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diff --git a/src/core/plugin.c b/src/core/plugin.c
index 3ba98df263cb7a3e257fbcac2a7dd364005ca979..b3f00bd655504075b97c5f158b8c45a8c0d20d05 100644 (file)
--- a/src/core/plugin.c
+++ b/src/core/plugin.c
} writer_t;
#define WRITER(obj) ((writer_t *)(obj))
+typedef struct {
+ callback_t super; /* cb_callback will always be NULL */
+#define r_user_data super.cb_user_data
+#define r_ctx super.cb_ctx
+ sdb_store_reader_t impl;
+} reader_t;
+#define READER(obj) ((reader_t *)(obj))
+
+typedef struct {
+ callback_t super; /* cb_callback will always be NULL */
+#define ts_user_data super.cb_user_data
+#define ts_ctx super.cb_ctx
+ sdb_timeseries_fetcher_t impl;
+} ts_fetcher_t;
+#define TS_FETCHER(obj) ((ts_fetcher_t *)(obj))
+
/*
* private variables
*/
static sdb_llist_t *cname_list = NULL;
static sdb_llist_t *shutdown_list = NULL;
static sdb_llist_t *log_list = NULL;
-static sdb_llist_t *ts_fetcher_list = NULL;
+static sdb_llist_t *timeseries_fetcher_list = NULL;
static sdb_llist_t *writer_list = NULL;
+static sdb_llist_t *reader_list = NULL;
static struct {
const char *type;
{ "cname", &cname_list },
{ "shutdown", &shutdown_list },
{ "log", &log_list },
- { "timeseries fetcher", &ts_fetcher_list },
+ { "timeseries fetcher", ×eries_fetcher_list },
{ "store writer", &writer_list },
+ { "store reader", &reader_list },
};
/*
assert(cb->cb_ctx);
- sdb_log(SDB_LOG_INFO, "core: Unregistering "
- "%s callback '%s' (module %s)", type, cb->super.name,
- cb->cb_ctx->info.plugin_name);
+ sdb_log(SDB_LOG_INFO, "Unregistering %s callback '%s' (module %s)",
+ type, cb->super.name, cb->cb_ctx->info.plugin_name);
sdb_object_deref(SDB_OBJ(cb));
}
}
/* else: other callbacks still reference it */
} /* plugin_unregister_by_name */
+/*
+ * store writer wrapper for performing database queries:
+ * It wraps another store writer, adding extra logic as needed.
+ */
+
+typedef struct {
+ sdb_object_t super;
+ sdb_store_writer_t *w;
+ sdb_object_t *ud;
+ sdb_query_opts_t opts;
+} query_writer_t;
+#define QUERY_WRITER_INIT(w, ud) { \
+ SDB_OBJECT_INIT, \
+ (w), (ud), \
+ SDB_DEFAULT_QUERY_OPTS \
+}
+#define QUERY_WRITER(obj) ((query_writer_t *)(obj))
+
+static int
+query_store_host(sdb_store_host_t *host, sdb_object_t *user_data)
+{
+ query_writer_t *qw = QUERY_WRITER(user_data);
+ return qw->w->store_host(host, qw->ud);
+} /* query_store_host */
+
+static int
+query_store_service(sdb_store_service_t *service, sdb_object_t *user_data)
+{
+ query_writer_t *qw = QUERY_WRITER(user_data);
+ return qw->w->store_service(service, qw->ud);
+} /* query_store_service */
+
+static int
+query_store_metric(sdb_store_metric_t *metric, sdb_object_t *user_data)
+{
+ query_writer_t *qw = QUERY_WRITER(user_data);
+ sdb_timeseries_info_t *infos[metric->stores_num];
+ sdb_metric_store_t stores[metric->stores_num];
+
+ const sdb_metric_store_t *orig_stores = metric->stores;
+ int status;
+ size_t i;
+
+ if (! qw->opts.describe_timeseries)
+ /* nothing further to do */
+ return qw->w->store_metric(metric, qw->ud);
+
+ for (i = 0; i < metric->stores_num; i++) {
+ sdb_metric_store_t *s = stores + i;
+ *s = metric->stores[i];
+ infos[i] = sdb_plugin_describe_timeseries(s->type, s->id);
+ s->info = infos[i];
+ }
+
+ metric->stores = stores;
+ status = qw->w->store_metric(metric, qw->ud);
+ metric->stores = orig_stores;
+
+ for (i = 0; i < metric->stores_num; i++)
+ sdb_timeseries_info_destroy(infos[i]);
+ return status;
+} /* query_store_metric */
+
+static int
+query_store_attribute(sdb_store_attribute_t *attr, sdb_object_t *user_data)
+{
+ query_writer_t *qw = QUERY_WRITER(user_data);
+ return qw->w->store_attribute(attr, qw->ud);
+} /* query_store_attribute */
+
+static sdb_store_writer_t query_writer = {
+ query_store_host, query_store_service,
+ query_store_metric, query_store_attribute,
+};
+
/*
* private types
*/
if (ctx->handle) {
const char *err;
- sdb_log(SDB_LOG_INFO, "core: Unloading module %s",
- ctx->info.plugin_name);
+ sdb_log(SDB_LOG_INFO, "Unloading module %s", ctx->info.plugin_name);
lt_dlerror();
lt_dlclose(ctx->handle);
if ((err = lt_dlerror()))
- sdb_log(SDB_LOG_WARNING, "core: Failed to unload module %s: %s",
+ sdb_log(SDB_LOG_WARNING, "Failed to unload module %s: %s",
ctx->info.plugin_name, err);
}
return ctx;
} /* ctx_create */
-static int
-plugin_cb_init(sdb_object_t *obj, va_list ap)
+/*
+ * plugin_init_ok:
+ * Checks whether the registration of a new plugin identified by 'obj' is
+ * okay. It consumes the first two arguments of 'ap'.
