Consolidating Span and RootSpan to allow Spans to recursively have children. (#78)

Author: crdgonzalezca

packages/opencensus-web-core/src/exporters/noop_exporter.ts

@@ -17,11 +17,11 @@
 import * as webTypes from '@opencensus/web-types';
 
 export class NoopExporter implements webTypes.Exporter {
-  publish(roots: webTypes.RootSpan[]): Promise<number | string | void> {
+  publish(roots: webTypes.Span[]): Promise<number | string | void> {
     return Promise.resolve();
   }
 
-  onStartSpan(root: webTypes.RootSpan) {}
+  onStartSpan(root: webTypes.Span) {}
 
-  onEndSpan(root: webTypes.RootSpan) {}
+  onEndSpan(root: webTypes.Span) {}
 }

packages/opencensus-web-core/src/trace/model/root-span.ts

@@ -19,13 +19,7 @@ import { randomTraceId } from '../../common/id-util';
 import { Span } from './span';
 
 /** Simple mock root span for use in use tests. */
-export class RootSpan extends Span implements webTypes.RootSpan {
-  /** A list of child spans. */
-  spans: Span[] = [];
-
-  /** A number of children. */
-  private numberOfChildrenLocal: number;
-
+export class RootSpan extends Span {
   constructor(
     /** Trace associated with this root span. */
     private readonly tracer: webTypes.Tracer,
@@ -47,41 +41,6 @@ export class RootSpan extends Span implements webTypes.RootSpan {
     } else {
       this.traceId = randomTraceId();
     }
-
-    this.numberOfChildrenLocal = 0;
-  }
-
-  /** Gets the number of child span created for this span. */
-  get numberOfChildren(): number {
-    return this.numberOfChildrenLocal;
-  }
-
-  /**
-   * Starts a new child span in the root span.
-   * @param nameOrOptions Span name string or SpanOptions object.
-   * @param kind Span kind if not using options object.
-   * @param parentSpanId Span parent ID.
-   */
-  startChildSpan(
-    nameOrOptions?: string | webTypes.SpanOptions,
-    kind?: webTypes.SpanKind
-  ): Span {
-    this.numberOfChildrenLocal++;
-    const child = new Span();
-    child.traceId = this.traceId;
-    child.traceState = this.traceState;
-
-    const spanName =
-      typeof nameOrOptions === 'object' ? nameOrOptions.name : nameOrOptions;
-    const spanKind =
-      typeof nameOrOptions === 'object' ? nameOrOptions.kind : kind;
-    if (spanName) child.name = spanName;
-    if (spanKind) child.kind = spanKind;
-
-    child.start();
-    child.parentSpanId = this.id;
-    this.spans.push(child);
-    return child;
   }
 
   start() {

packages/opencensus-web-core/src/trace/model/span.ts

@@ -27,7 +27,9 @@ export class Span implements webTypes.Span {
   constructor(
     /** The ID of this span. Defaults to a random span ID. */
     public id = randomSpanId()
-  ) {}
+  ) {
+    this.numberOfChildrenLocal = 0;
+  }
 
   /** If the parent span is in another process. */
   remoteParent = false;
@@ -77,6 +79,12 @@ export class Span implements webTypes.Span {
   /** Start time of the span as measured by the browser performance clock. */
   startPerfTime = 0;
 
+  /** A list of child spans. */
+  spans: Span[] = [];
+
+  /** A number of children. */
+  private numberOfChildrenLocal: number;
+
   /**
    * Number of dropped attributes. This is always zero because OpenCensus web
    * does not implement attribute dropping (but may be done by agent on export).
@@ -113,6 +121,11 @@ export class Span implements webTypes.Span {
   /** End time of the span as measured by the browser performance clock. */
   endPerfTime = 0;
 
+  /** Gets the number of child span created for this span. */
+  get numberOfChildren(): number {
+    return this.numberOfChildrenLocal;
+  }
+
   /** End time of the span as a Date. */
   get endTime(): Date {
     return getDateForPerfTime(this.endPerfTime);
@@ -138,6 +151,44 @@ export class Span implements webTypes.Span {
     };
   }
 
+  /** Recursively gets the descendant spans. */
+  allDescendants(): webTypes.Span[] {
+    return this.spans.reduce((acc: webTypes.Span[], cur) => {
+      acc.push(cur);
+      const desc = cur.allDescendants();
+      acc = acc.concat(desc);
+      return acc;
+    }, []);
+  }
+
+  /**
+   * Starts a new child span.
+   * @param nameOrOptions Span name string or SpanOptions object.
+   * @param kind Span kind if not using options object.
+   * @param parentSpanId Span parent ID.
+   */
+  startChildSpan(
+    nameOrOptions?: string | webTypes.SpanOptions,
+    kind?: webTypes.SpanKind
+  ): Span {
+    this.numberOfChildrenLocal++;
+    const child = new Span();
+    child.traceId = this.traceId;
+    child.traceState = this.traceState;
+
+    const spanName =
+      typeof nameOrOptions === 'object' ? nameOrOptions.name : nameOrOptions;
+    const spanKind =
+      typeof nameOrOptions === 'object' ? nameOrOptions.kind : kind;
+    if (spanName) child.name = spanName;
+    if (spanKind) child.kind = spanKind;
+
+    child.start();
+    child.parentSpanId = this.id;
+    this.spans.push(child);
+    return child;
+  }
+
   /**
    * Adds an attribute to the span.
    * @param key Describes the value added.

