--- /dev/null
+/**
+ * collectd - src/write_gcm.c
+ * ISC license
+ *
+ * Copyright (C) 2017 Florian Forster
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Authors:
+ * Florian Forster <octo at collectd.org>
+ **/
+
+#include "collectd.h"
+
+#include "common.h"
+#include "configfile.h"
+#include "plugin.h"
+#include "utils_format_gcm.h"
+#include "utils_gce.h"
+#include "utils_oauth.h"
+
+#include <curl/curl.h>
+#include <pthread.h>
+
+/*
+ * Private variables
+ */
+#ifndef GCM_API_URL
+#define GCM_API_URL "https://monitoring.googleapis.com/v3"
+#endif
+
+#ifndef MONITORING_SCOPE
+#define MONITORING_SCOPE "https://www.googleapis.com/auth/monitoring"
+#endif
+
+struct wg_callback_s {
+ /* config */
+ char *email;
+ char *project;
+ char *url;
+ gcm_resource_t *resource;
+
+ /* runtime */
+ oauth_t *auth;
+ gcm_output_t *formatter;
+ CURL *curl;
+ char curl_errbuf[CURL_ERROR_SIZE];
+ /* used by flush */
+ size_t timeseries_count;
+ cdtime_t send_buffer_init_time;
+
+ pthread_mutex_t lock;
+};
+typedef struct wg_callback_s wg_callback_t;
+
+struct wg_memory_s {
+ char *memory;
+ size_t size;
+};
+typedef struct wg_memory_s wg_memory_t;
+
+static size_t wg_write_memory_cb(void *contents, size_t size,
+ size_t nmemb, /* {{{ */
+ void *userp) {
+ size_t realsize = size * nmemb;
+ wg_memory_t *mem = (wg_memory_t *)userp;
+
+ if (0x7FFFFFF0 < mem->size || 0x7FFFFFF0 - mem->size < realsize) {
+ ERROR("integer overflow");
+ return 0;
+ }
+
+ mem->memory = (char *)realloc((void *)mem->memory, mem->size + realsize + 1);
+ if (mem->memory == NULL) {
+ /* out of memory! */
+ ERROR("wg_write_memory_cb: not enough memory (realloc returned NULL)");
+ return 0;
+ }
+
+ memcpy(&(mem->memory[mem->size]), contents, realsize);
+ mem->size += realsize;
+ mem->memory[mem->size] = 0;
+ return realsize;
+} /* }}} size_t wg_write_memory_cb */
+
+static char *wg_get_authorization_header(wg_callback_t *cb) { /* {{{ */
+ int status = 0;
+ char access_token[256];
+ char authorization_header[256];
+
+ assert((cb->auth != NULL) || gce_check());
+ if (cb->auth != NULL)
+ status = oauth_access_token(cb->auth, access_token, sizeof(access_token));
+ else
+ status = gce_access_token(cb->email, access_token, sizeof(access_token));
+ if (status != 0) {
+ ERROR("write_gcm plugin: Failed to get access token");
+ return NULL;
+ }
+
+ status = snprintf(authorization_header, sizeof(authorization_header),
+ "Authorization: Bearer %s", access_token);
+ if ((status < 1) || ((size_t)status >= sizeof(authorization_header)))
+ return NULL;
+
+ return strdup(authorization_header);
+} /* }}} char *wg_get_authorization_header */
+
+static int wg_call_metricdescriptor_create(wg_callback_t *cb,
+ char const *payload) {
+ /* {{{ */
+ char final_url[1024];
+ int status =
+ snprintf(final_url, sizeof(final_url), "%s/projects/%s/metricDescriptors",
+ cb->url, cb->project);
+ if ((status < 1) || ((size_t)status >= sizeof(final_url)))
+ return -1;
+
+ char *authorization_header = wg_get_authorization_header(cb);
+ if (authorization_header == NULL)
+ return -1;
+
+ struct curl_slist *headers = NULL;
+ headers = curl_slist_append(headers, "Content-Type: application/json");
+ headers = curl_slist_append(headers, authorization_header);
+
+ CURL *curl = curl_easy_init();
+ if (!curl) {
+ ERROR("write_gcm plugin: curl_easy_init failed.");
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return -1;
+ }
+
+ curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1L);
+ curl_easy_setopt(cb->curl, CURLOPT_USERAGENT,
+ PACKAGE_NAME "/" PACKAGE_VERSION);
+ char curl_errbuf[CURL_ERROR_SIZE];
+ curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, curl_errbuf);
+ curl_easy_setopt(curl, CURLOPT_URL, final_url);
+ curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+ curl_easy_setopt(curl, CURLOPT_POST, 1L);
+ curl_easy_setopt(curl, CURLOPT_POSTFIELDS, payload);
+
+ wg_memory_t res = {
+ .memory = NULL, .size = 0,
+ };
+ curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, wg_write_memory_cb);
+ curl_easy_setopt(curl, CURLOPT_WRITEDATA, &res);
+
+ status = curl_easy_perform(curl);
+ if (status != CURLE_OK) {
+ ERROR("write_gcm plugin: curl_easy_perform failed with status %d: %s",
+ status, curl_errbuf);
+ sfree(res.memory);
+ curl_easy_cleanup(curl);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return -1;
+ }
+
+ long http_code = 0;
+ curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
+ if ((http_code < 200) || (http_code >= 300)) {
+ ERROR("write_gcm plugin: POST request to %s failed: HTTP error %ld",
+ final_url, http_code);
+ INFO("write_gcm plugin: Server replied: %s", res.memory);
+ sfree(res.memory);
+ curl_easy_cleanup(curl);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return -1;
+ }
+
+ sfree(res.memory);
+ curl_easy_cleanup(curl);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return 0;
+} /* }}} int wg_call_metricdescriptor_create */
+
+static void wg_reset_buffer(wg_callback_t *cb) /* {{{ */
+{
+ cb->timeseries_count = 0;
+ cb->send_buffer_init_time = cdtime();
+} /* }}} wg_reset_buffer */
+
+static int wg_call_timeseries_write(wg_callback_t *cb,
+ char const *payload) /* {{{ */
+{
+ char final_url[1024];
+ int status = snprintf(final_url, sizeof(final_url),
+ "%s/projects/%s/timeSeries", cb->url, cb->project);
+ if ((status < 1) || ((size_t)status >= sizeof(final_url)))
+ return -1;
+
+ char *authorization_header = wg_get_authorization_header(cb);
+ if (authorization_header == NULL)
+ return -1;
+
+ struct curl_slist *headers = NULL;
+ headers = curl_slist_append(headers, authorization_header);
+ headers = curl_slist_append(headers, "Content-Type: application/json");
+
+ curl_easy_setopt(cb->curl, CURLOPT_URL, final_url);
+ curl_easy_setopt(cb->curl, CURLOPT_HTTPHEADER, headers);
+ curl_easy_setopt(cb->curl, CURLOPT_POST, 1L);
+ curl_easy_setopt(cb->curl, CURLOPT_POSTFIELDS, payload);
+
+ wg_memory_t res = {
+ .memory = NULL, .size = 0,
+ };
+ curl_easy_setopt(cb->curl, CURLOPT_WRITEFUNCTION, wg_write_memory_cb);
+ curl_easy_setopt(cb->curl, CURLOPT_WRITEDATA, &res);
+
+ status = curl_easy_perform(cb->curl);
+ if (status != CURLE_OK) {
+ ERROR("write_gcm plugin: curl_easy_perform failed with status %d: %s",
+ status, cb->curl_errbuf);
+ sfree(res.memory);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return -1;
+ }
+
+ long http_code = 0;
+ curl_easy_getinfo(cb->curl, CURLINFO_RESPONSE_CODE, &http_code);
+ if ((http_code < 200) || (http_code >= 300)) {
+ ERROR("write_gcm plugin: POST request to %s failed: HTTP error %ld",
+ final_url, http_code);
+ INFO("write_gcm plugin: Server replied: %s", res.memory);
+ sfree(res.memory);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return -1;
+ }
+
+ sfree(res.memory);
+ curl_slist_free_all(headers);
+ sfree(authorization_header);
+ return status;
+} /* }}} wg_call_timeseries_write */
+