+ */
+static bool
+plugin_init_ok(sdb_object_t *obj, va_list ap)
{
sdb_llist_t **list = va_arg(ap, sdb_llist_t **);
- const char *type = va_arg(ap, const char *);
- void *callback = va_arg(ap, void *);
- sdb_object_t *ud = va_arg(ap, sdb_object_t *);
+ const char *type = va_arg(ap, const char *);
- assert(list);
- assert(type);
- assert(obj);
+ assert(list); assert(type);
if (sdb_llist_search_by_name(*list, obj->name)) {
- sdb_log(SDB_LOG_WARNING, "core: %s callback '%s' "
- "has already been registered. Ignoring newly "
- "registered version.", type, obj->name);
- return -1;
+ sdb_log(SDB_LOG_WARNING, "%s callback '%s' has already been "
+ "registered. Ignoring newly registered version.",
+ type, obj->name);
+ return 0;
}
+ return 1;
+} /* plugin_init_ok */
+
+static int
+plugin_cb_init(sdb_object_t *obj, va_list ap)
+{
+ void *callback;
+ sdb_object_t *ud;
+
+ if (! plugin_init_ok(obj, ap))
+ return -1;
+
+ callback = va_arg(ap, void *);
+ ud = va_arg(ap, sdb_object_t *);
/* cb_ctx may be NULL if the plugin was not registered by a plugin */
static int
plugin_writer_init(sdb_object_t *obj, va_list ap)
{
- sdb_store_writer_t *impl = va_arg(ap, sdb_store_writer_t *);
- sdb_object_t *ud = va_arg(ap, sdb_object_t *);
+ sdb_store_writer_t *impl;
+ sdb_object_t *ud;
+ if (! plugin_init_ok(obj, ap))
+ return -1;
+
+ impl = va_arg(ap, sdb_store_writer_t *);
+ ud = va_arg(ap, sdb_object_t *);
assert(impl);
if ((! impl->store_host) || (! impl->store_service)
- || (! impl->store_metric) || (! impl->store_attribute)
- || (! impl->store_service_attr) || (! impl->store_metric_attr)) {
- sdb_log(SDB_LOG_ERR, "core: store writer callback '%s' "
- "does not fully implement the writer interface.",
- obj->name);
- return -1;
- }
- if (sdb_llist_search_by_name(writer_list, obj->name)) {
- sdb_log(SDB_LOG_WARNING, "core: store writer callback '%s' "
- "has already been registered. Ignoring newly "
- "registered version.", obj->name);
+ || (! impl->store_metric) || (! impl->store_attribute)) {
+ sdb_log(SDB_LOG_ERR, "store writer callback '%s' does not fully "
+ "implement the writer interface.", obj->name);
return -1;
}
plugin_writer_destroy
};
+static int
+plugin_reader_init(sdb_object_t *obj, va_list ap)
+{
+ sdb_store_reader_t *impl;
+ sdb_object_t *ud;
+
+ if (! plugin_init_ok(obj, ap))
+ return -1;
+
+ impl = va_arg(ap, sdb_store_reader_t *);
+ ud = va_arg(ap, sdb_object_t *);
+ assert(impl);
+
+ if ((! impl->prepare_query) || (! impl->execute_query)) {
+ sdb_log(SDB_LOG_ERR, "store reader callback '%s' does not fully "
+ "implement the reader interface.", obj->name);
+ return -1;
+ }
+
+ /* ctx may be NULL if the callback was not registered by a plugin */
+
+ READER(obj)->impl = *impl;
+ READER(obj)->r_ctx = ctx_get();
+ sdb_object_ref(SDB_OBJ(READER(obj)->r_ctx));
+
+ sdb_object_ref(ud);
+ READER(obj)->r_user_data = ud;
+ return 0;
+} /* plugin_reader_init */
+
+static void
+plugin_reader_destroy(sdb_object_t *obj)
+{
+ assert(obj);
+ sdb_object_deref(READER(obj)->r_user_data);
+ sdb_object_deref(SDB_OBJ(READER(obj)->r_ctx));
+} /* plugin_reader_destroy */
+
+static sdb_type_t reader_type = {
+ sizeof(reader_t),
+
+ plugin_reader_init,
+ plugin_reader_destroy
+};
+
+static int
+plugin_ts_fetcher_init(sdb_object_t *obj, va_list ap)
+{
+ sdb_timeseries_fetcher_t *impl;
+ sdb_object_t *ud;
+
+ if (! plugin_init_ok(obj, ap))
+ return -1;
+
+ impl = va_arg(ap, sdb_timeseries_fetcher_t *);
+ ud = va_arg(ap, sdb_object_t *);
+ assert(impl);
+
+ if ((! impl->describe) || (! impl->fetch)) {
+ sdb_log(SDB_LOG_ERR, "timeseries fetcher callback '%s' does not fully "
+ "implement the interface.", obj->name);
+ return -1;
+ }
+
+ /* ctx may be NULL if the callback was not registered by a plugin */
+
+ TS_FETCHER(obj)->impl = *impl;
+ TS_FETCHER(obj)->ts_ctx = ctx_get();
+ sdb_object_ref(SDB_OBJ(TS_FETCHER(obj)->ts_ctx));
+
+ sdb_object_ref(ud);
+ TS_FETCHER(obj)->ts_user_data = ud;
+ return 0;
+} /* plugin_ts_fetcher_init */
+
+static void
+plugin_ts_fetcher_destroy(sdb_object_t *obj)
+{
+ assert(obj);
+ sdb_object_deref(TS_FETCHER(obj)->ts_user_data);
+ sdb_object_deref(SDB_OBJ(TS_FETCHER(obj)->ts_ctx));
+} /* plugin_ts_fetcher_destroy */
+
+static sdb_type_t ts_fetcher_type = {
+ sizeof(ts_fetcher_t),
+
+ plugin_ts_fetcher_init,
+ plugin_ts_fetcher_destroy
+};
+
static int
module_init(const char *name, lt_dlhandle lh, sdb_plugin_info_t *info)
{
mod_init = (int (*)(sdb_plugin_info_t *))lt_dlsym(lh, "sdb_module_init");
if (! mod_init) {
- sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
+ sdb_log(SDB_LOG_ERR, "Failed to load plugin '%s': "
