Bug 1176992 - Allow hud.js to support custom metrics with exponential and counter histograms. r=janx

b2g/chrome/content/devtools/hud.js

@@ -366,18 +366,33 @@ Target.prototype = {
     } else {
       let histogramName = CUSTOM_HISTOGRAM_PREFIX + metricAppName + '_'
         + metricName;
-      if (!developerHUD._customHistograms.has(histogramName)) {
-        try {
-          Services.telemetry.registerAddonHistogram(metricAppName,
-            CUSTOM_HISTOGRAM_PREFIX + metricName,
-            Services.telemetry.HISTOGRAM_LINEAR, 1, 10000, 10);
-          developerHUD._customHistograms.add(histogramName);
-        } catch(err) {
-          console.error('Histogram error: ' + err);
-        }
+      // This is a call to add a value to an existing histogram.
+      if (typeof metric.value !== 'undefined') {
+        Services.telemetry.getAddonHistogram(metricAppName,
+          CUSTOM_HISTOGRAM_PREFIX + metricName).add(parseInt(metric.value, 10));
+        return;
+      }
+
+      // The histogram already exists and are not adding data to it.
+      if (developerHUD._customHistograms.has(histogramName)) {
+        return;
+      }
+
+      // This is a call to create a new histogram.
+      try {
+        let metricType = parseInt(metric.type, 10);
+        if (metricType === Services.telemetry.HISTOGRAM_COUNT) {
+          Services.telemetry.registerAddonHistogram(metricAppName,
+            CUSTOM_HISTOGRAM_PREFIX + metricName, metricType);
+        } else {
+          Services.telemetry.registerAddonHistogram(metricAppName,
+            CUSTOM_HISTOGRAM_PREFIX + metricName, metricType, metric.min,
+            metric.max, metric.buckets);
+        }
+        developerHUD._customHistograms.add(histogramName);
+      } catch (err) {
+        console.error('Histogram error: ' + err);
       }
-      Services.telemetry.getAddonHistogram(metricAppName,
-        CUSTOM_HISTOGRAM_PREFIX + metricName).add(parseInt(metric.value, 10));
     }
   }
 };
@@ -588,24 +603,40 @@ let consoleWatcher = {
     let TELEMETRY_IDENTIFIER_IDX = 0;
     let NAME_IDX = 1;
     let VALUE_IDX = 2;
+    let TYPE_IDX = 2;
+    let MIN_IDX = 3;
+    let MAX_IDX = 4;
+    let BUCKETS_IDX = 5;
+    let MAX_CUSTOM_ARGS = 6;
+    let MIN_CUSTOM_ARGS = 3;
 
     if (telemetryData[TELEMETRY_IDENTIFIER_IDX] != 'telemetry' ||
-        telemetryData.length < 3 || telemetryData.length > 4) {
+        telemetryData.length < MIN_CUSTOM_ARGS ||
+        telemetryData.length > MAX_CUSTOM_ARGS) {
       return;
     }
 
     let metric = {
-      name: telemetryData[NAME_IDX],
-      value: telemetryData[VALUE_IDX]
+      name: telemetryData[NAME_IDX]
     };
-    if (metric.name == 'MGMT') {
-      if (metric.value == 'TIMETOSHIP') {
+
+    if (metric.name === 'MGMT') {
+      metric.value = telemetryData[VALUE_IDX];
+      if (metric.value === 'TIMETOSHIP') {
         telemetryDebug('Received a Ship event');
         target._sendTelemetryData();
-      } else if (metric.value == 'CLEARMETRICS') {
+      } else if (metric.value === 'CLEARMETRICS') {
         target._clearTelemetryData();
       }
     } else {
+      if (telemetryData.length === MIN_CUSTOM_ARGS) {
+        metric.value = telemetryData[VALUE_IDX];
+      } else if (telemetryData.length === MAX_CUSTOM_ARGS) {
+        metric.type = telemetryData[TYPE_IDX];
+        metric.min = telemetryData[MIN_IDX];
+        metric.max = telemetryData[MAX_IDX];
+        metric.buckets = telemetryData[BUCKETS_IDX];
+      }
       metric.custom = true;
       target._logHistogram(metric);
     }