Complete diagnostics support

monitor/go_runtime.go

@@ -31,7 +31,13 @@ func (g *goRuntime) Statistics() (map[string]interface{}, error) {
 	}, nil
 }
 
-// Diagnostics returns the statistics for the goRuntime type
-func (g *goRuntime) Diagnostics() (map[string]interface{}, error) {
-	return nil, nil
+func (g *goRuntime) Diagnostics() (*Diagnostic, error) {
+	diagnostics := map[string]interface{}{
+		"GOARCH":     runtime.GOARCH,
+		"GOOS":       runtime.GOOS,
+		"GOMAXPROCS": runtime.GOMAXPROCS(-1),
+		"version":    runtime.Version(),
+	}
+
+	return DiagnosticFromMap(diagnostics), nil
 }

monitor/network.go

@@ -0,0 +1,26 @@
+package monitor
+
+import (
+	"os"
+)
+
+// network captures network statistics and implements the monitor client interface
+type network struct{}
+
+// Statistics returns the statistics for the network type
+func (n *network) Statistics() (map[string]interface{}, error) {
+	return nil, nil
+}
+
+func (n *network) Diagnostics() (*Diagnostic, error) {
+	h, err := os.Hostname()
+	if err != nil {
+		return nil, err
+	}
+
+	diagnostics := map[string]interface{}{
+		"hostname": h,
+	}
+
+	return DiagnosticFromMap(diagnostics), nil
+}

monitor/service.go

@@ -11,22 +11,64 @@ import (
 
 	"github.com/influxdb/influxdb/cluster"
 	"github.com/influxdb/influxdb/meta"
+	"github.com/influxdb/influxdb/tsdb"
 )
 
 const leaderWaitTimeout = 30 * time.Second
 
-// Client is the interface modules must implement if they wish to register with monitor.
-type Client interface {
+// StatsClient is the interface modules must implement if they wish to register with monitor.
+type StatsClient interface {
+	// Statistics returns a map of keys to values. Each Value must be either int64 or float64.
+	// Statistical information is written to an InfluxDB system if enabled.
 	Statistics() (map[string]interface{}, error)
-	Diagnostics() (map[string]interface{}, error)
+}
+
+// DiagsClient is the interface modules implement if they register diags with monitor.
+type DiagsClient interface {
+	Diagnostics() (*Diagnostic, error)
+}
+
+// The DiagsClientFunc type is an adapter to allow the use of
+// ordinary functions as Diagnostis clients.
+type DiagsClientFunc func() (*Diagnostic, error)
+
+// Diagnostics calls f().
+func (f DiagsClientFunc) Diagnostics() (*Diagnostic, error) {
+	return f()
+}
+
+// Diagnostic represents a table of diagnostic information. The first value
+// is the name of the columns, the second is a slice of interface slices containing
+// the values for each column, by row. This information is never written to an InfluxDB
+// system and is display-only. An example showing, say, connections follows:
+//
+//     source_ip    source_port       dest_ip     dest_port
+//     182.1.0.2    2890              127.0.0.1   38901
+//     174.33.1.2   2924              127.0.0.1   38902
+type Diagnostic struct {
+	Columns []string
+	Rows    [][]interface{}
+}
+
+func NewDiagnostic(columns []string) *Diagnostic {
+	return &Diagnostic{
+		Columns: columns,
+		Rows:    make([][]interface{}, 0),
+	}
+}
+
+func (d *Diagnostic) AddRow(r []interface{}) {
+	d.Rows = append(d.Rows, r)
 }
 
 // Monitor represents an instance of the monitor system.
 type Monitor struct {
-	wg            sync.WaitGroup
-	done          chan struct{}
-	mu            sync.Mutex
-	registrations []*clientWithMeta
+	wg   sync.WaitGroup
+	done chan struct{}
+	mu   sync.Mutex
+
+	statRegistrations []*clientWithMeta
+	diagRegistrations map[string]DiagsClient
 
 	storeEnabled  bool
 	storeDatabase string
@@ -50,12 +92,13 @@ type Monitor struct {
 // New returns a new instance of the monitor system.
 func New(c Config) *Monitor {
 	return &Monitor{
-		done:          make(chan struct{}),
-		registrations: make([]*clientWithMeta, 0),
-		storeEnabled:  c.StoreEnabled,
-		storeDatabase: c.StoreDatabase,
-		storeInterval: time.Duration(c.StoreInterval),
-		Logger:        log.New(os.Stderr, "[monitor] ", log.LstdFlags),
+		done:              make(chan struct{}),
+		statRegistrations: make([]*clientWithMeta, 0),
+		diagRegistrations: make(map[string]DiagsClient),
+		storeEnabled:      c.StoreEnabled,
+		storeDatabase:     c.StoreDatabase,
+		storeInterval:     time.Duration(c.StoreInterval),
+		Logger:            log.New(os.Stderr, "[monitor] ", log.LstdFlags),
 	}
 }
 