"could not find symbol 'sdb_module_init'", name);
return -1;
}
status = mod_init(info);
if (status) {
- sdb_log(SDB_LOG_ERR, "core: Failed to initialize "
- "module '%s'", name);
+ sdb_log(SDB_LOG_ERR, "Failed to initialize module '%s'", name);
plugin_unregister_by_name(name);
return -1;
}
if (access(filename, R_OK)) {
char errbuf[1024];
- sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s' (%s): %s",
+ sdb_log(SDB_LOG_ERR, "Failed to load plugin '%s' (%s): %s",
name, filename, sdb_strerror(errno, errbuf, sizeof(errbuf)));
return -1;
}
lh = lt_dlopen(filename);
if (! lh) {
- sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': %s"
+ sdb_log(SDB_LOG_ERR, "Failed to load plugin '%s': %s"
"The most common cause for this problem are missing "
"dependencies.\n", name, lt_dlerror());
return -1;
}
if (ctx_get())
- sdb_log(SDB_LOG_WARNING, "core: Discarding old plugin context");
+ sdb_log(SDB_LOG_WARNING, "Discarding old plugin context");
ctx = ctx_create(name);
if (! ctx) {
- sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin context");
+ sdb_log(SDB_LOG_ERR, "Failed to initialize plugin context");
return -1;
}
if ((status = module_init(name, lh, &ctx->info))) {
sdb_object_deref(SDB_OBJ(ctx));
+ ctx_set(NULL);
return status;
}
/* compare minor version */
if ((ctx->info.version < 0)
|| ((int)(ctx->info.version / 100) != (int)(SDB_VERSION / 100)))
- sdb_log(SDB_LOG_WARNING, "core: WARNING: version of "
- "plugin '%s' (%i.%i.%i) does not match our version "
- "(%i.%i.%i); this might cause problems",
- name, SDB_VERSION_DECODE(ctx->info.version),
+ sdb_log(SDB_LOG_WARNING, "WARNING: plugin version (%i.%i.%i) "
+ "does not match core version (%i.%i.%i); "
+ "this might cause problems",
+ SDB_VERSION_DECODE(ctx->info.version),
SDB_VERSION_DECODE(SDB_VERSION));
sdb_llist_append(all_plugins, SDB_OBJ(ctx));
- sdb_log(SDB_LOG_INFO, "core: Successfully loaded "
- "plugin %s v%i (%s)", ctx->info.plugin_name,
- ctx->info.plugin_version,
+ /* log messages will be prefixed by the plugin name */
+ sdb_log(SDB_LOG_INFO, "Successfully loaded "
+ "version %i (%s)", ctx->info.plugin_version,
INFO_GET(&ctx->info, description));
- sdb_log(SDB_LOG_INFO, "core: Plugin %s: %s, License: %s",
- ctx->info.plugin_name,
+ sdb_log(SDB_LOG_INFO, "%s, License: %s",
INFO_GET(&ctx->info, copyright),
INFO_GET(&ctx->info, license));
} /* plugin_get_name */
static int
-plugin_add_callback(sdb_llist_t **list, const char *type,
- const char *name, void *callback, sdb_object_t *user_data)
+plugin_add_impl(sdb_llist_t **list, sdb_type_t T, const char *type,
+ const char *name, void *impl, sdb_object_t *user_data)
{
sdb_object_t *obj;
- if ((! name) || (! callback))
+ if ((! name) || (! impl))
return -1;
assert(list);
if (! *list)
return -1;
- obj = sdb_object_create(name, callback_type,
- list, type, callback, user_data);
+ obj = sdb_object_create(name, T, list, type, impl, user_data);
if (! obj)
return -1;
/* pass control to the list */
sdb_object_deref(obj);
- sdb_log(SDB_LOG_INFO, "core: Registered %s callback '%s'.",
- type, name);
+ sdb_log(SDB_LOG_INFO, "Registered %s callback '%s'.", type, name);
return 0;
-} /* plugin_add_callback */
+} /* plugin_add_impl */
+
+/*
+ * object meta-data
+ */
+
+typedef struct {
+ int obj_type;
+ sdb_time_t last_update;
+ sdb_time_t interval;
+} interval_fetcher_t;
+
+static int
+interval_fetcher_host(sdb_store_host_t *host, sdb_object_t *user_data)
+{
+ interval_fetcher_t *lu = SDB_OBJ_WRAPPER(user_data)->data;
+ lu->obj_type = SDB_HOST;
+ lu->last_update = host->last_update;
+ return 0;
+} /* interval_fetcher_host */
+
+static int
+interval_fetcher_service(sdb_store_service_t *svc, sdb_object_t *user_data)
+{
+ interval_fetcher_t *lu = SDB_OBJ_WRAPPER(user_data)->data;
+ lu->obj_type = SDB_SERVICE;
+ lu->last_update = svc->last_update;
+ return 0;
+} /* interval_fetcher_service */
+
+static int
+interval_fetcher_metric(sdb_store_metric_t *metric, sdb_object_t *user_data)
+{
+ interval_fetcher_t *lu = SDB_OBJ_WRAPPER(user_data)->data;
+ lu->obj_type = SDB_METRIC;
+ lu->last_update = metric->last_update;
+ return 0;
+} /* interval_fetcher_metric */
+
+static int
+interval_fetcher_attr(sdb_store_attribute_t *attr, sdb_object_t *user_data)
+{
+ interval_fetcher_t *lu = SDB_OBJ_WRAPPER(user_data)->data;
+ lu->obj_type = SDB_ATTRIBUTE;
+ lu->last_update = attr->last_update;
+ return 0;
+} /* interval_fetcher_attr */
+
+static sdb_store_writer_t interval_fetcher = {
+ interval_fetcher_host, interval_fetcher_service,
+ interval_fetcher_metric, interval_fetcher_attr,
+};
+
+static int
