Feat[mqb]: Add broker stats to stat log

This commit adds the # of clients and queues to the broker's stat log.
These values can be derived from existing stats with some legwork;
logging them in one line just makes it easier.

Note: These metrics show the number of connected clients and opened
queues. If a queue exists in storage but has no clients, it does not
count.

Signed-off-by: Christopher Beard <[email protected]>

Author: chrisbeard

src/groups/mqb/mqbstat/mqbstat_brokerstats.cpp

@@ -115,7 +115,6 @@ BrokerStatsUtil::initializeStatContext(int               historySize,
     config.isTable(true)
         .defaultHistorySize(historySize)
         .statValueAllocator(allocator)
-        .storeExpiredSubcontextValues(true)
         .value("queue_count")
         .value("client_count");
 
@@ -129,5 +128,41 @@ BrokerStatsUtil::initializeStatContext(int               historySize,
     return statContext;
 }
 
+void BrokerStatsUtil::initializeTableAndTipBroker(
+    bmqst::Table*                  table,
+    bmqst::BasicTableInfoProvider* tip,
+    int                            historySize,
+    bmqst::StatContext*            statContext)
+{
+    // Use only one level for now ...
+    bmqst::StatValue::SnapshotLocation start(0, 0);
+    bmqst::StatValue::SnapshotLocation end(0, historySize - 1);
+
+    // Create table
+    bmqst::TableSchema& schema = table->schema();
+
+    schema.addDefaultIdColumn("id");
+    schema.addColumn("clients",
+                     BrokerStats::Stat::e_CLIENT_COUNT,
+                     bmqst::StatUtil::value,
+                     start);
+    schema.addColumn("queues",
+                     BrokerStats::Stat::e_QUEUE_COUNT,
+                     bmqst::StatUtil::value,
+                     start);
+
+    // Configure records
+    bmqst::TableRecords& records = table->records();
+    records.setContext(statContext);
+
+    // Create the tip
+    tip->setTable(table);
+    tip->setColumnGroup("");
+    tip->addColumn("id", "").justifyLeft();
+    tip->addColumn("clients", "# clients").zeroString("");
+    tip->addColumn("queues", "# queues").zeroString("");
+
+}
+
 }  // close package namespace
 }  // close enterprise namespace

src/groups/mqb/mqbstat/mqbstat_brokerstats.h

@@ -30,10 +30,13 @@
 // MQB
 
 // BMQ
+#include <bmqst_basictableinfoprovider.h>
 #include <bmqst_statcontext.h>
+#include <bmqst_table.h>
 #include <bmqt_uri.h>
 
 // BDE
+#include <ball_log.h>
 #include <bsl_memory.h>
 #include <bsl_string.h>
 #include <bslma_allocator.h>
@@ -151,6 +154,14 @@ struct BrokerStatsUtil {
     /// specified `allocator` for all stat context and stat values.
     static bsl::shared_ptr<bmqst::StatContext>
     initializeStatContext(int historySize, bslma::Allocator* allocator);
+
+    /// Load in the specified `table` and `tip` the objects to print the
+    /// specified `statContext` for the specified `historySize`.
+    static void
+    initializeTableAndTipBroker(bmqst::Table*                  table,
+                                bmqst::BasicTableInfoProvider* tip,
+                                int                            historySize,
+                                bmqst::StatContext*            statContext);
 };
 
 // ============================================================================

src/groups/mqb/mqbstat/mqbstat_printer.cpp

@@ -18,6 +18,7 @@
 
 #include <mqbscm_version.h>
 // MQB
+#include <mqbstat_brokerstats.h>
 #include <mqbstat_queuestats.h>
 
 #include <bmqio_statchannelfactory.h>
@@ -90,6 +91,12 @@ void Printer::initializeTablesAndTips()
                                                  historySize,
                                                  context->d_statContext_p);
 
+    context = d_contexts["broker"].get();
+    BrokerStatsUtil::initializeTableAndTipBroker(&context->d_table,
+                                                 &context->d_tip,
+                                                 historySize,
+                                                 context->d_statContext_p);
+
     context = d_contexts["clients"].get();
     QueueStatsUtil::initializeTableAndTipClients(&context->d_table,
                                                  &context->d_tip,
@@ -214,11 +221,19 @@ void Printer::stop()
 void Printer::printStats(bsl::ostream& stream)
 {
     // This must execute in the 'snapshot' thread
+    Context* context;
+
+    // BROKER
+    stream << "\n"
+           << ":::::::::: :::::::::: BROKER >>";
+    context = d_contexts["broker"].get();
+    context->d_table.records().update();
+    bmqst::TableUtil::printTable(stream, context->d_tip);
 
     // DOMAINQUEUES
     stream << "\n"
            << ":::::::::: :::::::::: DOMAINQUEUES >>";
-    Context* context = d_contexts["domainQueues"].get();
+    context = d_contexts["domainQueues"].get();
     context->d_table.records().update();
     bmqst::TableUtil::printTable(stream, context->d_tip);