nginx plugin: Added a plugin to collect `nginx' statistics.

nginx is a lightweight webserver and (reverse) proxy and apparently very
popular in Russia. This plugin queries it's status page, parses it and submits
it to collectd, very similar to the apache plugin.

diff --git a/configure.in b/configure.in
index 767fd98707ca4162b3a02ac4bb9c8fcc89462ac3..ce8698bdd67747869f070c232090aa448c97c88e 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -1071,6 +1071,7 @@ AC_COLLECTD([memory],    [disable], [module], [memory statistics])
 AC_COLLECTD([multimeter],[disable], [module], [multimeter statistics])
 AC_COLLECTD([mysql],     [disable], [module], [mysql statistics])
 AC_COLLECTD([nfs],       [disable], [module], [nfs statistics])
+AC_COLLECTD([nginx],     [disable], [module], [nginx statistics])
 AC_COLLECTD([ntpd],      [disable], [module], [nfs statistics])
 AC_COLLECTD([ping],      [disable], [module], [ping statistics])
 AC_COLLECTD([processes], [disable], [module], [processes statistics])
@@ -1124,6 +1125,7 @@ Configuration:
     multimeter  . . . . $enable_multimeter
     mysql . . . . . . . $enable_mysql
     nfs . . . . . . . . $enable_nfs
+    nginx . . . . . . . $enable_nginx
     ntpd  . . . . . . . $enable_ntpd
     ping  . . . . . . . $enable_ping
     processes . . . . . $enable_processes

diff --git a/src/Makefile.am b/src/Makefile.am
index 58cc0fe2a6ed845c9c19f7df10a50f0d4c5189b9..85c5f589682ea66d624848611bc5e6ba1c7fbc61 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -286,6 +286,17 @@ collectd_LDADD += "-dlopen" nfs.la
 collectd_DEPENDENCIES += nfs.la
 endif
 
+if BUILD_MODULE_NGINX
+pkglib_LTLIBRARIES += nginx.la
+nginx_la_SOURCES = nginx.c
+nginx_la_LDFLAGS = -module -avoid-version
+if BUILD_WITH_LIBCURL
+nginx_la_LDFLAGS += $(BUILD_WITH_LIBCURL_LIBS)
+endif
+collectd_LDADD += "-dlopen" nginx.la
+collectd_DEPENDENCIES += nginx.la
+endif
+
 if BUILD_MODULE_NTPD
 pkglib_LTLIBRARIES += ntpd.la
 ntpd_la_SOURCES = ntpd.c

