write_http plugin: Make it possible to send values as JSON.

[collectd.git] / src / write_http.c

diff --git a/src/write_http.c b/src/write_http.c
index 30693e0..f14636b 100644 (file)
--- a/src/write_http.c
+++ b/src/write_http.c
@@ -28,6 +28,7 @@
 #include "common.h"
 #include "utils_cache.h"
 #include "utils_parse_option.h"
+#include "utils_format_json.h"
 
 #if HAVE_PTHREAD_H
 # include <pthread.h>
@@ -49,6 +50,10 @@ struct wh_callback_s
         int   verify_host;
         char *cacert;
 
+#define WH_FORMAT_COMMAND 0
+#define WH_FORMAT_JSON    1
+        int format;
+
         CURL *curl;
         char curl_errbuf[CURL_ERROR_SIZE];
 
@@ -67,6 +72,13 @@ static void wh_reset_buffer (wh_callback_t *cb)  /* {{{ */
         cb->send_buffer_free = sizeof (cb->send_buffer);
         cb->send_buffer_fill = 0;
         cb->send_buffer_init_time = time (NULL);
+
+        if (cb->format == WH_FORMAT_JSON)
+        {
+                format_json_initialize (cb->send_buffer,
+                                &cb->send_buffer_fill,
+                                &cb->send_buffer_free);
+        }
 } /* }}} wh_reset_buffer */
 
 static int wh_send_buffer (wh_callback_t *cb) /* {{{ */
@@ -102,7 +114,10 @@ static int wh_callback_init (wh_callback_t *cb) /* {{{ */
 
         headers = NULL;
         headers = curl_slist_append (headers, "Accept:  */*");
-        headers = curl_slist_append (headers, "Content-Type: text/plain");
+        if (cb->format == WH_FORMAT_JSON)
+                headers = curl_slist_append (headers, "Content-Type: application/json");
+        else
+                headers = curl_slist_append (headers, "Content-Type: text/plain");
         headers = curl_slist_append (headers, "Expect:");
         curl_easy_setopt (cb->curl, CURLOPT_HTTPHEADER, headers);
 
@@ -158,14 +173,46 @@ static int wh_flush_nolock (int timeout, wh_callback_t *cb) /* {{{ */
                         return (0);
         }
 
-        if (cb->send_buffer_fill <= 0)
+        if (cb->format == WH_FORMAT_COMMAND)
         {
-                cb->send_buffer_init_time = time (NULL);
-                return (0);
+                if (cb->send_buffer_fill <= 0)
+                {
+                        cb->send_buffer_init_time = time (NULL);
+                        return (0);
+                }
+
+                status = wh_send_buffer (cb);
+                wh_reset_buffer (cb);
         }
+        else if (cb->format == WH_FORMAT_JSON)
+        {
+                if (cb->send_buffer_fill <= 2)
+                {
+                        cb->send_buffer_init_time = time (NULL);
+                        return (0);
+                }
 
-        status = wh_send_buffer (cb);
-        wh_reset_buffer (cb);
+                status = format_json_finalize (cb->send_buffer,
+                                &cb->send_buffer_fill,
+                                &cb->send_buffer_free);
+                if (status != 0)
+                {
+                        ERROR ("write_http: wh_flush_nolock: "
+                                        "format_json_finalize failed.");
+                        wh_reset_buffer (cb);
+                        return (status);
+                }
+
+                status = wh_send_buffer (cb);
+                wh_reset_buffer (cb);
+        }
+        else
+        {
+                ERROR ("write_http: wh_flush_nolock: "
+                                "Unknown format: %i",
+                                cb->format);
+                return (-1);
+        }
 
         return (status);
 } /* }}} wh_flush_nolock */
@@ -355,6 +402,60 @@ static int wh_write_command (const data_set_t *ds, const value_list_t *vl, /* {{
         return (0);
 } /* }}} int wh_write_command */
 
