root/daemons/attrd/attrd_alerts.c

/* */

DEFINITIONS

1. attrd_lrmd_callback
2. attrd_lrmd_connect
3. attrd_lrmd_disconnect
4. config_query_callback
5. attrd_read_options
6. attrd_send_attribute_alert

   1 /*
   2  * Copyright 2015-2023 the Pacemaker project contributors
   3  *
   4  * The version control history for this file may have further details.
   5  *
   6  * This source code is licensed under the GNU General Public License version 2
   7  * or later (GPLv2+) WITHOUT ANY WARRANTY.
   8  */
   9 
  10 #include <crm_internal.h>
  11 #include <crm/crm.h>
  12 #include <crm/cib/internal.h>
  13 #include <crm/msg_xml.h>
  14 #include <crm/cluster/internal.h>
  15 #include <crm/cluster/election_internal.h>
  16 #include <crm/common/alerts_internal.h>
  17 #include <crm/common/cib_internal.h>
  18 #include <crm/pengine/rules_internal.h>
  19 #include <crm/lrmd_internal.h>
  20 #include "pacemaker-attrd.h"
  21 
  22 static GList *attrd_alert_list = NULL;
  23 
  24 static void
  25 attrd_lrmd_callback(lrmd_event_data_t * op)
     /*  */
  26 {
  27     CRM_CHECK(op != NULL, return);
  28     switch (op->type) {
  29         case lrmd_event_disconnect:
  30             crm_info("Lost connection to executor");
  31             attrd_lrmd_disconnect();
  32             break;
  33         default:
  34             break;
  35     }
  36 }
  37 
  38 static lrmd_t *
  39 attrd_lrmd_connect(void)
     /*  */
  40 {
  41     if (the_lrmd == NULL) {
  42         the_lrmd = lrmd_api_new();
  43         the_lrmd->cmds->set_callback(the_lrmd, attrd_lrmd_callback);
  44     }
  45 
  46     if (!the_lrmd->cmds->is_connected(the_lrmd)) {
  47         const unsigned int max_attempts = 10;
  48         int ret = -ENOTCONN;
  49 
  50         for (int fails = 0; fails < max_attempts; ++fails) {
  51             ret = the_lrmd->cmds->connect(the_lrmd, T_ATTRD, NULL);
  52             if (ret == pcmk_ok) {
  53                 break;
  54             }
  55 
  56             crm_debug("Could not connect to executor, %d tries remaining",
  57                       (max_attempts - fails));
  58             /* @TODO We don't want to block here with sleep, but we should wait
  59              * some time between connection attempts. We could possibly add a
  60              * timer with a callback, but then we'd likely need an alert queue.
  61              */
  62         }
  63 
  64         if (ret != pcmk_ok) {
  65             attrd_lrmd_disconnect();
  66         }
  67     }
  68 
  69     return the_lrmd;
  70 }
  71 
  72 void
  73 attrd_lrmd_disconnect(void) {
     /*  */
  74     if (the_lrmd) {
  75         lrmd_t *conn = the_lrmd;
  76 
  77         the_lrmd = NULL; /* in case we're called recursively */
  78         lrmd_api_delete(conn); /* will disconnect if necessary */
  79     }
  80 }
  81 
  82 static void
  83 config_query_callback(xmlNode * msg, int call_id, int rc, xmlNode * output, void *user_data)
     /*  */
  84 {
  85     xmlNode *crmalerts = NULL;
  86 
  87     if (rc == -ENXIO) {
  88         crm_debug("Local CIB has no alerts section");
  89         return;
  90     } else if (rc != pcmk_ok) {
  91         crm_notice("Could not query local CIB: %s", pcmk_strerror(rc));
  92         return;
  93     }
  94 
  95     crmalerts = output;
  96     if ((crmalerts != NULL) && !pcmk__xe_is(crmalerts, XML_CIB_TAG_ALERTS)) {
  97         crmalerts = first_named_child(crmalerts, XML_CIB_TAG_ALERTS);
  98     }
  99     if (!crmalerts) {
 100         crm_notice("CIB query result has no " XML_CIB_TAG_ALERTS " section");
 101         return;
 102     }
 103 
 104     pe_free_alert_list(attrd_alert_list);
 105     attrd_alert_list = pe_unpack_alerts(crmalerts);
 106 }
 107 
 108 gboolean
 109 attrd_read_options(gpointer user_data)
     /*  */
 110 {
 111     int call_id;
 112 
 113     CRM_CHECK(the_cib != NULL, return TRUE);
 114 
 115     call_id = the_cib->cmds->query(the_cib,
 116                                    pcmk__cib_abs_xpath_for(XML_CIB_TAG_ALERTS),
 117                                    NULL, cib_xpath|cib_scope_local);
 118 
 119     the_cib->cmds->register_callback_full(the_cib, call_id, 120, FALSE, NULL,
 120                                           "config_query_callback",
 121                                           config_query_callback, free);
 122 
 123     crm_trace("Querying the CIB... call %d", call_id);
 124     return TRUE;
 125 }
 126 
 127 int
 128 attrd_send_attribute_alert(const char *node, int nodeid,
     /*  */
 129                            const char *attr, const char *value)
 130 {
 131     if (attrd_alert_list == NULL) {
 132         return pcmk_ok;
 133     }
 134     return lrmd_send_attribute_alert(attrd_lrmd_connect(), attrd_alert_list,
 135                                      node, nodeid, attr, value);
 136 }

/* */