write_http plugin: Implement support for multiple destinations.
authorFlorian Forster <octo@leeloo.lan.home.verplant.org>
Sat, 29 Aug 2009 08:33:19 +0000 (10:33 +0200)
committerFlorian Forster <octo@leeloo.lan.home.verplant.org>
Sat, 29 Aug 2009 08:33:19 +0000 (10:33 +0200)
src/collectd.conf.in
src/collectd.conf.pod
src/plugin.c
src/write_http.c

index 19b57af..9a54245 100644 (file)
@@ -127,6 +127,7 @@ FQDNLookup   true
 #@BUILD_PLUGIN_VMEM_TRUE@LoadPlugin vmem
 #@BUILD_PLUGIN_VSERVER_TRUE@LoadPlugin vserver
 #@BUILD_PLUGIN_WIRELESS_TRUE@LoadPlugin wireless
+#@BUILD_PLUGIN_WRITE_HTTP_TRUE@LoadPlugin write_http
 #@BUILD_PLUGIN_XMMS_TRUE@LoadPlugin xmms
 
 ##############################################################################
@@ -713,6 +714,13 @@ FQDNLookup   true
 #      Verbose false
 #</Plugin>
 
+#<Plugin write_http>
+#      <URL "http://example.com/collectd-post">
+#              User "collectd"
+#              Password "weCh3ik0"
+#      </URL>
+#</Plugin>
+
 ##############################################################################
 # Filter configuration                                                       #
 #----------------------------------------------------------------------------#
index e794319..786572c 100644 (file)
@@ -3454,15 +3454,23 @@ iptables to feed data for the guest IPs into the iptables plugin.
 =head2 Plugin C<write_http>
 
 This output plugin submits values to an http server by POST them using the
-PUTVAL plain-text protocol.
+PUTVAL plain-text protocol. Each destination you want to post data to needs to
+have one B<URL> block, within which the destination can be configured further,
+for example by specifying authentication data.
 
-The following options are accepted by the I<write_http plugin>:
+Synopsis:
 
-=over 4
+ <Plugin "write_http">
+   <URL "http://example.com/post-collectd">
+     User "collectd"
+     Password "weCh3ik0"
+   </URL>
+ </Plugin>
 
-=item B<URL> I<http://example.com/collectd-import>
+B<URL> blocks need one string argument which is used as the URL to which data
+is posted. The following options are understood within B<URL> blocks.
 
-Set the URL location where values will be sent.
+=over 4
 
 =item B<User> I<Username>
 
index b150cf6..7f37fa7 100644 (file)
@@ -1205,8 +1205,14 @@ void plugin_shutdown_all (void)
                (*callback) ();
        }
 
-       destroy_all_callbacks (&list_write);
+       /* Write plugins which use the `user_data' pointer usually need the
+        * same data available to the flush callback. If this is the case, set
+        * the free_function to NULL when registering the flush callback and to
+        * the real free function when registering the write callback. This way
+        * the data isn't freed twice. */
        destroy_all_callbacks (&list_flush);
+       destroy_all_callbacks (&list_write);
+
        destroy_all_callbacks (&list_notification);
        destroy_all_callbacks (&list_shutdown);
        destroy_all_callbacks (&list_log);
index 27d1842..912c92d 100644 (file)
 /*
  * Private variables
  */
-static const char *config_keys[] =
+struct wh_callback_s
 {
-        "URL", "User", "Password"
-};
-static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
+        char *location;
 
-static char *location   = NULL;
+        char *user;
+        char *pass;
+        char *credentials;
 
-char *user;
-char *pass;
-char *credentials;
+        CURL *curl;
+        char curl_errbuf[CURL_ERROR_SIZE];
 
-CURL *curl;
-char curl_errbuf[CURL_ERROR_SIZE];
+        char   send_buffer[4096];
+        size_t send_buffer_free;
+        size_t send_buffer_fill;
+        time_t send_buffer_init_time;
 
