postgresql plugin: Added 'StoreRates' feature to writers.

Similar to other write plugins, this option causes counter values to be
converted to rates before submitting them to the database. The option defaults
to true.

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 7d287cc..6a1cdd2 100644 (file)
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -3735,6 +3735,12 @@ PostgreSQL database for this purpose. Any procedural language supported by
 PostgreSQL will do (see chapter "Server Programming" in the PostgreSQL manual
 for details).
 
+=item B<StoreRates> B<false>|B<true>
+
+If set to B<true> (the default), convert counter values to rates. If set to
+B<false> counter values are stored as is, i.E<nbsp>e. as an increasing integer
+number.
+
 =back
 
 The B<Database> block defines one PostgreSQL database for which to collect

diff --git a/src/postgresql.c b/src/postgresql.c
index 7bc450e..62a54da 100644 (file)
--- a/src/postgresql.c
+++ b/src/postgresql.c
@@ -42,6 +42,7 @@
 #include "configfile.h"
 #include "plugin.h"
 
+#include "utils_cache.h"
 #include "utils_db_query.h"
 #include "utils_complain.h"
 
@@ -110,6 +111,7 @@ typedef struct {
 typedef struct {
        char *name;
        char *statement;
+       _Bool store_rates;
 } c_psql_writer_t;
 
 typedef struct {
@@ -597,11 +599,13 @@ static char *values_name_to_sqlarray (const data_set_t *ds,
 } /* values_name_to_sqlarray */
 
 static char *values_to_sqlarray (const data_set_t *ds, const value_list_t *vl,
-               char *string, size_t string_len)
+               char *string, size_t string_len, _Bool store_rates)
 {
        char  *str_ptr;
        size_t str_len;
 
+       gauge_t *rates = NULL;
+
        int i;
 
        str_ptr = string;
@@ -610,9 +614,31 @@ static char *values_to_sqlarray (const data_set_t *ds, const value_list_t *vl,
        for (i = 0; i < vl->values_len; ++i) {
                int status;
 
+               if ((ds->ds[i].type != DS_TYPE_GAUGE)
+                               && (ds->ds[i].type != DS_TYPE_COUNTER)
+                               && (ds->ds[i].type != DS_TYPE_DERIVE)
+                               && (ds->ds[i].type != DS_TYPE_ABSOLUTE)) {
+                       log_err ("c_psql_write: Unknown data source type: %i",
+                                       ds->ds[i].type);
+                       sfree (rates);
+                       return NULL;
+               }
+
                if (ds->ds[i].type == DS_TYPE_GAUGE)
                        status = ssnprintf (str_ptr, str_len,
                                        ",%f", vl->values[i].gauge);
+               else if (store_rates) {
+                       if (rates == NULL)
+                               rates = uc_get_rate (ds, vl);
+
+                       if (rates == NULL) {
+                               log_err ("c_psql_write: Failed to determine rate");
+                               return NULL;
+                       }
+
+                       status = ssnprintf (str_ptr, str_len,
+                                       ",%lf", rates[i]);
+               }
                else if (ds->ds[i].type == DS_TYPE_COUNTER)
                        status = ssnprintf (str_ptr, str_len,
                                        ",%llu", vl->values[i].counter);
@@ -622,14 +648,11 @@ static char *values_to_sqlarray (const data_set_t *ds, const value_list_t *vl,
                else if (ds->ds[i].type == DS_TYPE_ABSOLUTE)
                        status = ssnprintf (str_ptr, str_len,
                                        ",%"PRIu64, vl->values[i].absolute);
-               else {
-                       log_err ("c_psql_write: Unknown data source type: %i",
-                                       ds->ds[i].type);
-                       return NULL;
-               }
 
-               if (status < 1)
-                       return NULL;
+               if (status < 1) {
+                       str_len = 0;
+                       break;
+               }
                else if ((size_t)status >= str_len) {
                        str_len = 0;
                        break;
@@ -640,6 +663,8 @@ static char *values_to_sqlarray (const data_set_t *ds, const value_list_t *vl,
                }
        }
 
+       sfree (rates);
+
        if (str_len <= 2) {
                log_err ("c_psql_write: Failed to stringify value list");
                return NULL;
@@ -685,9 +710,6 @@ static int c_psql_write (const data_set_t *ds, const value_list_t *vl,
                                values_name_str, sizeof (values_name_str)) == NULL)
                return -1;
 
-       if (values_to_sqlarray (ds, vl, values_str, sizeof (values_str)) == NULL)
-               return -1;
-
 #define VALUE_OR_NULL(v) ((((v) == NULL) || (*(v) == '\0')) ? NULL : (v))
 
        params[0] = time_str;
@@ -697,7 +719,6 @@ static int c_psql_write (const data_set_t *ds, const value_list_t *vl,
        params[4] = vl->type;
        params[5] = VALUE_OR_NULL(vl->type_instance);
        params[6] = values_name_str;
-       params[7] = values_str;
 
 #undef VALUE_OR_NULL
 
@@ -714,6 +735,13 @@ static int c_psql_write (const data_set_t *ds, const value_list_t *vl,
 
                writer = db->writers[i];
 
+               if (values_to_sqlarray (ds, vl,
+                                       values_str, sizeof (values_str),
+                                       writer->store_rates) == NULL)
+                       return -1;
+
+               params[7] = values_str;
+
                res = PQexecParams (db->conn, writer->statement,
                                STATIC_ARRAY_SIZE (params), NULL,
                                (const char *const *)params,
@@ -903,12 +931,15 @@ static int c_psql_config_writer (oconfig_item_t *ci)
 
        writer->name = sstrdup (ci->values[0].value.string);
        writer->statement = NULL;
+       writer->store_rates = 1;
 
        for (i = 0; i < ci->children_num; ++i) {
                oconfig_item_t *c = ci->children + i;
 
                if (strcasecmp ("Statement", c->key) == 0)
                        status = cf_util_get_string (c, &writer->statement);
+               if (strcasecmp ("StoreRates", c->key) == 0)
+                       status = cf_util_get_boolean (c, &writer->store_rates);
                else
                        log_warn ("Ignoring unknown config key \"%s\".", c->key);
        }