+get_interval(int obj_type, const char *hostname,
+ int parent_type, const char *parent, const char *name,
+ sdb_time_t last_update, sdb_time_t *interval_out)
+{
+ sdb_ast_fetch_t fetch = SDB_AST_FETCH_INIT;
+ char hn[hostname ? strlen(hostname) + 1 : 1];
+ char pn[parent ? strlen(parent) + 1 : 1];
+ char n[strlen(name) + 1];
+ int status;
+
+ interval_fetcher_t lu = { 0, 0, 0 };
+ sdb_object_wrapper_t obj = SDB_OBJECT_WRAPPER_STATIC(&lu);
+ sdb_time_t interval;
+
+ assert(name);
+
+ if (hostname)
+ strncpy(hn, hostname, sizeof(hn));
+ if (parent)
+ strncpy(pn, parent, sizeof(pn));
+ strncpy(n, name, sizeof(n));
+
+ fetch.obj_type = obj_type;
+ fetch.hostname = hostname ? hn : NULL;
+ fetch.parent_type = parent_type;
+ fetch.parent = parent ? pn : NULL;
+ fetch.name = n;
+
+ status = sdb_plugin_query(SDB_AST_NODE(&fetch),
+ &interval_fetcher, SDB_OBJ(&obj), NULL, NULL);
+ if ((status < 0) || (lu.obj_type != obj_type) || (lu.last_update == 0)) {
+ *interval_out = 0;
+ return 0;
+ }
+
+ if (lu.last_update >= last_update) {
+ if (lu.last_update > last_update)
+ sdb_log(SDB_LOG_DEBUG, "Cannot update %s '%s' - "
+ "value too old (%"PRIsdbTIME" < %"PRIsdbTIME")",
+ SDB_STORE_TYPE_TO_NAME(obj_type), name,
+ lu.last_update, last_update);
+ *interval_out = lu.interval;
+ return 1;
+ }
+
+ interval = last_update - lu.last_update;
+ if (lu.interval && interval)
+ interval = (sdb_time_t)((0.9 * (double)lu.interval)
+ + (0.1 * (double)interval));
+ *interval_out = interval;
+ return 0;
+} /* get_interval */
+
+static void
+get_backend(char **backends, size_t *backends_num)
+{
+ const sdb_plugin_info_t *info;
+
+ info = sdb_plugin_current();
+ if ((! info) || (! info->plugin_name) || (! *info->plugin_name)) {
+ *backends_num = 0;
+ return;
+ }
+
+ backends[0] = info->plugin_name;
+ *backends_num = 1;
+} /* get_backend */
/*
* public API
if (! all_plugins) {
if (! (all_plugins = sdb_llist_create())) {
- sdb_log(SDB_LOG_ERR, "core: Failed to load plugin '%s': "
+ sdb_log(SDB_LOG_ERR, "Failed to load plugin '%s': "
"internal error while creating linked list", name);
return -1;
}
ctx_t *old_ctx = ctx_set(ctx);
status = module_init(ctx->info.plugin_name, ctx->handle, NULL);
+ ctx_set(old_ctx);
if (status)
return status;
- sdb_log(SDB_LOG_INFO, "core: Successfully reloaded plugin "
+ ctx_set(old_ctx);
+ sdb_log(SDB_LOG_INFO, "Successfully reloaded plugin "
"'%s' (%s)", ctx->info.plugin_name,
INFO_GET(&ctx->info, description));
- ctx_set(old_ctx);
}
++ctx->use_cnt;
return 0;
ctx_t *ctx = ctx_get();
if (! ctx) {
- sdb_log(SDB_LOG_ERR, "core: Invalid attempt to register a "
+ sdb_log(SDB_LOG_ERR, "Invalid attempt to register a "
"config callback from outside a plugin");
return -1;
}
- return plugin_add_callback(&config_list, "config", ctx->info.plugin_name,
- (void *)callback, NULL);
+ return plugin_add_impl(&config_list, callback_type, "config",
+ ctx->info.plugin_name, (void *)callback, NULL);
} /* sdb_plugin_register_config */
int
sdb_object_t *user_data)
{
char cb_name[1024];
- return plugin_add_callback(&init_list, "init",
+ return plugin_add_impl(&init_list, callback_type, "init",
plugin_get_name(name, cb_name, sizeof(cb_name)),
(void *)callback, user_data);
} /* sdb_plugin_register_init */
@@ -739,7 +1050,7 @@ sdb_plugin_register_shutdown(const char *name, sdb_plugin_shutdown_cb callback,
sdb_object_t *user_data)
{
char cb_name[1024];
- return plugin_add_callback(&shutdown_list, "shutdown",
+ return plugin_add_impl(&shutdown_list, callback_type, "shutdown",
plugin_get_name(name, cb_name, sizeof(cb_name)),
(void *)callback, user_data);
} /* sdb_plugin_register_shutdown */
sdb_object_t *user_data)
{
char cb_name[1024];
- return plugin_add_callback(&log_list, "log",
+ return plugin_add_impl(&log_list, callback_type, "log",
plugin_get_name(name, cb_name, sizeof(cb_name)),
callback, user_data);
} /* sdb_plugin_register_log */
sdb_object_t *user_data)
{
char cb_name[1024];
- return plugin_add_callback(&cname_list, "cname",
+ return plugin_add_impl(&cname_list, callback_type, "cname",
plugin_get_name(name, cb_name, sizeof(cb_name)),
callback, user_data);
} /* sdb_plugin_register_cname */
@@ -792,9 +1103,8 @@ sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback
ctx_t *ctx = ctx_get();
if (! ctx) {
- sdb_log(SDB_LOG_ERR, "core: Cannot determine interval "
- "for collector %s; none specified and no plugin "
- "context found", cb_name);
+ sdb_log(SDB_LOG_ERR, "Cannot determine interval for collector %s; "
+ "none specified and no plugin context found", cb_name);
return -1;
}
@@ -803,8 +1113,8 @@ sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback
if (! (CCB(obj)->ccb_next_update = sdb_gettime())) {
char errbuf[1024];
- sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
- "time: %s", sdb_strerror(errno, errbuf, sizeof(errbuf)));
+ sdb_log(SDB_LOG_ERR, "Failed to determine current time: %s",
+ sdb_strerror(errno, errbuf, sizeof(errbuf)));
sdb_object_deref(obj);
return -1;
}
@@ -818,55 +1128,40 @@ sdb_plugin_register_collector(const char *name, sdb_plugin_collector_cb callback
/* pass control to the list */
sdb_object_deref(obj);
- sdb_log(SDB_LOG_INFO, "core: Registered collector callback '%s' "
+ sdb_log(SDB_LOG_INFO, "Registered collector callback '%s' "
"(interval = %.3fs).", cb_name,
SDB_TIME_TO_DOUBLE(CCB(obj)->ccb_interval));
return 0;
} /* sdb_plugin_register_collector */
int
-sdb_plugin_register_ts_fetcher(const char *name,
- sdb_plugin_fetch_ts_cb callback, sdb_object_t *user_data)
+sdb_plugin_register_timeseries_fetcher(const char *name,
+ sdb_timeseries_fetcher_t *fetcher, sdb_object_t *user_data)
{
- return plugin_add_callback(&ts_fetcher_list, "time-series fetcher",
- name, callback, user_data);
-} /* sdb_plugin_register_ts_fetcher */
+ return plugin_add_impl(×eries_fetcher_list, ts_fetcher_type, "time-series fetcher",
+ name, fetcher, user_data);
+} /* sdb_plugin_register_timeseries_fetcher */
int
sdb_plugin_register_writer(const char *name,
sdb_store_writer_t *writer, sdb_object_t *user_data)
{
char cb_name[1024];
- sdb_object_t *obj;
-
- if ((! name) || (! writer))
- return -1;
-
- if (! writer_list)
- writer_list = sdb_llist_create();
- if (! writer_list)
- return -1;
-
- plugin_get_name(name, cb_name, sizeof(cb_name));
-
- obj = sdb_object_create(cb_name, writer_type,
+ return plugin_add_impl(&writer_list, writer_type, "store writer",
+ plugin_get_name(name, cb_name, sizeof(cb_name)),
writer, user_data);
- if (! obj)
- return -1;
-
- if (sdb_llist_append(writer_list, obj)) {
- sdb_object_deref(obj);
- return -1;
- }
-
- /* pass control to the list */
- sdb_object_deref(obj);
-
- sdb_log(SDB_LOG_INFO, "core: Registered store writer callback '%s'.",
- cb_name);
- return 0;
} /* sdb_store_register_writer */
+int
+sdb_plugin_register_reader(const char *name,
+ sdb_store_reader_t *reader, sdb_object_t *user_data)
+{
+ char cb_name[1024];
+ return plugin_add_impl(&reader_list, reader_type, "store reader",
+ plugin_get_name(name, cb_name, sizeof(cb_name)),
+ reader, user_data);
+} /* sdb_plugin_register_reader */
+
void
sdb_plugin_unregister_all(void)
{
continue;
sdb_llist_clear(list);
- sdb_log(SDB_LOG_INFO, "core: Unregistered %zu %s callback%s",
+ sdb_log(SDB_LOG_INFO, "Unregistered %zu %s callback%s",
len, type, len == 1 ? "" : "s");
}
} /* sdb_plugin_unregister_all */
c = ctx_get();
if (! c) {
- sdb_plugin_log(SDB_LOG_ERR, "core: Invalid read access to plugin "
+ sdb_log(SDB_LOG_ERR, "Invalid read access to plugin "
"context outside a plugin");
return plugin_default_ctx;
}
c = ctx_get();
if (! c) {
- sdb_plugin_log(SDB_LOG_ERR, "core: Invalid write access to plugin "
+ sdb_log(SDB_LOG_ERR, "Invalid write access to plugin "
"context outside a plugin");
return -1;
}
if (! plugin) {
ctx_t *ctx = CTX(sdb_llist_search_by_name(all_plugins, name));
if (! ctx)
- sdb_log(SDB_LOG_ERR, "core: Cannot configure unknown "
- "plugin '%s'. Missing 'LoadPlugin \"%s\"'?",
+ sdb_log(SDB_LOG_ERR, "Cannot configure unknown plugin '%s'. "
+ "Missing 'LoadPlugin \"%s\"'?",
name, name);
else
- sdb_log(SDB_LOG_ERR, "core: Plugin '%s' did not register "
+ sdb_log(SDB_LOG_ERR, "Plugin '%s' did not register "
"a config callback.", name);
errno = ENOENT;
return -1;
if (ctx->use_cnt)
continue;
- sdb_log(SDB_LOG_INFO, "core: Module %s no longer in use",
+ sdb_log(SDB_LOG_INFO, "Module %s no longer in use",
ctx->info.plugin_name);
sdb_llist_iter_remove_current(iter);
plugin_unregister_by_name(ctx->info.plugin_name);
old_ctx = ctx_set(cb->cb_ctx);
if (callback(cb->cb_user_data)) {
- sdb_log(SDB_LOG_ERR, "core: Failed to initialize plugin "
- "'%s'. Unregistering all callbacks.", obj->name);
+ sdb_log(SDB_LOG_ERR, "Failed to initialize plugin '%s'. "
+ "Unregistering all callbacks.", obj->name);
ctx_set(old_ctx);
plugin_unregister_by_name(cb->cb_ctx->info.plugin_name);
++ret;
old_ctx = ctx_set(cb->cb_ctx);
if (callback(cb->cb_user_data)) {
- sdb_log(SDB_LOG_ERR, "core: Failed to shutdown plugin '%s'.",
+ sdb_log(SDB_LOG_ERR, "Failed to shutdown plugin '%s'.",
obj->name);
++ret;
}
sdb_plugin_collector_loop(sdb_plugin_loop_t *loop)
{
if (! collector_list) {
- sdb_log(SDB_LOG_WARNING, "core: No collectors registered. "
+ sdb_log(SDB_LOG_WARNING, "No collectors registered. "