+static int wg_callback_init(wg_callback_t *cb) /* {{{ */
+{
+ if (cb->curl != NULL)
+ return 0;
+
+ cb->formatter = gcm_output_create(cb->resource);
+ if (cb->formatter == NULL) {
+ ERROR("write_gcm plugin: gcm_output_create failed.");
+ return -1;
+ }
+
+ cb->curl = curl_easy_init();
+ if (cb->curl == NULL) {
+ ERROR("write_gcm plugin: curl_easy_init failed.");
+ return -1;
+ }
+
+ curl_easy_setopt(cb->curl, CURLOPT_NOSIGNAL, 1L);
+ curl_easy_setopt(cb->curl, CURLOPT_USERAGENT,
+ PACKAGE_NAME "/" PACKAGE_VERSION);
+ curl_easy_setopt(cb->curl, CURLOPT_ERRORBUFFER, cb->curl_errbuf);
+ wg_reset_buffer(cb);
+
+ return 0;
+} /* }}} int wg_callback_init */
+
+static int wg_flush_nolock(cdtime_t timeout, wg_callback_t *cb) /* {{{ */
+{
+ if (cb->timeseries_count == 0) {
+ cb->send_buffer_init_time = cdtime();
+ return 0;
+ }
+
+ /* timeout == 0 => flush unconditionally */
+ if (timeout > 0) {
+ cdtime_t now = cdtime();
+
+ if ((cb->send_buffer_init_time + timeout) > now)
+ return 0;
+ }
+
+ char *payload = gcm_output_reset(cb->formatter);
+ int status = wg_call_timeseries_write(cb, payload);
+ if (status != 0) {
+ ERROR("write_gcm plugin: Sending buffer failed with status %d.", status);
+ }
+
+ wg_reset_buffer(cb);
+ return status;
+} /* }}} wg_flush_nolock */
+
+static int wg_flush(cdtime_t timeout, /* {{{ */
+ const char *identifier __attribute__((unused)),
+ user_data_t *user_data) {
+ wg_callback_t *cb;
+ int status;
+
+ if (user_data == NULL)
+ return -EINVAL;
+
+ cb = user_data->data;
+
+ pthread_mutex_lock(&cb->lock);
+
+ if (cb->curl == NULL) {
+ status = wg_callback_init(cb);
+ if (status != 0) {
+ ERROR("write_gcm plugin: wg_callback_init failed.");
+ pthread_mutex_unlock(&cb->lock);
+ return -1;
+ }
+ }
+
+ status = wg_flush_nolock(timeout, cb);
+ pthread_mutex_unlock(&cb->lock);
+
+ return status;
+} /* }}} int wg_flush */
+
+static void wg_callback_free(void *data) /* {{{ */
+{
+ wg_callback_t *cb = data;
+ if (cb == NULL)
+ return;
+
+ gcm_output_destroy(cb->formatter);
+ cb->formatter = NULL;
+
+ sfree(cb->email);
+ sfree(cb->project);
+ sfree(cb->url);
+
+ oauth_destroy(cb->auth);
+ if (cb->curl) {
+ curl_easy_cleanup(cb->curl);
+ }
+
+ sfree(cb);
+} /* }}} void wg_callback_free */
+
+static int wg_metric_descriptors_create(wg_callback_t *cb, const data_set_t *ds,
+ const value_list_t *vl) {
+ /* {{{ */
+ for (size_t i = 0; i < ds->ds_num; i++) {
+ char buffer[4096];
+
+ int status =
+ gcm_format_metric_descriptor(buffer, sizeof(buffer), ds, vl, i);
+ if (status != 0) {
+ ERROR("write_gcm plugin: gcm_format_metric_descriptor failed with status "
+ "%d",
+ status);
+ return status;
+ }
+
+ status = wg_call_metricdescriptor_create(cb, buffer);
+ if (status != 0) {
+ ERROR("write_gcm plugin: wg_call_metricdescriptor_create failed with "
+ "status %d",
+ status);
+ return status;
+ }
+ }
+
+ return gcm_output_register_metric(cb->formatter, ds, vl);
+} /* }}} int wg_metric_descriptors_create */
+
+static int wg_write(const data_set_t *ds, const value_list_t *vl, /* {{{ */
+ user_data_t *user_data) {
+ wg_callback_t *cb = user_data->data;
+ if (cb == NULL)
+ return EINVAL;
+
+ pthread_mutex_lock(&cb->lock);
+
+ if (cb->curl == NULL) {
+ int status = wg_callback_init(cb);
+ if (status != 0) {
+ ERROR("write_gcm plugin: wg_callback_init failed.");
+ pthread_mutex_unlock(&cb->lock);
+ return status;
+ }
+ }
+
+ int status;
+ while (42) {
+ status = gcm_output_add(cb->formatter, ds, vl);