-#define SEND_BUFFER_SIZE 4096
-static char   send_buffer[SEND_BUFFER_SIZE];
-static size_t send_buffer_free;
-static size_t send_buffer_fill;
-static time_t send_buffer_init_time;
+        pthread_mutex_t send_lock;
+};
+typedef struct wh_callback_s wh_callback_t;
 
-static pthread_mutex_t  send_lock = PTHREAD_MUTEX_INITIALIZER;
+static void wh_reset_buffer (wh_callback_t *cb)  /* {{{ */
+{
+        memset (cb->send_buffer, 0, sizeof (cb->send_buffer));
+        cb->send_buffer_free = sizeof (cb->send_buffer);
+        cb->send_buffer_fill = 0;
+        cb->send_buffer_init_time = time (NULL);
+} /* }}} wh_reset_buffer */
 
-static void wh_init_buffer (void)  /* {{{ */
+static int wh_send_buffer (wh_callback_t *cb) /* {{{ */
 {
-        memset (send_buffer, 0, sizeof (send_buffer));
-        send_buffer_free = sizeof (send_buffer);
-        send_buffer_fill = 0;
-        send_buffer_init_time = time (NULL);
-} /* }}} wh_init_buffer */
+        int status = 0;
+
+        curl_easy_setopt (cb->curl, CURLOPT_POSTFIELDS, cb->send_buffer);
+        status = curl_easy_perform (cb->curl);
+        if (status != 0)
+        {
+                ERROR ("write_http plugin: curl_easy_perform failed with "
+                                "staus %i: %s",
+                                status, cb->curl_errbuf);
+        }
+        return (status);
+} /* }}} wh_send_buffer */
 
-static int wh_init(void) /* {{{ */
+static int wh_callback_init (wh_callback_t *cb) /* {{{ */
 {
+        struct curl_slist *headers;
 
-        curl = curl_easy_init ();
+        if (cb->curl != NULL)
+                return (0);
 
-        if (curl == NULL)
+        cb->curl = curl_easy_init ();
+        if (cb->curl == NULL)
         {
                 ERROR ("curl plugin: curl_easy_init failed.");
                 return (-1);
         }
 
-        struct curl_slist *headers=NULL;
+        curl_easy_setopt (cb->curl, CURLOPT_USERAGENT, PACKAGE_NAME"/"PACKAGE_VERSION);
 
-        curl_easy_setopt (curl, CURLOPT_USERAGENT, PACKAGE_NAME"/"PACKAGE_VERSION);
+        headers = NULL;
+        headers = curl_slist_append (headers, "Accept:  */*");
+        headers = curl_slist_append (headers, "Content-Type: text/plain");
+        curl_easy_setopt (cb->curl, CURLOPT_HTTPHEADER, headers);
 
-        headers = curl_slist_append(headers, "Accept:  */*");
-        headers = curl_slist_append(headers, "Content-Type: text/plain");
-        curl_easy_setopt (curl, CURLOPT_HTTPHEADER, headers);
+        curl_easy_setopt (cb->curl, CURLOPT_ERRORBUFFER, cb->curl_errbuf);
+        curl_easy_setopt (cb->curl, CURLOPT_URL, cb->location);
 
-        curl_easy_setopt (curl, CURLOPT_ERRORBUFFER, curl_errbuf);
-        curl_easy_setopt (curl, CURLOPT_URL, location);
-
-        if (user != NULL)
+        if (cb->user != NULL)
         {
                 size_t credentials_size;
 
-                credentials_size = strlen (user) + 2;
-                if (pass != NULL)
-                        credentials_size += strlen (pass);
+                credentials_size = strlen (cb->user) + 2;
+                if (cb->pass != NULL)
+                        credentials_size += strlen (cb->pass);
 
-                credentials = (char *) malloc (credentials_size);
-                if (credentials == NULL)
+                cb->credentials = (char *) malloc (credentials_size);
+                if (cb->credentials == NULL)
                 {
                         ERROR ("curl plugin: malloc failed.");
                         return (-1);
                 }
 