@@ -64,8 +107,12 @@ func New(c Config) *Monitor {
 func (m *Monitor) Open() error {
 	m.Logger.Printf("Starting monitor system")
 
-	// Self-register Go runtime statm.
-	m.Register("runtime", nil, &goRuntime{})
+	// Self-register various stats and diagnostics.
+	gr := &goRuntime{}
+	m.RegisterStatsClient("runtime", nil, gr)
+	m.RegisterDiagnosticsClient("runtime", gr)
+	m.RegisterDiagnosticsClient("network", &network{})
+	m.RegisterDiagnosticsClient("system", &system{})
 
 	// If enabled, record stats in a InfluxDB system.
 	if m.storeEnabled {
@@ -92,16 +139,49 @@ func (m *Monitor) SetLogger(l *log.Logger) {
 }
 
 // Register registers a client with the given name and tags.
-func (m *Monitor) Register(name string, tags map[string]string, client Client) error {
+func (m *Monitor) RegisterStatsClient(name string, tags map[string]string, client StatsClient) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
+
+	a := tags
+	if a == nil {
+		a = make(map[string]string)
+	}
+
+	// Get cluster-level metadata to supplement stats.
+	var clusterID string
+	var hostname string
+	var err error
+	if cID, err := m.MetaStore.ClusterID(); err != nil {
+		m.Logger.Printf("failed to determine cluster ID: %s", err)
+	} else {
+		clusterID = strconv.FormatUint(cID, 10)
+	}
+	nodeID := strconv.FormatUint(m.MetaStore.NodeID(), 10)
+	if hostname, err = os.Hostname(); err != nil {
+		m.Logger.Printf("failed to determine hostname: %s", err)
+	}
+	a["clusterID"] = clusterID
+	a["nodeID"] = nodeID
+	a["hostname"] = hostname
+
 	c := &clientWithMeta{
-		Client: client,
-		name:   name,
-		tags:   tags,
+		StatsClient: client,
+		name:        name,
+		tags:        a,
 	}
-	m.registrations = append(m.registrations, c)
-	m.Logger.Printf(`'%s:%v' registered for monitoring`, name, tags)
+
+	m.statRegistrations = append(m.statRegistrations, c)
+	m.Logger.Printf(`'%s:%v' registered for statistics monitoring`, name, tags)
+	return nil
+}
+
+// RegisterDiagnosticsClient registers a diagnostics client with the given name and tags.
+func (m *Monitor) RegisterDiagnosticsClient(name string, client DiagsClient) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.diagRegistrations[name] = client
+	m.Logger.Printf(`'%s' registered for diagnostics monitoring`, name)
 	return nil
 }
 
@@ -110,9 +190,9 @@ func (m *Monitor) Statistics() ([]*statistic, error) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 
-	statistics := make([]*statistic, 0, len(m.registrations))
-	for _, r := range m.registrations {
-		stats, err := r.Client.Statistics()
+	statistics := make([]*statistic, 0, len(m.statRegistrations))
+	for _, r := range m.statRegistrations {
+		stats, err := r.StatsClient.Statistics()
 		if err != nil {
 			continue
 		}
@@ -127,14 +207,24 @@ func (m *Monitor) Statistics() ([]*statistic, error) {
 	return statistics, nil
 }
 
+func (m *Monitor) Diagnostics() (map[string]*Diagnostic, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	diags := make(map[string]*Diagnostic, len(m.diagRegistrations))
+	for k, v := range m.diagRegistrations {
+		d, err := v.Diagnostics()
+		if err != nil {
+			continue
+		}
+		diags[k] = d
+	}
+	return diags, nil
+}
+
 // storeStatistics writes the statistics to an InfluxDB system.
 func (m *Monitor) storeStatistics() {
-	// XXX add tags such as local hostname and cluster ID
-	//a.Tags["clusterID"] = strconv.FormatUint(m.clusterID, 10)
-	//a.Tags["nodeID"] = strconv.FormatUint(m.nodeID, 10)
-	//a.Tags["hostname"] = m.hostname
 	defer m.wg.Done()
-
 	m.Logger.Printf("storing statistics in database '%s', interval %s",
 		m.storeDatabase, m.storeInterval)
 
@@ -154,7 +244,26 @@ func (m *Monitor) storeStatistics() {
 	for {
 		select {
 		case <-tick.C:
-			// Write stats here.
+			stats, err := m.Statistics()
+			if err != nil {
+				m.Logger.Printf("failed to retrieve registered statistics: %s", err)
+				continue
+			}
+
+			points := make(tsdb.Points, 0, len(stats))
+			for _, s := range stats {
+				points = append(points, tsdb.NewPoint(s.Name, s.Tags, s.Values, time.Now()))
+			}
+
+			err = m.PointsWriter.WritePoints(&cluster.WritePointsRequest{
+				Database:         m.storeDatabase,
+				RetentionPolicy:  "",
+				ConsistencyLevel: cluster.ConsistencyLevelOne,
+				Points:           points,
+			})
+			if err != nil {
+				m.Logger.Printf("failed to store statistics: %s", err)
+			}
 		case <-m.done:
 			m.Logger.Printf("terminating storage of statistics")
 			return
@@ -170,16 +279,11 @@ type statistic struct {
 	Values map[string]interface{}
 }
 