"Quiting main loop.");
return -1;
}
if (! (now = sdb_gettime())) {
char errbuf[1024];
- sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
+ sdb_log(SDB_LOG_ERR, "Failed to determine current "
"time in collector main loop: %s",
sdb_strerror(errno, errbuf, sizeof(errbuf)));
now = CCB(obj)->ccb_next_update;
while (loop->do_loop && sdb_sleep(interval, &interval)) {
if (errno != EINTR) {
char errbuf[1024];
- sdb_log(SDB_LOG_ERR, "core: Failed to sleep "
+ sdb_log(SDB_LOG_ERR, "Failed to sleep "
"in collector main loop: %s",
sdb_strerror(errno, errbuf, sizeof(errbuf)));
sdb_llist_insert_sorted(collector_list, obj,
if (! interval)
interval = loop->default_interval;
if (! interval) {
- sdb_log(SDB_LOG_WARNING, "core: No interval configured "
+ sdb_log(SDB_LOG_WARNING, "No interval configured "
"for plugin '%s'; skipping any further "
"iterations.", obj->name);
sdb_object_deref(obj);
if (! (now = sdb_gettime())) {
char errbuf[1024];
- sdb_log(SDB_LOG_ERR, "core: Failed to determine current "
+ sdb_log(SDB_LOG_ERR, "Failed to determine current "
"time in collector main loop: %s",
sdb_strerror(errno, errbuf, sizeof(errbuf)));
now = CCB(obj)->ccb_next_update;
}
if (now > CCB(obj)->ccb_next_update) {
- sdb_log(SDB_LOG_WARNING, "core: Plugin '%s' took too "
+ sdb_log(SDB_LOG_WARNING, "Plugin '%s' took too "
"long; skipping iterations to keep up.",
obj->name);
CCB(obj)->ccb_next_update = now;
if (sdb_llist_insert_sorted(collector_list, obj,
plugin_cmp_next_update)) {
- sdb_log(SDB_LOG_ERR, "core: Failed to re-insert "
- "plugin '%s' into collector list. Unable to further "
- "use the plugin.",
+ sdb_log(SDB_LOG_ERR, "Failed to re-insert plugin '%s' into "
+ "collector list. Unable to further use the plugin.",
obj->name);
sdb_object_deref(obj);
return -1;
int
sdb_plugin_log(int prio, const char *msg)
{
- sdb_llist_iter_t *iter;
+ const sdb_plugin_info_t *info;
int ret = -1;
- bool logged = 0;
-
if (! msg)
return 0;
- iter = sdb_llist_get_iter(log_list);
- while (sdb_llist_iter_has_next(iter)) {
- sdb_plugin_log_cb callback;
- int tmp;
+ info = sdb_plugin_current();
- sdb_object_t *obj = sdb_llist_iter_get_next(iter);
- assert(obj);
+ {
+ const char *plugin_name = info ? info->plugin_name : "";
+ char log_msg[strlen(msg) + strlen(plugin_name) + strlen(" plugin: ") + 1];
- callback = (sdb_plugin_log_cb)CB(obj)->cb_callback;
- tmp = callback(prio, msg, CB(obj)->cb_user_data);
- if (tmp > ret)
- ret = tmp;
+ sdb_llist_iter_t *iter;
+ bool logged = 0;
- if (CB(obj)->cb_ctx)
- logged = 1;
- /* else: this is an internally registered callback */
- }
- sdb_llist_iter_destroy(iter);
+ if (*plugin_name)
+ snprintf(log_msg, sizeof(log_msg), "%s plugin: %s",
+ plugin_name, msg);
+ else
+ strncpy(log_msg, msg, sizeof(log_msg));
- if (! logged)
- return fprintf(stderr, "[%s] %s\n", SDB_LOG_PRIO_TO_STRING(prio), msg);
+ iter = sdb_llist_get_iter(log_list);
+ while (sdb_llist_iter_has_next(iter)) {
+ sdb_plugin_log_cb callback;
+ int tmp;
+
+ sdb_object_t *obj = sdb_llist_iter_get_next(iter);
+ assert(obj);
+
+ callback = (sdb_plugin_log_cb)CB(obj)->cb_callback;
+ tmp = callback(prio, msg, CB(obj)->cb_user_data);
+ if (tmp > ret)
+ ret = tmp;
+
+ if (CB(obj)->cb_ctx)
+ logged = 1;
+ /* else: this is an internally registered callback */
+ }
+ sdb_llist_iter_destroy(iter);
+
+ if (! logged)
+ return fprintf(stderr, "[%s] %s\n",
+ SDB_LOG_PRIO_TO_STRING(prio), log_msg);
+ }
return ret;
} /* sdb_plugin_log */
sdb_plugin_fetch_timeseries(const char *type, const char *id,
sdb_timeseries_opts_t *opts)
{
- callback_t *plugin;
- sdb_plugin_fetch_ts_cb callback;
+ ts_fetcher_t *fetcher;
sdb_timeseries_t *ts;
ctx_t *old_ctx;
if ((! type) || (! id) || (! opts))
return NULL;
- plugin = CB(sdb_llist_search_by_name(ts_fetcher_list, type));
- if (! plugin) {
- sdb_log(SDB_LOG_ERR, "core: Cannot fetch time-series of type %s: "
+ fetcher = TS_FETCHER(sdb_llist_search_by_name(timeseries_fetcher_list, type));
+ if (! fetcher) {
+ sdb_log(SDB_LOG_ERR, "Cannot fetch time-series of type %s: "
"no such plugin loaded", type);
errno = ENOENT;
return NULL;
}
- old_ctx = ctx_set(plugin->cb_ctx);
- callback = (sdb_plugin_fetch_ts_cb)plugin->cb_callback;
- ts = callback(id, opts, plugin->cb_user_data);
+ old_ctx = ctx_set(fetcher->ts_ctx);
+ ts = fetcher->impl.fetch(id, opts, fetcher->ts_user_data);
ctx_set(old_ctx);
return ts;
} /* sdb_plugin_fetch_timeseries */
+sdb_timeseries_info_t *
+sdb_plugin_describe_timeseries(const char *type, const char *id)
+{
+ ts_fetcher_t *fetcher;
+ sdb_timeseries_info_t *ts_info;
+
+ ctx_t *old_ctx;
+
+ if ((! type) || (! id))