-                ssnprintf (credentials, credentials_size, "%s:%s",
-                                user, (pass == NULL) ? "" : pass);
-                curl_easy_setopt (curl, CURLOPT_USERPWD, credentials);
-                curl_easy_setopt (curl, CURLOPT_HTTPAUTH, CURLAUTH_DIGEST);
+                ssnprintf (cb->credentials, credentials_size, "%s:%s",
+                                cb->user, (cb->pass == NULL) ? "" : cb->pass);
+                curl_easy_setopt (cb->curl, CURLOPT_USERPWD, cb->credentials);
+                curl_easy_setopt (cb->curl, CURLOPT_HTTPAUTH, CURLAUTH_DIGEST);
         }
 
-        wh_init_buffer ();
+        wh_reset_buffer (cb);
 
         return (0);
-} /* }}} */
+} /* }}} int wh_callback_init */
+
+static int wh_flush_nolock (int timeout, wh_callback_t *cb) /* {{{ */
+{
+        int status;
+
+        DEBUG ("write_http plugin: wh_flush_nolock: timeout = %i; "
+                        "send_buffer_fill = %zu;",
+                        timeout, cb->send_buffer_fill);
+
+        if (timeout > 0)
+        {
+                time_t now;
+
+                now = time (NULL);
+                if ((cb->send_buffer_init_time + timeout) > now)
+                        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);
+
+        return (status);
+} /* }}} wh_flush_nolock */
+
+static int wh_flush (int timeout, /* {{{ */
+                const char *identifier __attribute__((unused)),
+                user_data_t *user_data)
+{
+        wh_callback_t *cb;
+        int status;
+
+        if (user_data == NULL)
+                return (-EINVAL);
+
+        cb = user_data->data;
+
+        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 = wh_flush_nolock (timeout, cb);
+        pthread_mutex_unlock (&cb->send_lock);
+
+        return (status);
+} /* }}} int wh_flush */
+
+static void wh_callback_free (void *data) /* {{{ */
+{
+        wh_callback_t *cb;
+
+        if (data == NULL)
+                return;
+
+        cb = data;
+
+        wh_flush_nolock (/* timeout = */ -1, cb);
+
+        curl_easy_cleanup (cb->curl);
+        sfree (cb->location);
+        sfree (cb->user);
+        sfree (cb->pass);
+        sfree (cb->credentials);
+
+        sfree (cb);
+} /* }}} void wh_callback_free */
 
 static int wh_value_list_to_string (char *buffer, /* {{{ */
                 size_t buffer_size,
@@ -165,132 +259,35 @@ static int wh_value_list_to_string (char *buffer, /* {{{ */
 return (0);
 } /* }}} int wh_value_list_to_string */
 
-static int wh_config (const char *key, const char *value) /* {{{ */
-{
-        if (strcasecmp ("URL", key) == 0)
-        {
-                if (location != NULL)
-                        free (location);
-                location = strdup (value);
-                if (location != NULL)
-                {
-                        int len = strlen (location);
-                        while ((len > 0) && (location[len - 1] == '/'))
-                        {
-                                len--;
-                                location[len] = '\0';
-                        }
-                        if (len <= 0)
-                        {
-                                free (location);
-                                location = NULL;
-                        }
-                }
-        }
-        else if (strcasecmp ("User", key) == 0)
-        {
-                if (user != NULL)
-                        free (user);
-                user = strdup (value);
-                if (user != NULL)
-                {
-                        int len = strlen (user);
-                        while ((len > 0) && (user[len - 1] == '/'))
-                        {
-                                len--;
-                                user[len] = '\0';
-                        }
-                        if (len <= 0)
-                        {
-                                free (user);
-                                user = NULL;
-                        }
-                }
-        }
-        else if (strcasecmp ("Password", key) == 0)
-        {
-                if (pass != NULL)
-                        free (pass);
-                pass = strdup (value);
-                if (pass != NULL)
-                {
-                        int len = strlen (pass);
-                        while ((len > 0) && (pass[len - 1] == '/'))
-                        {
-                                len--;
-                                pass[len] = '\0';
-                        }
-                        if (len <= 0)
-                        {
-                                free (pass);
-                                pass = NULL;
-                        }
-                }
-        }
-        else
-        {
-                return (-1);
-        }
-        return (0);
-} /* }}} int wh_config */
-
-static int wh_send_buffer (char *buffer) /* {{{ */
-{
-        int status = 0;
-
-        curl_easy_setopt (curl, CURLOPT_POSTFIELDS, buffer);
-        status = curl_easy_perform (curl);
-        if (status != 0)
-        {
-                ERROR ("write_http plugin: curl_easy_perform failed with "
-                                "staus %i: %s",
-                                status, curl_errbuf);
-        }
-        return (status);
-} /* }}} wh_send_buffer */
-
-static int wh_flush_nolock (int timeout) /* {{{ */
+static int config_set_string (char **ret_string, /* {{{ */
+                oconfig_item_t *ci)
 {
-        int status;
+        char *string;
 
