add support to anonymize internal tags

Author: shaan420

m3/config.go

@@ -50,9 +50,14 @@ type Configuration struct {
 	// with the histogram bucket bound values.
 	HistogramBucketTagPrecision uint `yaml:"histogramBucketTagPrecision"`
 
-	// CommonTagsInternal are tags that should be added to all internal metrics
+	// InternalTags are tags that should be added to all internal metrics
 	// emitted by the reporter.
-	CommonTagsInternal map[string]string `yaml:"commonTagsInternal"`
+	InternalTags map[string]string `yaml:"internalTags"`
+
+	// InternalTagsToAnonymize are tags that should be anonymized in all internal
+	// metrics emitted by the reporter. The values of these tags will be replaced
+	// with the string "global".
+	InternalTagsToAnonymize []string `yaml:"internalTagsToAnonymize"`
 }
 
 // NewReporter creates a new M3 reporter from this configuration.
@@ -70,6 +75,7 @@ func (c Configuration) NewReporter() (Reporter, error) {
 		MaxPacketSizeBytes:          c.PacketSize,
 		IncludeHost:                 c.IncludeHost,
 		HistogramBucketTagPrecision: c.HistogramBucketTagPrecision,
-		InternalTags:                c.CommonTagsInternal,
+		InternalTags:                c.InternalTags,
+		InternalTagsToAnonymize:     c.InternalTagsToAnonymize,
 	})
 }

m3/config_test.go

@@ -42,7 +42,7 @@ func TestConfigSimple(t *testing.T) {
 	assert.True(t, ok)
 	assert.True(t, tagEquals(reporter.commonTags, "service", "my-service"))
 	assert.True(t, tagEquals(reporter.commonTags, "env", "test"))
-	assert.Equal(t, 0, len(c.CommonTagsInternal))
+	assert.Equal(t, 0, len(c.InternalTags))
 }
 
 func TestConfigMulti(t *testing.T) {

m3/reporter.go

@@ -150,6 +150,7 @@ type Options struct {
 	HistogramBucketName         string
 	HistogramBucketTagPrecision uint
 	InternalTags                map[string]string
+	InternalTagsToAnonymize     []string
 }
 
 // NewReporter creates a new M3 reporter.
@@ -294,6 +295,11 @@ func NewReporter(opts Options) (Reporter, error) {
 		internalTags[k] = v
 	}
 
+	for _, toAnonomize := range opts.InternalTagsToAnonymize {
+		// override if present, set if not.
+		internalTags[toAnonomize] = "global"
+	}
+
 	r.batchSizeHistogram = r.AllocateHistogram("tally.internal.batch-size", internalTags, buckets)
 	r.numBatchesCounter = r.AllocateCounter("tally.internal.num-batches", internalTags)
 	r.numMetricsCounter = r.AllocateCounter("tally.internal.num-metrics", internalTags)

m3/reporter_test.go

@@ -580,6 +580,10 @@ func TestReporterCommmonTagsInternal(t *testing.T) {
 		IncludeHost:        true,
 		MaxPacketSizeBytes: maxPacketSize,
 		InternalTags:       internalTags,
+		InternalTagsToAnonymize: []string{
+			"host",
+			"instance",
+		},
 	})
 	require.NoError(t, err)
 	defer r.Close()
@@ -598,17 +602,19 @@ func TestReporterCommmonTagsInternal(t *testing.T) {
 			numInternalMetricsActual++
 			for k, v := range internalTags {
 				require.True(t, tagEquals(metric.Tags, k, v))
+				require.True(t, tagEquals(metric.Tags, "host", "global"))
+				require.True(t, tagEquals(metric.Tags, "instance", "global"))
 			}
 		} else {
 			require.Equal(t, "testCounter1", metric.Name)
 			require.False(t, tagIncluded(metric.Tags, "internal1"))
 			require.False(t, tagIncluded(metric.Tags, "internal2"))
+			// The following tags should not be present as part of the individual metrics
+			// as they are common tags.
+			require.False(t, tagIncluded(metric.Tags, "host"))
+			require.False(t, tagIncluded(metric.Tags, "instance"))
+			require.False(t, tagIncluded(metric.Tags, "service"))
 		}
-		// The following tags should not be present as part of the individual metrics
-		// as they are common tags.
-		require.False(t, tagIncluded(metric.Tags, "host"))
-		require.False(t, tagIncluded(metric.Tags, "instance"))
-		require.False(t, tagIncluded(metric.Tags, "service"))
 	}
 	require.Equal(t, internalMetrics, numInternalMetricsActual)
 }