diff --git a/src/nginx.c b/src/nginx.c
new file mode 100644 (file)
index 0000000..e5848ee
--- /dev/null
+++ b/src/nginx.c
@@ -0,0 +1,296 @@
+/**
+ * collectd - src/nginx.c
+ * Copyright (C) 2006,2007  Florian octo Forster
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ *
+ * Authors:
+ *   Florian octo Forster <octo at verplant.org>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "plugin.h"
+#include "utils_debug.h"
+#include "configfile.h"
+
+#define MODULE_NAME "nginx"
+
+#if HAVE_LIBCURL && HAVE_CURL_CURL_H
+#  define NGINX_HAVE_READ 1
+#  include <curl/curl.h>
+#else
+#  define NGINX_HAVE_READ 0
+#endif
+
+static char *url    = NULL;
+static char *user   = NULL;
+static char *pass   = NULL;
+static char *cacert = NULL;
+
+#if HAVE_LIBCURL
+static CURL *curl = NULL;
+
+#define ABUFFER_SIZE 16384
+static char nginx_buffer[ABUFFER_SIZE];
+static int  nginx_buffer_len = 0;
+static char nginx_curl_error[CURL_ERROR_SIZE];
+#endif /* HAVE_LIBCURL */
+
+static char *connections_file = "nginx/nginx_connections-%s.rrd";
+static char *connections_ds_def[] =
+{
+  "DS:value:GAUGE:"COLLECTD_HEARTBEAT":0:U",
+  NULL
+};
+static int connections_ds_num = 1;
+
+/* Limit to 2^20 requests/s */
+static char *requests_file = "nginx/nginx_requests.rrd";
+static char *requests_ds_def[] =
+{
+  "DS:value:COUNTER:"COLLECTD_HEARTBEAT":0:1048576",
+  NULL
+};
+static int requests_ds_num = 1;
+
+static char *config_keys[] =
+{
+  "URL",
+  "User",
+  "Password",
+  "CACert",
+  NULL
+};
+static int config_keys_num = 4;
+
+#if HAVE_LIBCURL
+static size_t nginx_curl_callback (void *buf, size_t size, size_t nmemb, void *stream)
+{
+  size_t len = size * nmemb;
+
+  if ((nginx_buffer_len + len) >= ABUFFER_SIZE)
+  {
+    len = (ABUFFER_SIZE - 1) - nginx_buffer_len;
+  }
+
+  if (len <= 0)
+    return (len);
+
+  memcpy (nginx_buffer + nginx_buffer_len, (char *) buf, len);
+  nginx_buffer_len += len;
+  nginx_buffer[nginx_buffer_len] = '\0';
+
+  return (len);
+}
+#endif /* HAVE_LIBCURL */
+
+static int config_set (char **var, char *value)
+{
+  if (*var != NULL)
+  {
+    free (*var);
+    *var = NULL;
+  }
+
+  if ((*var = strdup (value)) == NULL)
+    return (1);
+  else
+    return (0);
+}
+
+static int config (char *key, char *value)
+{
+  if (strcasecmp (key, "url") == 0)
+    return (config_set (&url, value));
+  else if (strcasecmp (key, "user") == 0)
+    return (config_set (&user, value));
+  else if (strcasecmp (key, "password") == 0)
+    return (config_set (&pass, value));
+  else if (strcasecmp (key, "cacert") == 0)
+    return (config_set (&cacert, value));
+  else
+    return (-1);
+}
+
+static void init (void)
+{
+#if HAVE_LIBCURL
+  static char credentials[1024];
+
+  if (curl != NULL)
+  {
+    curl_easy_cleanup (curl);
+  }
+
+  if ((curl = curl_easy_init ()) == NULL)
+  {
+    syslog (LOG_ERR, "nginx: `curl_easy_init' failed.");
+    return;
+  }
+
+  curl_easy_setopt (curl, CURLOPT_WRITEFUNCTION, nginx_curl_callback);
+  curl_easy_setopt (curl, CURLOPT_USERAGENT, PACKAGE_NAME"/"PACKAGE_VERSION);
+  curl_easy_setopt (curl, CURLOPT_ERRORBUFFER, nginx_curl_error);
+
+  if (user != NULL)
+  {
+    if (snprintf (credentials, 1024, "%s:%s", user, pass == NULL ? "" : pass) >= 1024)
+    {
+      syslog (LOG_ERR, "nginx: Credentials would have been truncated.");
+      return;
+    }
+
+    curl_easy_setopt (curl, CURLOPT_USERPWD, credentials);
+  }
+
+  if (url != NULL)
+  {
+    curl_easy_setopt (curl, CURLOPT_URL, url);
+  }
+
+  if (cacert != NULL)
+  {
+    curl_easy_setopt (curl, CURLOPT_CAINFO, cacert);
+  }
+#endif /* HAVE_LIBCURL */
+} /* void init */
+
+static void connections_write (char *host, char *inst, char *val)
+{
+  char buf[1024];
+
+  if (snprintf (buf, 1024, connections_file, inst) >= 1024)
+    return;
+
+  rrd_update_file (host, buf, val,
+      connections_ds_def, connections_ds_num);
+}
+
+static void requests_write (char *host, char *inst, char *val)
+{
+  rrd_update_file (host, requests_file, val,
+      requests_ds_def, requests_ds_num);
+}
+
+#if NGINX_HAVE_READ
+static void submit (char *type, char *inst, long long value)
+{
+  char buf[1024];
+  int  status;
+
+  DBG ("type = %s; inst = %s; value = %lli;",
+      type, (inst == NULL) ? "(nil)" : inst, value);
+
+  status = snprintf (buf, 1024, "%u:%lli", (unsigned int) curtime, value);
+  if ((status < 0) || (status >= 1024))
+  {
+    syslog (LOG_ERR, "nginx: snprintf failed");
+    return;
+  }
+
+  plugin_submit (type, inst, buf);
+}
+
+static void nginx_read (void)
+{
+  int i;
+
+  char *ptr;
+  char *lines[16];
+  int   lines_num = 0;
+
+  char *fields[16];
+  int   fields_num;
+
+  if (curl == NULL)
+    return;
+  if (url == NULL)
+    return;
+
+  nginx_buffer_len = 0;
+  if (curl_easy_perform (curl) != 0)
+  {
+    syslog (LOG_WARNING, "nginx: curl_easy_perform failed: %s", nginx_curl_error);
+    return;
+  }
+
+  ptr = nginx_buffer;
+  while ((lines[lines_num] = strtok (ptr, "\n\r")) != NULL)
+  {
+    ptr = NULL;
+    lines_num++;
+
+    if (lines_num >= 16)
+      break;
+  }
+
+  /*
+   * Active connections: 291
+   * server accepts handled requests
+   *  16630948 16630948 31070465
+   * Reading: 6 Writing: 179 Waiting: 106
+   */
+  for (i = 0; i < lines_num; i++)
+  {
+    fields_num = strsplit (lines[i], fields,
+       (sizeof (fields) / sizeof (fields[0])));
+
+    if (fields_num == 3)
+    {
+      if ((strcmp (fields[0], "Active") == 0)
+         && (strcmp (fields[1], "connections:") == 0))
+      {
+       submit ("nginx_connections", "active", atoll (fields[2]));
+      }
+      else if ((atoll (fields[0]) != 0)
+         && (atoll (fields[1]) != 0)
+         && (atoll (fields[2]) != 0))
+      {
+       submit ("nginx_requests", NULL, atoll (fields[2]));
+      }
+    }
+    else if (fields_num == 6)
+    {
+      if ((strcmp (fields[0], "Reading:") == 0)
+         && (strcmp (fields[2], "Writing:") == 0)
+         && (strcmp (fields[4], "Waiting:") == 0))
+      {
+       submit ("nginx_connections", "reading", atoll (fields[1]));
+       submit ("nginx_connections", "writing", atoll (fields[3]));
+       submit ("nginx_connections", "waiting", atoll (fields[5]));
+      }
+    }
+  }
+
+  nginx_buffer_len = 0;
+}
+#else
+#  define nginx_read NULL
+#endif /* NGINX_HAVE_READ */
+
+void module_register (void)
+{
+  plugin_register (MODULE_NAME, init, nginx_read, NULL);
+  plugin_register ("nginx_requests",   NULL, NULL, requests_write);
+  plugin_register ("nginx_connections", NULL, NULL, connections_write);
+  cf_register (MODULE_NAME, config, config_keys, config_keys_num);
+}
+
+#undef MODULE_NAME
+
+/*
+ * vim: set shiftwidth=2 softtabstop=2 tabstop=8 :
+ */