-        DEBUG ("write_http plugin: wh_flush_nolock: timeout = %i; "
-                        "send_buffer =\n  %s", timeout, send_buffer);
-
-        if (timeout > 0)
+        if ((ci->values_num != 1)
+                        || (ci->values[0].type != OCONFIG_TYPE_STRING))
         {
-                time_t now;
-
-                now = time (NULL);
-                if ((send_buffer_init_time + timeout) > now)
-                        return (0);
+                WARNING ("write_http plugin: The `%s' config option "
+                                "needs exactly one string argument.", ci->key);
+                return (-1);
         }
 
-        if (send_buffer_fill <= 0)
+        string = strdup (ci->values[0].value.string);
+        if (string == NULL)
         {
-                send_buffer_init_time = time (NULL);
-                return (0);
+                ERROR ("write_http plugin: strdup failed.");
+                return (-1);
         }
 
-        status = wh_send_buffer (send_buffer);
-        wh_init_buffer ();
+        if (*ret_string != NULL)
+                free (*ret_string);
+        *ret_string = string;
 
-        return (status);
-} /* }}} wh_flush_nolock */
-
-static int wh_flush (int timeout, /* {{{ */
-                const char *identifier __attribute__((unused)),
-                user_data_t *user_data __attribute__((unused)))
-{
-        int status;
-
-        pthread_mutex_lock (&send_lock);
-        status = wh_flush_nolock (timeout);
-        pthread_mutex_unlock (&send_lock);
-
-        return (status);
-} /* }}} int wh_flush */
+        return (0);
+} /* }}} int config_set_string */
 
-static int wh_write_command (const data_set_t *ds, const value_list_t *vl) /* {{{ */
+static int wh_write_command (const data_set_t *ds, const value_list_t *vl, /* {{{ */
+                wh_callback_t *cb)
 {
         char key[10*DATA_MAX_NAME_LEN];
         char values[512];
@@ -331,56 +328,136 @@ static int wh_write_command (const data_set_t *ds, const value_list_t *vl) /* {{
                 return (-1);
         }
 
-        pthread_mutex_lock (&send_lock);
+        pthread_mutex_lock (&cb->send_lock);
 
-        /* Check if we have enough space for this command. */
-        if (command_len >= send_buffer_free)
+        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);
+                }
+        }
+
+        if (command_len >= cb->send_buffer_free)
         {
-                status = wh_flush_nolock (/* timeout = */ -1);
+                status = wh_flush_nolock (/* timeout = */ -1, cb);
                 if (status != 0)
                 {
-                        pthread_mutex_unlock (&send_lock);
-                        return status;
+                        pthread_mutex_unlock (&cb->send_lock);
+                        return (status);
                 }
         }
-        assert (command_len < send_buffer_free);
+        assert (command_len < cb->send_buffer_free);
 
