Metrics2: Store a registry of Counters

go/metrics2/metrics.go

Index: go/metrics2/metrics.go
diff --git a/go/metrics2/metrics.go b/go/metrics2/metrics.go
index 1636283923d60f4aeb36f43af48414c6cd62f4f6..7302be3872f8071e07d5f0c5f0a986b26c4bbe78 100644
--- a/go/metrics2/metrics.go
+++ b/go/metrics2/metrics.go
@@ -23,6 +23,7 @@ const (
 var (
 	DefaultClient *Client = &Client{
 		aggMetrics: map[string]*aggregateMetric{},
+		counters:   map[string]*Counter{},
 		metrics:    map[string]*rawMetric{},
 	}
 )
@@ -44,6 +45,7 @@ func Init(appName string, influxClient *influxdb.Client) error {
 	// Some metrics may already be registered with DefaultClient. Copy them
 	// over.
 	c.aggMetrics = DefaultClient.aggMetrics
+	c.counters = DefaultClient.counters
 	c.metrics = DefaultClient.metrics
 
 	// Set the default client.
@@ -53,12 +55,18 @@ func Init(appName string, influxClient *influxdb.Client) error {
 
 // Client is a struct used for communicating with an InfluxDB instance.
 type Client struct {
-	aggMetrics      map[string]*aggregateMetric
-	aggMetricsMtx   sync.Mutex
-	influxClient    *influxdb.Client
-	defaultTags     map[string]string
-	metrics         map[string]*rawMetric
-	metricsMtx      sync.Mutex
+	aggMetrics    map[string]*aggregateMetric
+	aggMetricsMtx sync.Mutex
+
+	counters    map[string]*Counter
+	countersMtx sync.Mutex
+
+	influxClient *influxdb.Client
+	defaultTags  map[string]string
+
+	metrics    map[string]*rawMetric
+	metricsMtx sync.Mutex
+
 	reportFrequency time.Duration
 	values          *influxdb.BatchPoints
 	valuesMtx       sync.Mutex
@@ -76,6 +84,8 @@ func NewClient(influxClient *influxdb.Client, defaultTags map[string]string, rep
 	c := &Client{
 		aggMetrics:      map[string]*aggregateMetric{},
 		aggMetricsMtx:   sync.Mutex{},
+		counters:        map[string]*Counter{},
+		countersMtx:     sync.Mutex{},
 		influxClient:    influxClient,
 		defaultTags:     defaultTags,
 		metrics:         map[string]*rawMetric{},
@@ -264,3 +274,29 @@ func (c *Client) getAggregateMetric(measurement string, tagsList []map[string]st
 	}
 	return m
 }
+
+// getCounter creates or retrieves a Counter with the given name and tag set and

[stephana, 2016/02/24 14:48:16]

This should be in counter.go file, all the other GetX(...) functions are the
packages where their main logic is. 

[borenet, 2016/02/24 15:09:35]

Done.

+// returns it.
+func (c *Client) GetCounter(name string, tagsList ...map[string]string) *Counter {
+	c.countersMtx.Lock()
+	defer c.countersMtx.Unlock()
+
+	// Make a copy of the concatenation of all provided tags.
+	tags := util.AddParams(map[string]string{}, tagsList...)
+	tags["name"] = name
+	md5, err := util.MD5Params(tags)
+	if err != nil {
+		glog.Errorf("Failed to encode measurement tags: %s", err)
+	}
+	key := fmt.Sprintf("%s_%s", MEASUREMENT_COUNTER, md5)
+	m, ok := c.counters[key]
+	if !ok {
+		m = &Counter{
+			m:   c.GetInt64Metric(MEASUREMENT_COUNTER, tags),
+			mtx: sync.Mutex{},

[stephana, 2016/02/24 14:48:16]

nit: Mutex doesn't need to be initialized, it's unlocked by default. 

[borenet, 2016/02/24 15:09:35]

Done, here and elsewhere.

+		}
+		c.counters[key] = m
+	}
+	return m
+
+}