write_graphite plugin: Implement the "AlwaysAppendDS" option.

Don't append DS name by default, except when there is more than one DS.
The "AlwaysAppendDS" option can be used to force the plugin to always
append the DS.

Change-Id: I0221bef49375e3b5c5de99bb8f5a9cd641b696c3

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 64ef7f2..18b7378 100644 (file)
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -4804,6 +4804,12 @@ If set to B<true>, convert counter values to rates. If set to B<false> (the
 default) counter values are stored as is, i.E<nbsp>e. as an increasing integer
 number.
 
+=item B<AlwaysAppendDS> B<false>|B<true>
+
+If set the B<true>, append the name of the I<Data Source> (DS) to the "metric"
+identifier. If set to B<false> (the default), this is only done when there is
+more than one DS.
+
 =back
 
 =head2 Plugin C<write_http>

diff --git a/src/write_graphite.c b/src/write_graphite.c
index fca40d1..2e4af22 100644 (file)
--- a/src/write_graphite.c
+++ b/src/write_graphite.c
@@ -54,15 +54,6 @@
 #include <sys/socket.h>
 #include <netdb.h>
 
-#ifndef WG_FORMAT_NAME
-#define WG_FORMAT_NAME(ret, ret_len, vl, cb, ds_name) \
-        wg_format_name (ret, ret_len, (vl)->host, \
-                         (vl)->plugin, (vl)->plugin_instance, \
-                         (vl)->type, (vl)->type_instance, \
-                         (cb)->prefix, (cb)->postfix, \
-                         ds_name, (cb)->escape_char)
-#endif
-
 #ifndef WG_DEFAULT_NODE
 # define WG_DEFAULT_NODE "localhost"
 #endif
@@ -93,6 +84,7 @@ struct wg_callback
     char     escape_char;
 
     _Bool    store_rates;
+    _Bool    always_append_ds;
 
     char     send_buf[WG_SEND_BUF_SIZE];
     size_t   send_buf_free;
@@ -380,73 +372,59 @@ static void wg_copy_escape_part (char *dst, const char *src, size_t dst_len,
 }
 
 static int wg_format_name (char *ret, int ret_len,
-        const char *hostname,
-        const char *plugin, const char *plugin_instance,
-        const char *type, const char *type_instance,
-        const char *prefix, const char *postfix,
-        const char *ds_name, char escape_char)
+        const value_list_t *vl,
+        const struct wg_callback *cb,
+        const char *ds_name)
 {
-    char n_hostname[DATA_MAX_NAME_LEN];
+    char n_host[DATA_MAX_NAME_LEN];
     char n_plugin[DATA_MAX_NAME_LEN];
     char n_plugin_instance[DATA_MAX_NAME_LEN];
     char n_type[DATA_MAX_NAME_LEN];
     char n_type_instance[DATA_MAX_NAME_LEN];
-    int  status;
 
-    assert (hostname != NULL);
-    assert (plugin != NULL);
-    assert (type != NULL);
-    assert (ds_name != NULL);
+    char *prefix;
+    char *postfix;
+
+    char tmp_plugin[2 * DATA_MAX_NAME_LEN + 1];
+    char tmp_type[2 * DATA_MAX_NAME_LEN + 1];
 
+    prefix = cb->prefix;
     if (prefix == NULL)
         prefix = "";
 
+    postfix = cb->postfix;
     if (postfix == NULL)
         postfix = "";
 