         /* `command_len + 1' because `command_len' does not include the
          * trailing null byte. Neither does `send_buffer_fill'. */
-        memcpy (send_buffer + send_buffer_fill, command, command_len + 1);
-        send_buffer_fill += command_len;
-        send_buffer_free -= command_len;
+        memcpy (cb->send_buffer + cb->send_buffer_fill,
+                        command, command_len + 1);
+        cb->send_buffer_fill += command_len;
+        cb->send_buffer_free -= command_len;
+
+        DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%) \"%s\"",
+                        cb->location,
+                        cb->send_buffer_fill, sizeof (cb->send_buffer),
+                        100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)),
+                        command);
 
-        pthread_mutex_unlock (&send_lock);
+        /* Check if we have enough space for this command. */
+        pthread_mutex_unlock (&cb->send_lock);
 
         return (0);
 } /* }}} int wh_write_command */
 
 static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
-                user_data_t __attribute__((unused)) *user_data)
+                user_data_t *user_data)
 {
+        wh_callback_t *cb;
         int status;
 
-        status = wh_write_command (ds, vl);
+        if (user_data == NULL)
+                return (-EINVAL);
 
+        cb = user_data->data;
+
+        status = wh_write_command (ds, vl, cb);
         return (status);
 } /* }}} int wh_write */
 
-static int wh_shutdown (void) /* {{{ */
+static int wh_config_url (oconfig_item_t *ci) /* {{{ */
 {
-        wh_flush_nolock (/* timeout = */ -1);
-        curl_easy_cleanup(curl);
+        wh_callback_t *cb;
+        user_data_t user_data;
+        int i;
+
+        cb = malloc (sizeof (*cb));
+        if (cb == NULL)
+        {
+                ERROR ("write_http plugin: malloc failed.");
+                return (-1);
+        }
+        memset (cb, 0, sizeof (*cb));
+
+        pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
+
+        config_set_string (&cb->location, ci);
+        if (cb->location == NULL)
+                return (-1);
+
+        for (i = 0; i < ci->children_num; i++)
+        {
+                oconfig_item_t *child = ci->children + i;
+
+                if (strcasecmp ("User", child->key) == 0)
+                        config_set_string (&cb->user, child);
+                else if (strcasecmp ("Password", child->key) == 0)
+                        config_set_string (&cb->pass, child);
+                else
+                {
+                        ERROR ("write_http plugin: Invalid configuration "
+                                        "option: %s.", child->key);
+                }
+        }
+
+        DEBUG ("write_http: Registering write callback with URL %s",
+                        cb->location);
+
+        memset (&user_data, 0, sizeof (user_data));
+        user_data.data = cb;
+        user_data.free_func = NULL;
+        plugin_register_flush ("write_http", wh_flush, &user_data);
+
+        user_data.free_func = wh_callback_free;
+        plugin_register_write ("write_http", wh_write, &user_data);
+
         return (0);
-} /* }}} int wh_shutdown */
+} /* }}} int wh_config_url */
+
+static int wh_config (oconfig_item_t *ci) /* {{{ */
+{
+        int i;
+
+        for (i = 0; i < ci->children_num; i++)
+        {
+                oconfig_item_t *child = ci->children + i;
+
+                if (strcasecmp ("URL", child->key) == 0)
+                        wh_config_url (child);
+                else
+                {
+                        ERROR ("write_http plugin: Invalid configuration "
+                                        "option: %s.", child->key);
+                }
+        }
+
+        return (0);
+} /* }}} int wh_config */
 
 void module_register (void) /* {{{ */
 {
-        plugin_register_init("write_http", wh_init);
-        plugin_register_config ("write_http", wh_config,
-                        config_keys, config_keys_num);
-        plugin_register_write ("write_http", wh_write, /* user_data = */ NULL);
-        plugin_register_flush ("write_http", wh_flush, /* user_data = */ NULL);
-        plugin_register_shutdown("write_http", wh_shutdown);
+        plugin_register_complex_config ("write_http", wh_config);
 } /* }}} void module_register */
 
 /* vim: set fdm=marker sw=8 ts=8 tw=78 et : */