opencensus-zpages: Enforce strictNullChecks and noUnusedLocals (#432)

* opencensus-zpages: Enforce strictNullChecks and noUnusedLocals

* fix tests

Author: mayurkale22

packages/opencensus-exporter-zpages/src/zpages-frontend/latency-bucket-boundaries.ts

@@ -96,7 +96,7 @@ export class LatencyBucketBoundaries {
       case LatencyBucketBoundaries.SECONDx100_MAX:
         return '>100s';
       default:
-        return null;
+        throw new Error('unknown bucket boundary');
     }
   }
 
@@ -122,7 +122,7 @@ export class LatencyBucketBoundaries {
       case LatencyBucketBoundaries.SECONDx100_MAX:
         return 'SECONDx100_MAX';
       default:
-        return null;
+        throw new Error('unknown bucket boundary');
     }
   }
 
@@ -137,7 +137,7 @@ export class LatencyBucketBoundaries {
         return latency;
       }
     }
-    return null;
+    throw new Error('unknown bucket boundary');
   }
 
   /**

packages/opencensus-exporter-zpages/src/zpages-frontend/page-handlers/rpcz.page-handler.ts

@@ -48,22 +48,6 @@ export interface RpczData {
   measuresReceived: {[key: string]: ZMeasure};
 }
 
-enum DefaultMeasures {
-  CLIENT_SENT_MESSAGES_PER_RPC = 'grpc.io/client/sent_messages_per_rpc',
-  CLIENT_SENT_BYTES_PER_RPC = 'grpc.io/client/sent_bytes_per_rpc',
-  CLIENT_RECEIVED_MESSAGES_PER_RPC = 'grpc.io/client/received_messages_per_rpc',
-  CLIENT_RECEIVED_BYTES_PER_RPC = 'grpc.io/client/received_bytes_per_rpc',
-  CLIENT_ROUDTRIP_LATENCY = 'grpc.io/client/roundtrip_latency',
-  CLIENT_SERVER_LATENCY = 'grpc.io/client/server_latency',
-  CLIENT_STARTED_RPCS = 'grpc.io/client/started_rpcs',
-  SERVER_RECEIVED_MESSAGES_PER_RPC = 'grpc.io/server/received_messages_per_rpc',
-  SERVER_RECEIVED_BYTES_PER_RPC = 'grpc.io/server/received_bytes_per_rpc',
-  SERVER_SENT_MESSAGES_PER_RPC = 'grpc.io/server/sent_messages_per_rpc',
-  SERVER_SENT_BYTES_PER_RPC = 'grpc.io/server/sent_bytes_per_rpc',
-  SERVER_SERVER_LATENCY = 'grpc.io/server/server_latency',
-  SERVER_STARTED_RPCS = 'grpc.io/server/started_rpcs'
-}
-
 enum DefaultViews {
   CLIENT_SENT_BYTES_PER_RPC = 'grpc.io/client/sent_bytes_per_rpc',
   CLIENT_RECEIVED_BYTES_PER_RPC = 'grpc.io/client/received_bytes_per_rpc',
@@ -129,7 +113,7 @@ export class RpczPageHandler {
           method = snapshot.tagValues[serverMethodIndex].value;
           zMeasures = rpczData.measuresReceived;
         }
-        if (method) {
+        if (zMeasures && method) {
           if (!zMeasures[method]) {
             zMeasures[method] = this.newEmptyZMeasure();
           }

packages/opencensus-exporter-zpages/src/zpages-frontend/page-handlers/statsz.page-handler.ts

@@ -68,11 +68,11 @@ export class StatszPageHandler {
     /** keeps the folders that belong to the current folder  */
     const folders: FolderType = {};
     /** selected view to show */
-    let selectedView: View;
+    let selectedView: View|undefined;
     /** keeps HTML table content */
     let tableContent: string;
     /** keeps the stats and view data to load UI */
-    let statsViewData: StatsViewData;
+    let statsViewData: StatsViewData|undefined;
 
     // gets the path from user
     if (params.path) {
@@ -129,7 +129,7 @@ export class StatszPageHandler {
     if (selectedView) {
       const statsData = this.getStatsData(selectedView);
       const viewFile = this.loaderFile('statsz-view.ejs');
-      let viewContentFile: string;
+      let viewContentFile: string|undefined;
       let statsContent: string;
 
       switch (selectedView.aggregation) {

packages/opencensus-exporter-zpages/src/zpages-frontend/page-handlers/traceconfigz.page-handler.ts

@@ -19,8 +19,6 @@ import * as tracing from '@opencensus/nodejs';
 import * as ejs from 'ejs';
 import * as pkgDir from 'pkg-dir';
 
-import {ZpagesExporter} from '../../zpages';
-
 // The directory to search for templates.
 const templatesDir = `${pkgDir.sync(__dirname)}/templates`;
 
@@ -36,7 +34,7 @@ export interface TraceConfigzData {
 
 export class TraceConfigzPageHandler {
   /** Configuration defaults. Currently just the default sampling rate. */
-  private defaultConfig: {samplingRate: number;};
+  private defaultConfig?: {samplingRate: number;};
 
   /**
    * Generate Zpages Trace Config HTML Page
@@ -83,7 +81,6 @@ export class TraceConfigzPageHandler {
   private saveChanges(query: Partial<TraceConfigzParams>): void {
     /** restore the config to default */
     if (query.change === 'restore_default') {
-      const exporter = tracing.exporter as ZpagesExporter;
       tracing.tracer.sampler =
           SamplerBuilder.getSampler(this.defaultConfig!.samplingRate);
       return;
@@ -107,6 +104,7 @@ export class TraceConfigzPageHandler {
     } else if (samplingProbability === 'never') {
       return 0;
     }
-    return Number(samplingProbability.match(/\((.*)\)/)[1]);
+    const probability = samplingProbability.match(/\((.*)\)/);
+    return probability ? Number(probability[1]) : 1 / 10000;
   }
 }

packages/opencensus-exporter-zpages/src/zpages-frontend/page-handlers/tracez.page-handler.ts