-// newStatistic returns a new statistic object. It ensures that tags are always non-nil.
+// newStatistic returns a new statistic object.
 func newStatistic(name string, tags map[string]string, values map[string]interface{}) *statistic {
-	a := tags
-	if a == nil {
-		a = make(map[string]string)
-	}
-
 	return &statistic{
 		Name:   name,
-		Tags:   a,
+		Tags:   tags,
 		Values: values,
 	}
 }
@@ -206,24 +310,24 @@ func (s *statistic) valueNames() []string {
 
 // clientWithMeta wraps a registered client with its associated name and tagm.
 type clientWithMeta struct {
-	Client
+	StatsClient
 	name string
 	tags map[string]string
 }
 
-// MonitorClient wraps a *expvar.Map so that it implements the Client interface. It is for
-// use by external packages that just record stats in an expvar.Map type.
-type MonitorClient struct {
+// StatsMonitorClient wraps a *expvar.Map so that it implements the StatsClient interface.
+// It is for use by external packages that just record stats in an expvar.Map type.
+type StatsMonitorClient struct {
 	ep *expvar.Map
 }
 
-// NewMonitorClient returns a new MonitorClient using the given expvar.Map.
-func NewMonitorClient(ep *expvar.Map) *MonitorClient {
-	return &MonitorClient{ep: ep}
+// NewStatsMonitorClient returns a new StatsMonitorClient using the given expvar.Map.
+func NewStatsMonitorClient(ep *expvar.Map) *StatsMonitorClient {
+	return &StatsMonitorClient{ep: ep}
 }
 
-// Statistics implements the Client interface for a MonitorClient.
-func (m MonitorClient) Statistics() (map[string]interface{}, error) {
+// Statistics implements the Client interface for a StatsMonitorClient.
+func (m StatsMonitorClient) Statistics() (map[string]interface{}, error) {
 	values := make(map[string]interface{})
 	m.ep.Do(func(kv expvar.KeyValue) {
 		var f interface{}
@@ -248,7 +352,21 @@ func (m MonitorClient) Statistics() (map[string]interface{}, error) {
 	return values, nil
 }
 
-// Diagnostics implements the Client interface for a MonitorClient.
-func (m MonitorClient) Diagnostics() (map[string]interface{}, error) {
-	return nil, nil
+// DiagnosticFromMap returns a Diagnostic from a map.
+func DiagnosticFromMap(m map[string]interface{}) *Diagnostic {
+	// Display columns in deterministic order.
+	sortedKeys := make([]string, 0, len(m))
+	for k, _ := range m {
+		sortedKeys = append(sortedKeys, k)
+	}
+	sort.Strings(sortedKeys)
+
+	d := NewDiagnostic(sortedKeys)
+	row := make([]interface{}, len(sortedKeys))
+	for i, k := range sortedKeys {
+		row[i] = m[k]
+	}
+	d.AddRow(row)
+
+	return d
 }

monitor/service_test.go

@@ -24,21 +24,24 @@ func Test_RegisterStats(t *testing.T) {
 	}
 
 	// Register a client without tags.
-	if err := monitor.Register("foo", nil, client); err != nil {
+	if err := monitor.RegisterStatsClient("foo", nil, client); err != nil {
 		t.Fatalf("failed to register client: %s", err.Error())
 	}
 	json := executeShowStatsJSON(t, executor)
-	if !strings.Contains(json, `{"name":"foo","columns":["bar","qux"],"values":[[1,2.4]]}]}`) {
+	if !strings.Contains(json, `"columns":["bar","qux"],"values":[[1,2.4]]`) || !strings.Contains(json, `"name":"foo"`) {
 		t.Fatalf("SHOW STATS response incorrect, got: %s\n", json)
 	}
 
 	// Register a client with tags.
-	if err := monitor.Register("baz", map[string]string{"proto": "tcp"}, client); err != nil {
+	if err := monitor.RegisterStatsClient("baz", map[string]string{"proto": "tcp"}, client); err != nil {
 		t.Fatalf("failed to register client: %s", err.Error())
 	}
 	json = executeShowStatsJSON(t, executor)
-	if !strings.Contains(json, `{"name":"baz","tags":{"proto":"tcp"},"columns":["bar","qux"],"values":[[1,2.4]]}]}`) {
+	if !strings.Contains(json, `"columns":["bar","qux"],"values":[[1,2.4]]`) ||
+		!strings.Contains(json, `"name":"baz"`) ||
+		!strings.Contains(json, `"proto":"tcp"`) {
 		t.Fatalf("SHOW STATS response incorrect, got: %s\n", json)
+
 	}
 }