCHANGED) {
		return 0;
	}

	if (reload) {
		free_config(1);
	}

	// Load main params
	ast_copy_string(RT_Engine, ast_variable_retrieve(cfg, "general", "engine"), sizeof(RT_Engine));
	ast_verb(3, "CDR Realtime  [Engine] start CDR flow to engine %s\n",RT_Engine);
	
	if (var=ast_variable_browse(cfg, "columns")) {
		for (; var; var = var->next) {
			if(!fields){
				fields=ast_variable_new(var->name, var->value,"");
				first=fields;
			} else {
				first->next=ast_variable_new(var->name, var->value,"");
				first=first->next;
			}
			ast_verb(3, "CDR Realtime [add column] %s -> %s\n",var->name, var->value);
		}
	}
	
	ast_config_destroy(cfg);
	return 0;
}

static void free_config(int reload)
{
	if(fields){
		ast_variables_destroy(fields);
		fields=NULL;
	}
}

static int write_cdr(struct ast_cdr *cdr)
{
	struct ast_variable *var, *values=NULL, *first=NULL;
	struct ast_channel *dummy;
	char subst_buf[2048];
	//RAII_VAR(struct ast_variable *, fields, NULL, ast_variables_destroy);
	if(!fields){
		ast_verbose(1, "CDR Realtime - no fields for write in engine, skip CDR update");
		return 0;
	}
	ast_mutex_lock(&lock);
	dummy = ast_dummy_channel_alloc();
	if (!dummy) {
		ast_log(LOG_ERROR, "Unable to allocate channel for variable subsitution.\n");
		ast_mutex_unlock(&lock);
		return 0;
	}
	ast_channel_cdr_set(dummy, ast_cdr_dup(cdr));
	var=fields;
	for (; var; var = var->next) {
		pbx_substitute_variables_helper(dummy, var->value, subst_buf, sizeof(subst_buf) - 1);
		if(!values){
			values=ast_variable_new(var->name,subst_buf,"");
			first=values;
		} else {
			values->next=ast_variable_new(var->name,subst_buf,"");
			values=values->next;
		}
		ast_debug(3, "CDR Realtime [write] %s -> %s\n",var->name, subst_buf);
	}
	if(first){
		ast_store_realtime_fields(RT_Engine,first);
		ast_variables_destroy(first);
	}
	ast_channel_unref(dummy);
	ast_mutex_unlock(&lock);

	return 0;
}

static int unload_module(void)
{
	if (ast_cdr_unregister(name)) {
		return -1;
	} else {
		free_config(0);
		return 0;
	}
}

static int load_module(void)
{
	if (load_config(0)) {
		return AST_MODULE_LOAD_DECLINE;
	}

	if (ast_cdr_register(name, desc, write_cdr)) {
		ast_log(LOG_ERROR, "Unable to register custom Realtime CDR handling\n");
		free_config(0);
		return AST_MODULE_LOAD_DECLINE;
	}

	return AST_MODULE_LOAD_SUCCESS;
}

static int reload(void)
{
	int res = 0;

	ast_mutex_lock(&lock);
	res = load_config(1);
	ast_mutex_unlock(&lock);

	return res;
}

AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Realtime CDR Module",
	.support_level = AST_MODULE_SUPPORT_EXTENDED,
	.load = load_module,
	.unload = unload_module,
	.reload = reload,
	.load_pri = AST_MODPRI_CDR_DRIVER,
	.requires = "cdr",
);
2

I’am create github repo

3

It sounds interesting but my understanding is that realtime is for dynamic configuration and not so much historical logging. EDIT: I improved my understanding – queue_log can send output to realtime.

One testing issue you might run into under load is that CDR writes start blocking reads from the same realtime backend.

4

Yes, tested, backend speed mariadb - 50 query/sec. (2 CPU 1.4 GHz)

We have many phones, AVG CDR/realtime data query speed - about 10 query/sec.
For small installation (<1000 phones) its work fine. (eq remote office - filial)

My profit - failover for CDR data (CDR is important for us) and realtime insert in main office database.

extconfig.conf:

realtimeData => sqlite3, PhonesDB,MyPhones ; some info
CDR => mysql,MySqlServer1,CDR,1 ; DB in main office
CDR => sqlite3,CDRStorage,CDR,2 ; Local cache DB - resync by script in main office

ODBC (cdr_adaptive_odbc) work not good, maybe lost CDR data silent (no error in asterisk log), plus minimum module fo embeded installations

5

I like the cut of your jib!

Do you see differences now under load between what your new module stores and the other CDR backends store, for the same calls ?

6

Hi bulatov,

I wanted to write the same kind of module but storing cdr into kafka.
How is your module going? Is it working fine any flaws?

7

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.