+ return NULL;
+
+ fetcher = TS_FETCHER(sdb_llist_search_by_name(timeseries_fetcher_list, type));
+ if (! fetcher) {
+ sdb_log(SDB_LOG_ERR, "Cannot describe time-series of type %s: "
+ "no such plugin loaded", type);
+ errno = ENOENT;
+ return NULL;
+ }
+
+ old_ctx = ctx_set(fetcher->ts_ctx);
+ ts_info = fetcher->impl.describe(id, fetcher->ts_user_data);
+ ctx_set(old_ctx);
+ return ts_info;
+} /* sdb_plugin_describe_timeseries */
+
+int
+sdb_plugin_query(sdb_ast_node_t *ast,
+ sdb_store_writer_t *w, sdb_object_t *wd,
+ sdb_query_opts_t *opts, sdb_strbuf_t *errbuf)
+{
+ query_writer_t qw = QUERY_WRITER_INIT(w, wd);
+ reader_t *reader;
+ sdb_object_t *q;
+
+ size_t n = sdb_llist_len(reader_list);
+ int status = 0;
+
+ if (! ast)
+ return 0;
+
+ if (opts)
+ qw.opts = *opts;
+
+ if ((ast->type != SDB_AST_TYPE_FETCH)
+ && (ast->type != SDB_AST_TYPE_LIST)
+ && (ast->type != SDB_AST_TYPE_LOOKUP)) {
+ sdb_log(SDB_LOG_ERR, "Cannot execute query of type %s",
+ SDB_AST_TYPE_TO_STRING(ast));
+ sdb_strbuf_sprintf(errbuf, "Cannot execute query of type %s",
+ SDB_AST_TYPE_TO_STRING(ast));
+ return -1;
+ }
+
+ if (n != 1) {
+ char *msg = (n > 0)
+ ? "Cannot execute query: multiple readers not supported"
+ : "Cannot execute query: no readers registered";
+ sdb_strbuf_sprintf(errbuf, "%s", msg);
+ sdb_log(SDB_LOG_ERR, "%s", msg);
+ return -1;
+ }
+
+ reader = READER(sdb_llist_get(reader_list, 0));
+ assert(reader);
+
+ q = reader->impl.prepare_query(ast, errbuf, reader->r_user_data);
+ if (q)
+ status = reader->impl.execute_query(q, &query_writer, SDB_OBJ(&qw),
+ errbuf, reader->r_user_data);
+ else
+ status = -1;
+
+ sdb_object_deref(SDB_OBJ(q));
+ sdb_object_deref(SDB_OBJ(reader));
+ return status;
+} /* sdb_plugin_query */
+
int
sdb_plugin_store_host(const char *name, sdb_time_t last_update)
{
+ sdb_store_host_t host = SDB_STORE_HOST_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
int status = 0;
if (! name)
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store host: no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(name));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
+ host.name = cname;
+ host.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_HOST, NULL, -1, NULL, cname,
+ host.last_update, &host.interval)) {
+ free(cname);
+ return 1;
+ }
+ host.backends = (const char * const *)backends;
+ get_backend(backends, &host.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_host(name, last_update, writer->w_user_data);
+ s = writer->impl.store_host(&host, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+ free(cname);
return status;
} /* sdb_plugin_store_host */
sdb_plugin_store_service(const char *hostname, const char *name,
sdb_time_t last_update)
{
+ sdb_store_service_t service = SDB_STORE_SERVICE_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
+ sdb_data_t d;
+
int status = 0;
if ((! hostname) || (! name))
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store service: "
+ "no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(hostname));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
+ service.hostname = cname;
+ service.name = name;
+ service.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_SERVICE, cname, -1, NULL, name,
+ service.last_update, &service.interval)) {
+ free(cname);
+ return 1;
+ }
+ service.backends = (const char * const *)backends;
+ get_backend(backends, &service.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_service(hostname, name, last_update,
- writer->w_user_data);
+ s = writer->impl.store_service(&service, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+
+ if (! status) {
+ /* record the hostname as an attribute */
+ d.type = SDB_TYPE_STRING;
+ d.data.string = cname;
+ if (sdb_plugin_store_service_attribute(cname, name,
+ "hostname", &d, service.last_update))
+ status = -1;
+ }
+
+ free(cname);
return status;
} /* sdb_plugin_store_service */
sdb_plugin_store_metric(const char *hostname, const char *name,
sdb_metric_store_t *store, sdb_time_t last_update)
{
+ sdb_store_metric_t metric = SDB_STORE_METRIC_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
+ sdb_data_t d;
+
int status = 0;
if ((! hostname) || (! name))
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store metric: no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(hostname));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
if (store && ((! store->type) || (! store->id)))
store = NULL;
+ metric.hostname = cname;
+ metric.name = name;
+ if (store) {
+ if (store->last_update < last_update)
+ store->last_update = last_update;
+ metric.stores = store;