-    wg_copy_escape_part (n_hostname, hostname,
-            sizeof (n_hostname), escape_char);
-    wg_copy_escape_part (n_plugin, plugin,
-            sizeof (n_plugin), escape_char);
-    wg_copy_escape_part (n_plugin_instance, plugin_instance,
-            sizeof (n_plugin_instance), escape_char);
-    wg_copy_escape_part (n_type, type,
-            sizeof (n_type), escape_char);
-    wg_copy_escape_part (n_type_instance, type_instance,
-            sizeof (n_type_instance), escape_char);
-
-    if (n_plugin_instance[0] == '\0')
-    {
-        if (n_type_instance[0] == '\0')
-        {
-            status = ssnprintf (ret, ret_len, "%s%s%s.%s.%s.%s",
-                    prefix, n_hostname, postfix, n_plugin, n_type, ds_name);
-        }
-        else
-        {
-            status = ssnprintf (ret, ret_len, "%s%s%s.%s.%s-%s.%s",
-                    prefix, n_hostname, postfix, n_plugin, n_type,
-                    n_type_instance, ds_name);
-        }
-    }
+    wg_copy_escape_part (n_host, vl->host,
+            sizeof (n_host), cb->escape_char);
+    wg_copy_escape_part (n_plugin, vl->plugin,
+            sizeof (n_plugin), cb->escape_char);
+    wg_copy_escape_part (n_plugin_instance, vl->plugin_instance,
+            sizeof (n_plugin_instance), cb->escape_char);
+    wg_copy_escape_part (n_type, vl->type,
+            sizeof (n_type), cb->escape_char);
+    wg_copy_escape_part (n_type_instance, vl->type_instance,
+            sizeof (n_type_instance), cb->escape_char);
+
+    if (n_plugin_instance[0] != '\0')
+        ssnprintf (tmp_plugin, sizeof (tmp_plugin), "%s-%s",
+            n_plugin, n_plugin_instance);
     else
-    {
-        if (n_type_instance[0] == '\0')
-        {
-            status = ssnprintf (ret, ret_len, "%s%s%s.%s.%s.%s.%s",
-                    prefix, n_hostname, postfix, n_plugin,
-                    n_plugin_instance, n_type, ds_name);
-        }
-        else
-        {
-            status = ssnprintf (ret, ret_len, "%s%s%s.%s.%s.%s-%s.%s",
-                    prefix, n_hostname, postfix, n_plugin,
-                    n_plugin_instance, n_type, n_type_instance, ds_name);
-        }
-    }
+        sstrncpy (tmp_plugin, n_plugin, sizeof (tmp_plugin));
 
-    if ((status < 1) || (status >= ret_len))
-        return (-1);
+    if (n_type_instance[0] != '\0')
+        ssnprintf (tmp_type, sizeof (tmp_type), "%s-%s",
+            n_type, n_type_instance);
+    else
+        sstrncpy (tmp_type, n_type, sizeof (tmp_type));
+
+    if (ds_name != NULL)
+        ssnprintf (ret, ret_len, "%s%s%s.%s.%s.%s",
+            prefix, n_host, postfix, tmp_plugin, tmp_type, ds_name);
+    else
+        ssnprintf (ret, ret_len, "%s%s%s.%s.%s",
+            prefix, n_host, postfix, tmp_plugin, tmp_type);
 
     return (0);
 }
@@ -534,7 +512,7 @@ static int wg_write_messages (const data_set_t *ds, const value_list_t *vl,
         for (i = 0; i < ds->ds_num; i++)
         {
             /* Copy the identifier to `key' and escape it. */
-            status = WG_FORMAT_NAME (key, sizeof (key), vl, cb, ds->ds[i].name);
+            status = wg_format_name (key, sizeof (key), vl, cb, ds->ds[i].name);
             if (status != 0)
             {
                 ERROR ("write_graphite plugin: error with format_name");
@@ -566,7 +544,8 @@ static int wg_write_messages (const data_set_t *ds, const value_list_t *vl,
     else
     {
         /* Copy the identifier to `key' and escape it. */
-        status = WG_FORMAT_NAME (key, sizeof (key), vl, cb, NULL);
+        status = wg_format_name (key, sizeof (key), vl, cb,
+            cb->always_append_ds ? ds->ds[0].name : NULL);
         if (status != 0)
         {
             ERROR ("write_graphite plugin: error with format_name");
@@ -605,7 +584,7 @@ static int wg_write (const data_set_t *ds, const value_list_t *vl,
     int status;
 
     if (user_data == NULL)
-        return (-EINVAL);
+        return (EINVAL);
 
     cb = user_data->data;
 
@@ -665,6 +644,8 @@ static int wg_config_carbon (oconfig_item_t *ci)
             cf_util_get_string (child, &cb->postfix);
         else if (strcasecmp ("StoreRates", child->key) == 0)
             cf_util_get_boolean (child, &cb->store_rates);
+        else if (strcasecmp ("AlwaysAppendDS", child->key) == 0)
+            cf_util_get_boolean (child, &cb->always_append_ds);
         else if (strcasecmp ("EscapeCharacter", child->key) == 0)
             config_set_char (&cb->escape_char, child);
         else