@@ -84,7 +84,7 @@ const getCanonicalCode = (status: number) => {
     case 16:
       return 'UNAUTHENTICATED';
     default:
-      return null;
+      return 'UNKNOWN';
   }
 };
 

packages/opencensus-exporter-zpages/src/zpages.ts

@@ -42,7 +42,7 @@ export class ZpagesExporter implements Exporter, StatsEventListener {
   static readonly defaultOptions = {port: 8080, startServer: true};
 
   private app: express.Application;
-  private server: http.Server;
+  private server?: http.Server;
   private port: number;
   private traces: Map<string, Span[]> = new Map();
   private logger: Logger;
@@ -208,6 +208,8 @@ export class ZpagesExporter implements Exporter, StatsEventListener {
    * @param callback A function that will be called when the server is stopped.
    */
   stopServer(callback?: () => void) {
-    this.server.close(callback);
+    if (this.server) {
+      this.server.close(callback);
+    }
   }
 }

packages/opencensus-exporter-zpages/test/test-zpages.ts

@@ -19,7 +19,6 @@ import * as assert from 'assert';
 import axios from 'axios';
 import * as http from 'http';
 import * as qs from 'querystring';
-
 import {ZpagesExporter, ZpagesExporterOptions} from '../src/zpages';
 import {RpczData} from '../src/zpages-frontend/page-handlers/rpcz.page-handler';
 import {StatsViewData, StatszParams} from '../src/zpages-frontend/page-handlers/statsz.page-handler';
@@ -268,7 +267,7 @@ describe('Zpages Exporter', () => {
       it('should get view information', async () => {
         const view = globalStats.createView(
             'test/CountView', measure, AggregationType.COUNT, tagKeys,
-            'A count test', null);
+            'A count test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -283,7 +282,7 @@ describe('Zpages Exporter', () => {
       it('should get stats for view', async () => {
         const view = globalStats.createView(
             'test/CountView', measure, AggregationType.COUNT, tagKeys,
-            'A count test', null);
+            'A count test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -301,8 +300,8 @@ describe('Zpages Exporter', () => {
       it('should get view information', async () => {
         globalStats.registerExporter(zpages);
         const view = globalStats.createView(
-            'test/SumView', measure, AggregationType.SUM, tagKeys, 'A sum test',
-            null);
+            'test/SumView', measure, AggregationType.SUM, tagKeys,
+            'A sum test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -317,8 +316,8 @@ describe('Zpages Exporter', () => {
       it('should get stats for view', async () => {
         globalStats.registerExporter(zpages);
         const view = globalStats.createView(
-            'test/SumView', measure, AggregationType.SUM, tagKeys, 'A sum test',
-            null);
+            'test/SumView', measure, AggregationType.SUM, tagKeys,
+            'A sum test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -337,7 +336,7 @@ describe('Zpages Exporter', () => {
         globalStats.registerExporter(zpages);
         const view = globalStats.createView(
             'test/LastValueView', measure, AggregationType.LAST_VALUE, tagKeys,
-            'A last value test', null);
+            'A last value test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -353,7 +352,7 @@ describe('Zpages Exporter', () => {
         globalStats.registerExporter(zpages);
         const view = globalStats.createView(
             'test/LastValueView', measure, AggregationType.LAST_VALUE, tagKeys,
-            'A last value test', null);
+            'A last value test');
         globalStats.registerView(view);
         globalStats.record([measurement, measurement2], tagMap);
 
@@ -474,13 +473,13 @@ describe('Zpages Exporter', () => {
       const view4 = globalStats.createView(
           'grpc.io/client/completed_rpcs', measure3, AggregationType.COUNT,
           [GRPC_CLIENT_METHOD, GRPC_CLIENT_STATUS],
-          'Number of completed client RPCs', null);
+          'Number of completed client RPCs');
       globalStats.registerView(view4);
 
       const view5 = globalStats.createView(
           'grpc.io/client/started_rpcs', measure4, AggregationType.COUNT,
           [GRPC_CLIENT_METHOD, GRPC_CLIENT_STATUS],
-          'Number of started client RPCs', null);
+          'Number of started client RPCs');
       globalStats.registerView(view5);
 
       const measurement = {measure, value: 22000};
@@ -552,13 +551,13 @@ describe('Zpages Exporter', () => {
       const view4 = globalStats.createView(
           'grpc.io/server/completed_rpcs', measure7, AggregationType.COUNT,
           [GRPC_SERVER_METHOD, GRPC_SERVER_STATUS],
-          'Number of completed client RPCs', null);
+          'Number of completed client RPCs');
       globalStats.registerView(view4);
 
       const view5 = globalStats.createView(
           'grpc.io/server/started_rpcs', measure8, AggregationType.COUNT,
           [GRPC_SERVER_METHOD, GRPC_SERVER_STATUS],
-          'Number of started client RPCs', null);
+          'Number of started client RPCs');
       globalStats.registerView(view5);
 
       const measurement6 = {measure: measure5, value: 2200};

packages/opencensus-exporter-zpages/tsconfig.json

@@ -6,7 +6,8 @@
     "pretty": true,
     "module": "commonjs",
     "target": "es6",
-    "strictNullChecks": false
+    "strictNullChecks": true,
+    "noUnusedLocals": true
   },
   "include": [
     "src/**/*.ts",