+ if (status == 0) { /* success */
+ break;
+ } else if (status == ENOBUFS) { /* success, flush */
+ wg_flush_nolock(0, cb);
+ status = 0;
+ break;
+ } else if (status == EEXIST) {
+ /* metric already in the buffer; flush and retry */
+ wg_flush_nolock(0, cb);
+ continue;
+ } else if (status == ENOENT) {
+ /* new metric, create metric descriptor first */
+ status = wg_metric_descriptors_create(cb, ds, vl);
+ if (status != 0) {
+ break;
+ }
+ continue;
+ } else {
+ break;
+ }
+ }
+
+ if (status == 0) {
+ cb->timeseries_count++;
+ }
+
+ pthread_mutex_unlock(&cb->lock);
+ return status;
+} /* }}} int wg_write */
+
+static void wg_check_scope(char const *email) /* {{{ */
+{
+ char *scope = gce_scope(email);
+ if (scope == NULL) {
+ WARNING("write_gcm plugin: Unable to determine scope of this instance.");
+ return;
+ }
+
+ if (strstr(scope, MONITORING_SCOPE) == NULL) {
+ size_t scope_len;
+
+ /* Strip trailing newline characers for printing. */
+ scope_len = strlen(scope);
+ while ((scope_len > 0) && (iscntrl((int)scope[scope_len - 1])))
+ scope[--scope_len] = 0;
+
+ WARNING("write_gcm plugin: The determined scope of this instance "
+ "(\"%s\") does not contain the monitoring scope (\"%s\"). You need "
+ "to add this scope to the list of scopes passed to gcutil with "
+ "--service_account_scopes when creating the instance. "
+ "Alternatively, to use this plugin on an instance which does not "
+ "have this scope, use a Service Account.",
+ scope, MONITORING_SCOPE);
+ }
+
+ sfree(scope);
+} /* }}} void wg_check_scope */
+
+static int wg_config_resource(oconfig_item_t *ci, wg_callback_t *cb) /* {{{ */
+{
+ if ((ci->values_num != 1) || (ci->values[0].type != OCONFIG_TYPE_STRING)) {
+ ERROR("write_gcm plugin: The \"%s\" option requires exactly one string "
+ "argument.",
+ ci->key);
+ return EINVAL;
+ }
+ char *resource_type = ci->values[0].value.string;
+
+ if (cb->resource != NULL) {
+ gcm_resource_destroy(cb->resource);
+ }
+
+ cb->resource = gcm_resource_create(resource_type);
+ if (cb->resource == NULL) {
+ ERROR("write_gcm plugin: gcm_resource_create(\"%s\") failed.",
+ resource_type);
+ return ENOMEM;
+ }
+
+ for (int i = 0; i < ci->children_num; i++) {
+ oconfig_item_t *child = ci->children + i;
+
+ if ((child->values_num != 1) ||
+ (child->values[0].type != OCONFIG_TYPE_STRING)) {
+ ERROR("write_gcm plugin: Resource labels must have exactly one string "
+ "value. Ignoring label \"%s\".",
+ child->key);
+ continue;
+ }
+
+ gcm_resource_add_label(cb->resource, child->key,
+ child->values[0].value.string);
+ }
+
+ return 0;
+} /* }}} int wg_config_resource */
+
+static int wg_config(oconfig_item_t *ci) /* {{{ */
+{
+ if (ci == NULL) {
+ return EINVAL;
+ }
+
+ wg_callback_t *cb = calloc(1, sizeof(*cb));
+ if (cb == NULL) {
+ ERROR("write_gcm plugin: calloc failed.");
+ return ENOMEM;
+ }
+ cb->url = strdup(GCM_API_URL);
+ pthread_mutex_init(&cb->lock, /* attr = */ NULL);
+
+ char *credential_file = NULL;
+
+ for (int i = 0; i < ci->children_num; i++) {
+ oconfig_item_t *child = ci->children + i;
+ if (strcasecmp("Project", child->key) == 0)
+ cf_util_get_string(child, &cb->project);
+ else if (strcasecmp("Email", child->key) == 0)
+ cf_util_get_string(child, &cb->email);
+ else if (strcasecmp("Url", child->key) == 0)
+ cf_util_get_string(child, &cb->url);
+ else if (strcasecmp("CredentialFile", child->key) == 0)
+ cf_util_get_string(child, &credential_file);
+ else if (strcasecmp("Resource", child->key) == 0)