packages/opencensus-web-core/src/trace/model/tracer.ts

@@ -25,7 +25,7 @@ const NO_HEADERS_PROPAGATION = new NoHeadersPropagation();
 /** Tracer manages the current root span and trace header propagation. */
 export class Tracer implements webTypes.Tracer {
   /** Get and set the currentRootSpan of the tracer. */
-  currentRootSpan: RootSpan = new RootSpan(this);
+  currentRootSpan: Span = new RootSpan(this);
 
   /**
    * A sampler used to make trace sample decisions. In the case of
@@ -80,24 +80,21 @@ export class Tracer implements webTypes.Tracer {
    * @param fn Callback function
    * @returns The callback return
    */
-  startRootSpan<T>(
-    options: webTypes.TraceOptions,
-    fn: (root: RootSpan) => T
-  ): T {
+  startRootSpan<T>(options: webTypes.TraceOptions, fn: (root: Span) => T): T {
     this.currentRootSpan = new RootSpan(this, options);
     this.currentRootSpan.start();
     return fn(this.currentRootSpan);
   }
 
   /** Notifies listeners of the span start. */
-  onStartSpan(root: webTypes.RootSpan) {
+  onStartSpan(root: webTypes.Span) {
     for (const listener of this.eventListeners) {
       listener.onStartSpan(root);
     }
   }
 
   /** Notifies listeners of the span end. */
-  onEndSpan(root: webTypes.RootSpan) {
+  onEndSpan(root: webTypes.Span) {
     for (const listener of this.eventListeners) {
       listener.onEndSpan(root);
     }

packages/opencensus-web-core/test/test-root-span.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import { SpanKind, SpanOptions } from '@opencensus/web-types';
+import { SpanKind } from '@opencensus/web-types';
 import { RootSpan } from '../src/trace/model/root-span';
 import { Tracer } from '../src/trace/model/tracer';
 
@@ -51,40 +51,6 @@ describe('RootSpan', () => {
     });
   });
 
-  describe('startChildSpan', () => {
-    it('appends to spans list based on root id and state', () => {
-      root.traceId = '00000000000000000000000000000001';
-      root.traceState = 'a=b';
-
-      const childSpan = root.startChildSpan('child1', SpanKind.CLIENT);
-
-      expect(childSpan.traceId).toBe('00000000000000000000000000000001');
-      expect(childSpan.traceState).toBe('a=b');
-      expect(childSpan.name).toBe('child1');
-      expect(childSpan.kind).toBe(SpanKind.CLIENT);
-      expect(childSpan.parentSpanId).toBe(root.id);
-      expect(root.spans).toEqual([childSpan]);
-    });
-
-    it('allows specifying SpanOptions object with name and kind', () => {
-      root.traceId = '00000000000000000000000000000001';
-      root.traceState = 'a=b';
-
-      const spanOptions: SpanOptions = {
-        name: 'child1',
-        kind: SpanKind.CLIENT,
-      };
-      const childSpan = root.startChildSpan(spanOptions);
-
-      expect(childSpan.traceId).toBe('00000000000000000000000000000001');
-      expect(childSpan.traceState).toBe('a=b');
-      expect(childSpan.name).toBe('child1');
-      expect(childSpan.kind).toBe(SpanKind.CLIENT);
-      expect(childSpan.parentSpanId).toBe(root.id);
-      expect(root.spans).toEqual([childSpan]);
-    });
-  });
-
   describe('start', () => {
     it('sets start time and calls onStartSpan for tracer', () => {
       spyOn(tracer, 'onStartSpan');
@@ -121,18 +87,36 @@ describe('RootSpan', () => {
     });
   });
 