+static int wh_write_json (const data_set_t *ds, const value_list_t *vl, /* {{{ */
+                wh_callback_t *cb)
+{
+        int status;
+
+        pthread_mutex_lock (&cb->send_lock);
+
+        if (cb->curl == NULL)
+        {
+                status = wh_callback_init (cb);
+                if (status != 0)
+                {
+                        ERROR ("write_http plugin: wh_callback_init failed.");
+                        pthread_mutex_unlock (&cb->send_lock);
+                        return (-1);
+                }
+        }
+
+        status = format_json_value_list (cb->send_buffer,
+                        &cb->send_buffer_fill,
+                        &cb->send_buffer_free,
+                        ds, vl);
+        if (status == (-ENOMEM))
+        {
+                status = wh_flush_nolock (/* timeout = */ -1, cb);
+                if (status != 0)
+                {
+                        wh_reset_buffer (cb);
+                        pthread_mutex_unlock (&cb->send_lock);
+                        return (status);
+                }
+
+                status = format_json_value_list (cb->send_buffer,
+                                &cb->send_buffer_fill,
+                                &cb->send_buffer_free,
+                                ds, vl);
+        }
+        if (status != 0)
+        {
+                pthread_mutex_unlock (&cb->send_lock);
+                return (status);
+        }
+
+        DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%)",
+                        cb->location,
+                        cb->send_buffer_fill, sizeof (cb->send_buffer),
+                        100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)));
+
+        /* Check if we have enough space for this command. */
+        pthread_mutex_unlock (&cb->send_lock);
+
+        return (0);
+} /* }}} int wh_write_json */
+
 static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
                 user_data_t *user_data)
 {
@@ -366,7 +467,11 @@ static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 
         cb = user_data->data;
 
-        status = wh_write_command (ds, vl, cb);
+        if (cb->format == WH_FORMAT_JSON)
+                status = wh_write_json (ds, vl, cb);
+        else
+                status = wh_write_command (ds, vl, cb);
+
         return (status);
 } /* }}} int wh_write */
 
@@ -411,6 +516,34 @@ static int config_set_boolean (int *dest, oconfig_item_t *ci) /* {{{ */
         return (0);
 } /* }}} int config_set_boolean */
 
+static int config_set_format (wh_callback_t *cb, /* {{{ */
+                oconfig_item_t *ci)
+{
+        char *string;
+
+        if ((ci->values_num != 1)
+                        || (ci->values[0].type != OCONFIG_TYPE_STRING))
+        {
+                WARNING ("write_http plugin: The `%s' config option "
+                                "needs exactly one string argument.", ci->key);
+                return (-1);
+        }
+
+        string = ci->values[0].value.string;
+        if (strcasecmp ("Command", string) == 0)
+                cb->format = WH_FORMAT_COMMAND;
+        else if (strcasecmp ("JSON", string) == 0)
+                cb->format = WH_FORMAT_JSON;
+        else
+        {
+                ERROR ("write_http plugin: Invalid format string: %s",
+                                string);
+                return (-1);
+        }
+
+        return (0);
+} /* }}} int config_set_string */
+
 static int wh_config_url (oconfig_item_t *ci) /* {{{ */
 {
         wh_callback_t *cb;
@@ -431,6 +564,7 @@ static int wh_config_url (oconfig_item_t *ci) /* {{{ */
         cb->verify_peer = 1;
         cb->verify_host = 1;
         cb->cacert = NULL;
+        cb->format = WH_FORMAT_COMMAND;
         cb->curl = NULL;
 
         pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
@@ -453,6 +587,8 @@ static int wh_config_url (oconfig_item_t *ci) /* {{{ */
                         config_set_boolean (&cb->verify_host, child);
                 else if (strcasecmp ("CACert", child->key) == 0)
                         config_set_string (&cb->cacert, child);
+                else if (strcasecmp ("Format", child->key) == 0)
+                        config_set_format (cb, child);
                 else
                 {
                         ERROR ("write_http plugin: Invalid configuration "