MXS-1775 Introduce MonitorInstance::has_sufficient_permissions()

With this function in place, it is now possible to move the thread
starting to MonitorInstance.

include/maxscale/monitor.hh

@@ -32,6 +32,7 @@ public:
 protected:
     MonitorInstance(MXS_MONITOR* pMonitor);
 
+    virtual bool has_sufficient_permissions() const;
     virtual void configure(const MXS_CONFIG_PARAMETER* pParams);
 
     virtual void main() = 0;

server/core/monitor.cc

@@ -2535,6 +2535,11 @@ void MonitorInstance::stop()
     m_script = NULL;
 }
 
+bool MonitorInstance::has_sufficient_permissions() const
+{
+    return true;
+}
+
 void MonitorInstance::configure(const MXS_CONFIG_PARAMETER* pParams)
 {
 }

server/modules/monitor/auroramon/auroramon.cc

@@ -191,9 +191,7 @@ bool AuroraMonitor::start(const MXS_CONFIG_PARAMETER *params)
 
     if (!m_checked)
     {
-        if (!check_monitor_permissions(m_monitor, "SELECT @@aurora_server_id, server_id FROM "
+        if (!has_sufficient_permissions())
-                                       "information_schema.replica_host_status "
-                                       "WHERE session_id = 'MASTER_SESSION_ID'"))
         {
             MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
         }
@@ -222,6 +220,13 @@ bool AuroraMonitor::start(const MXS_CONFIG_PARAMETER *params)
     return started;
 }
 
+bool AuroraMonitor::has_sufficient_permissions() const
+{
+    return check_monitor_permissions(m_monitor, "SELECT @@aurora_server_id, server_id FROM "
+                                     "information_schema.replica_host_status "
+                                     "WHERE session_id = 'MASTER_SESSION_ID'");
+}
+
 void AuroraMonitor::configure(const MXS_CONFIG_PARAMETER* params)
 {
     m_script = config_copy_string(params, "script");

server/modules/monitor/auroramon/auroramon.hh

@@ -36,6 +36,7 @@ private:
     AuroraMonitor(MXS_MONITOR* monitor);
     ~AuroraMonitor();
 
+    bool has_sufficient_permissions() const;
     void configure(const MXS_CONFIG_PARAMETER* params);
 
     void main();

server/modules/monitor/galeramon/galeramon.cc

@@ -165,7 +165,7 @@ bool GaleraMonitor::start(const MXS_CONFIG_PARAMETER *params)
 
     if (!m_checked)
     {
-        if (!check_monitor_permissions(m_monitor, "SHOW STATUS LIKE 'wsrep_local_state'"))
+        if (!has_sufficient_permissions())
         {
             MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
         }
@@ -194,6 +194,11 @@ bool GaleraMonitor::start(const MXS_CONFIG_PARAMETER *params)
     return started;
 }
 
+bool GaleraMonitor::has_sufficient_permissions() const
+{
+    return check_monitor_permissions(m_monitor, "SHOW STATUS LIKE 'wsrep_local_state'");
+}
+
 void GaleraMonitor::configure(const MXS_CONFIG_PARAMETER* params)
 {
     m_disableMasterFailback = config_get_bool(params, "disable_master_failback");

server/modules/monitor/galeramon/galeramon.hh

@@ -81,8 +81,6 @@ private:
     GaleraMonitor(MXS_MONITOR* monitor);
     ~GaleraMonitor();
 
-    void configure(const MXS_CONFIG_PARAMETER* param);
-
     bool detect_cluster_size(const int n_nodes,
                              const char *candidate_uuid,
                              const int candidate_size);
@@ -93,5 +91,8 @@ private:
     void set_galera_cluster();
     void update_sst_donor_nodes(int is_cluster);
 
+    bool has_sufficient_permissions() const;
+    void configure(const MXS_CONFIG_PARAMETER* param);
+
     void main();
 };

server/modules/monitor/grmon/grmon.cc

@@ -56,7 +56,14 @@ bool GRMon::start(const MXS_CONFIG_PARAMETER* params)
 
     if (!m_checked)
     {
-        m_checked = true;
+        if (!has_sufficient_permissions())
+        {
+            MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
+        }
+        else
+        {
+            m_checked = true;
+        }
     }
 
     if (m_checked)
@@ -76,6 +83,11 @@ bool GRMon::start(const MXS_CONFIG_PARAMETER* params)
     return started;
 }
 
+bool GRMon::has_sufficient_permissions() const
+{
+    return true;
+}
+
 void GRMon::configure(const MXS_CONFIG_PARAMETER* params)
 {
     m_script = config_get_string(params, "script");

server/modules/monitor/grmon/grmon.hh

@@ -39,6 +39,7 @@ private:
     GRMon(MXS_MONITOR* monitor);
     ~GRMon();
 
+    bool has_sufficient_permissions() const;
     void configure(const MXS_CONFIG_PARAMETER* params);
 
     void main();

server/modules/monitor/mmmon/mmmon.cc

@@ -127,7 +127,7 @@ bool MMMonitor::start(const MXS_CONFIG_PARAMETER *params)
 
     if (!m_checked)
     {
-        if (!check_monitor_permissions(m_monitor, "SHOW SLAVE STATUS"))
+        if (!has_sufficient_permissions())
         {
             MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
         }
@@ -156,6 +156,11 @@ bool MMMonitor::start(const MXS_CONFIG_PARAMETER *params)
     return started;
 }
 
+bool MMMonitor::has_sufficient_permissions() const
+{
+    return check_monitor_permissions(m_monitor, "SHOW SLAVE STATUS");
+}
+
 void MMMonitor::configure(const MXS_CONFIG_PARAMETER* params)
 {
     m_script = config_copy_string(params, "script");

server/modules/monitor/mmmon/mmmon.hh

@@ -42,6 +42,7 @@ private:
 
     MXS_MONITORED_SERVER *get_current_master();
 
+    bool has_sufficient_permissions() const;
     void configure(const MXS_CONFIG_PARAMETER* params);
 
     void main();

server/modules/monitor/ndbclustermon/ndbclustermon.cc

@@ -111,7 +111,7 @@ bool NDBCMonitor::start(const MXS_CONFIG_PARAMETER *params)
 
     if (!m_checked)
     {
-        if (!check_monitor_permissions(m_monitor, "SHOW STATUS LIKE 'Ndb_number_of_ready_data_nodes'"))
+        if (!has_sufficient_permissions())
         {
             MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
         }
@@ -140,6 +140,11 @@ bool NDBCMonitor::start(const MXS_CONFIG_PARAMETER *params)
     return started;
 }
 
+bool NDBCMonitor::has_sufficient_permissions() const
+{
+    return check_monitor_permissions(m_monitor, "SHOW STATUS LIKE 'Ndb_number_of_ready_data_nodes'");
+}
+
 void NDBCMonitor::configure(const MXS_CONFIG_PARAMETER* params)
 {
     m_script = config_copy_string(params, "script");

server/modules/monitor/ndbclustermon/ndbclustermon.hh

@@ -39,6 +39,7 @@ private:
     NDBCMonitor(MXS_MONITOR* monitor);
     ~NDBCMonitor();
 
+    bool has_sufficient_permissions() const;
     void configure(const MXS_CONFIG_PARAMETER* params);
 
     void main();