-  describe('get numberOfChildren()', () => {
-    it('should get numberOfChildren from rootspan instance', () => {
-      root = new RootSpan(tracer);
+  describe('nested spans', () => {
+    it('should get nested spans from rootspan instance', () => {
       root.start();
       expect(root.numberOfChildren).toBe(0);
-      root.startChildSpan('spanName', SpanKind.UNSPECIFIED);
+      const child1 = root.startChildSpan('child1', SpanKind.UNSPECIFIED);
       expect(root.numberOfChildren).toBe(1);
+      expect(child1.numberOfChildren).toBe(0);
+      const child2 = root.startChildSpan('child2', SpanKind.UNSPECIFIED);
+      expect(root.numberOfChildren).toBe(2);
+      const grandchild1 = child1.startChildSpan({
+        name: 'grandchild1',
+        kind: SpanKind.UNSPECIFIED,
+      });
+      expect(root.numberOfChildren).toBe(2);
+      expect(child1.numberOfChildren).toBe(1);
+      expect(child2.numberOfChildren).toBe(0);
+      expect(grandchild1.numberOfChildren).toBe(0);
+
+      expect(child1).toBe(root.spans[0]);
+      expect(child2).toBe(root.spans[1]);
+      expect(grandchild1.parentSpanId).toBe(child1.id);
+
+      expect(child1.spans.length).toBe(1);
+      expect(grandchild1).toBe(child1.spans[0]);
+
+      expect(child2.spans.length).toBe(0);
+      expect(child2.spans.length).toBe(0);
+      expect(grandchild1.spans.length).toBe(0);
 
-      for (let i = 0; i < 10; i++) {
-        root.startChildSpan('spanName' + i, SpanKind.UNSPECIFIED);
-      }
-      expect(root.numberOfChildren).toBe(11);
+      expect(root.allDescendants().length).toBe(3);
     });
   });
 });

packages/opencensus-web-core/test/test-span.ts

@@ -14,7 +14,12 @@
  * limitations under the License.
  */
 
-import { LinkType, MessageEventType } from '@opencensus/web-types';
+import {
+  LinkType,
+  MessageEventType,
+  SpanKind,
+  SpanOptions,
+} from '@opencensus/web-types';
 import { Span } from '../src/trace/model/span';
 import { mockGetterOrValue, restoreGetterOrValue } from './util';
 
@@ -181,4 +186,52 @@ describe('Span', () => {
       ]);
     });
   });
+
+  describe('get numberOfChildren()', () => {
+    it('should get numberOfChildren from span instance', () => {
+      span.start();
+      expect(span.numberOfChildren).toBe(0);
+      span.startChildSpan('spanName', SpanKind.UNSPECIFIED);
+      expect(span.numberOfChildren).toBe(1);
+
+      for (let i = 0; i < 10; i++) {
+        span.startChildSpan('spanName' + i, SpanKind.UNSPECIFIED);
+      }
+      expect(span.numberOfChildren).toBe(11);
+    });
+  });
+
+  describe('startChildSpan', () => {
+    it('appends to spans list based on root id and state', () => {
+      span.traceId = '00000000000000000000000000000001';
+      span.traceState = 'a=b';
+
+      const childSpan = span.startChildSpan('child1', SpanKind.CLIENT);
+
+      expect(childSpan.traceId).toBe('00000000000000000000000000000001');
+      expect(childSpan.traceState).toBe('a=b');
+      expect(childSpan.name).toBe('child1');
+      expect(childSpan.kind).toBe(SpanKind.CLIENT);
+      expect(childSpan.parentSpanId).toBe(span.id);
+      expect(span.spans).toEqual([childSpan]);
+    });
+
+    it('allows specifying SpanOptions object with name and kind', () => {
+      span.traceId = '00000000000000000000000000000001';
+      span.traceState = 'a=b';
+
+      const spanOptions: SpanOptions = {
+        name: 'child1',
+        kind: SpanKind.CLIENT,
+      };
+      const childSpan = span.startChildSpan(spanOptions);
+
+      expect(childSpan.traceId).toBe('00000000000000000000000000000001');
+      expect(childSpan.traceState).toBe('a=b');
+      expect(childSpan.name).toBe('child1');
+      expect(childSpan.kind).toBe(SpanKind.CLIENT);
+      expect(childSpan.parentSpanId).toBe(span.id);
+      expect(span.spans).toEqual([childSpan]);
+    });
+  });
 });

packages/opencensus-web-types/package.json

@@ -7,7 +7,7 @@
   "scripts": {
     "build": "npm run compile",
     "clean": "rimraf build/*",
-    "copytypes": "node scripts/copy-types.js 'v0.0.11' && npm run fix",
+    "copytypes": "node scripts/copy-types.js 'abd41dbc0f2f5836980ae9d79048a81d58a9956f' && npm run fix",
     "check": "gts check",
     "compile": "tsc -p .",
     "fix": "gts fix",

packages/opencensus-web-types/src/exporters/types.ts

@@ -25,7 +25,7 @@ export interface Exporter extends modelTypes.SpanEventListener {
    * Sends a list of root spans to the service.
    * @param rootSpans A list of root spans to publish.
    */
-  publish(rootSpans: modelTypes.RootSpan[]): Promise<number | string | void>;
+  publish(rootSpans: modelTypes.Span[]): Promise<number | string | void>;
 }
 
 /**