+ metric.stores_num = 1;
+ }
+ metric.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_METRIC, cname, -1, NULL, name,
+ metric.last_update, &metric.interval)) {
+ free(cname);
+ return 1;
+ }
+ metric.backends = (const char * const *)backends;
+ get_backend(backends, &metric.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_metric(hostname, name, store, last_update,
- writer->w_user_data);
+ s = writer->impl.store_metric(&metric, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+
+ if (! status) {
+ /* record the hostname as an attribute */
+ d.type = SDB_TYPE_STRING;
+ d.data.string = cname;
+ if (sdb_plugin_store_metric_attribute(cname, name,
+ "hostname", &d, metric.last_update))
+ status = -1;
+ }
+
+ free(cname);
return status;
} /* sdb_plugin_store_metric */
sdb_plugin_store_attribute(const char *hostname, const char *key,
const sdb_data_t *value, sdb_time_t last_update)
{
+ sdb_store_attribute_t attr = SDB_STORE_ATTRIBUTE_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
int status = 0;
if ((! hostname) || (! key) || (! value))
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store attribute: no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(hostname));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
+ attr.parent_type = SDB_HOST;
+ attr.parent = cname;
+ attr.key = key;
+ attr.value = *value;
+ attr.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_ATTRIBUTE, cname, -1, NULL, key,
+ attr.last_update, &attr.interval)) {
+ free(cname);
+ return 1;
+ }
+ attr.backends = (const char * const *)backends;
+ get_backend(backends, &attr.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_attribute(hostname, key, value, last_update,
- writer->w_user_data);
+ s = writer->impl.store_attribute(&attr, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+ free(cname);
return status;
} /* sdb_plugin_store_attribute */
sdb_plugin_store_service_attribute(const char *hostname, const char *service,
const char *key, const sdb_data_t *value, sdb_time_t last_update)
{
+ sdb_store_attribute_t attr = SDB_STORE_ATTRIBUTE_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
int status = 0;
if ((! hostname) || (! service) || (! key) || (! value))
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store service attribute: "
+ "no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(hostname));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
+ attr.hostname = cname;
+ attr.parent_type = SDB_SERVICE;
+ attr.parent = service;
+ attr.key = key;
+ attr.value = *value;
+ attr.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_ATTRIBUTE, cname, SDB_SERVICE, service, key,
+ attr.last_update, &attr.interval)) {
+ free(cname);
+ return 1;
+ }
+ attr.backends = (const char * const *)backends;
+ get_backend(backends, &attr.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_service_attr(hostname, service,
- key, value, last_update, writer->w_user_data);
+ s = writer->impl.store_attribute(&attr, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+ free(cname);
return status;
} /* sdb_plugin_store_service_attribute */
sdb_plugin_store_metric_attribute(const char *hostname, const char *metric,
const char *key, const sdb_data_t *value, sdb_time_t last_update)
{
+ sdb_store_attribute_t attr = SDB_STORE_ATTRIBUTE_INIT;
+ char *backends[1];
+ char *cname;
+
sdb_llist_iter_t *iter;
int status = 0;
if ((! hostname) || (! metric) || (! key) || (! value))
return -1;
+ if (! sdb_llist_len(writer_list)) {
+ sdb_log(SDB_LOG_ERR, "Cannot store metric attribute: "
+ "no writers registered");
+ return -1;
+ }
+
+ cname = sdb_plugin_cname(strdup(hostname));
+ if (! cname) {
+ sdb_log(SDB_LOG_ERR, "strdup failed");
+ return -1;
+ }
+
+ attr.hostname = cname;
+ attr.parent_type = SDB_METRIC;
+ attr.parent = metric;
+ attr.key = key;
+ attr.value = *value;
+ attr.last_update = last_update ? last_update : sdb_gettime();
+ if (get_interval(SDB_ATTRIBUTE, cname, SDB_METRIC, metric, key,
+ attr.last_update, &attr.interval)) {
+ free(cname);
+ return 1;
+ }
+ attr.backends = (const char * const *)backends;
+ get_backend(backends, &attr.backends_num);
+
iter = sdb_llist_get_iter(writer_list);
while (sdb_llist_iter_has_next(iter)) {
writer_t *writer = WRITER(sdb_llist_iter_get_next(iter));
int s;
assert(writer);
- s = writer->impl.store_metric_attr(hostname, metric,
- key, value, last_update, writer->w_user_data);
+ s = writer->impl.store_attribute(&attr, writer->w_user_data);
if (((s > 0) && (status >= 0)) || (s < 0))
status = s;
}
sdb_llist_iter_destroy(iter);
+ free(cname);
return status;
} /* sdb_plugin_store_metric_attribute */