+ wg_config_resource(child, cb);
+ else {
+ ERROR("write_gcm plugin: Invalid configuration option: %s.", child->key);
+ wg_callback_free(cb);
+ return EINVAL;
+ }
+ }
+
+ /* Set up authentication */
+ /* Option 1: Credentials file given => use service account */
+ if (credential_file != NULL) {
+ oauth_google_t cfg =
+ oauth_create_google_file(credential_file, MONITORING_SCOPE);
+ if (cfg.oauth == NULL) {
+ ERROR("write_gcm plugin: oauth_create_google_file failed");
+ wg_callback_free(cb);
+ return EINVAL;
+ }
+ cb->auth = cfg.oauth;
+
+ if (cb->project == NULL) {
+ cb->project = cfg.project_id;
+ INFO("write_gcm plugin: Automatically detected project ID: \"%s\"",
+ cb->project);
+ } else {
+ sfree(cfg.project_id);
+ }
+ }
+ /* Option 2: Look for credentials in well-known places */
+ if (cb->auth == NULL) {
+ oauth_google_t cfg = oauth_create_google_default(MONITORING_SCOPE);
+ cb->auth = cfg.oauth;
+
+ if (cb->project == NULL) {
+ cb->project = cfg.project_id;
+ INFO("write_gcm plugin: Automatically detected project ID: \"%s\"",
+ cb->project);
+ } else {
+ sfree(cfg.project_id);
+ }
+ }
+
+ if ((cb->auth != NULL) && (cb->email != NULL)) {
+ NOTICE("write_gcm plugin: A service account email was configured but is "
+ "not used for authentication because %s used instead.",
+ (credential_file != NULL) ? "a credential file was"
+ : "application default credentials were");
+ }
+
+ /* Option 3: Running on GCE => use metadata service */
+ if ((cb->auth == NULL) && gce_check()) {
+ wg_check_scope(cb->email);
+ } else if (cb->auth == NULL) {
+ ERROR("write_gcm plugin: Unable to determine credentials. Please either "
+ "specify the \"Credentials\" option or set up Application Default "
+ "Credentials.");
+ wg_callback_free(cb);
+ return EINVAL;
+ }
+
+ if ((cb->project == NULL) && gce_check()) {
+ cb->project = gce_project_id();
+ }
+ if (cb->project == NULL) {
+ ERROR("write_gcm plugin: Unable to determine the project number. "
+ "Please specify the \"Project\" option manually.");
+ wg_callback_free(cb);
+ return EINVAL;
+ }
+
+ if ((cb->resource == NULL) && gce_check()) {
+ /* TODO(octo): add error handling */
+ cb->resource = gcm_resource_create("gce_instance");
+ gcm_resource_add_label(cb->resource, "project_id", gce_project_id());
+ gcm_resource_add_label(cb->resource, "instance_id", gce_instance_id());
+ gcm_resource_add_label(cb->resource, "zone", gce_zone());
+ }
+ if (cb->resource == NULL) {
+ /* TODO(octo): add error handling */
+ cb->resource = gcm_resource_create("global");
+ gcm_resource_add_label(cb->resource, "project_id", cb->project);
+ }
+
+ DEBUG("write_gcm plugin: Registering write callback with URL %s", cb->url);
+ assert((cb->auth != NULL) || gce_check());
+
+ user_data_t user_data = {
+ .data = cb,
+ };
+ plugin_register_flush("write_gcm", wg_flush, &user_data);
+
+ user_data.free_func = wg_callback_free;
+ plugin_register_write("write_gcm", wg_write, &user_data);
+
+ return 0;
+} /* }}} int wg_config */
+
+static int wg_init(void) {
+ /* {{{ */
+ /* Call this while collectd is still single-threaded to avoid
+ * initialization issues in libgcrypt. */
+ curl_global_init(CURL_GLOBAL_SSL);
+
+ return 0;
+} /* }}} int wg_init */
+
+void module_register(void) /* {{{ */
+{
+ plugin_register_complex_config("write_gcm", wg_config);
+ plugin_register_init("write_gcm", wg_init);
+} /* }}} void module_register */
+
+/* vim: set sw=2 sts=2 et fdm=marker : */