feat(cloudwatch): legend positions in GraphWidgets

packages/@aws-cdk/aws-cloudwatch/README.md

@@ -241,6 +241,17 @@ dashboard.addWidgets(new GraphWidget({
 }));
 ```
 
+The graph legend can be adjusted from the default position at bottom of the widget.
+
+```ts
+dashboard.addWidgets(new GraphWidget({
+  // ...
+  // ...
+
+  legendPosition: LegendPosition.RIGHT,
+}));
+```
+
 ### Alarm widget
 
 An alarm widget shows the graph and the alarm line of a single alarm:

packages/@aws-cdk/aws-cloudwatch/lib/graph.ts

@@ -173,6 +173,13 @@ export interface GraphWidgetProps extends MetricWidgetProps {
    * @default - None
    */
   readonly rightYAxis?: YAxisProps;
+
+  /**
+   * Position of the legend
+   *
+   * @default - bottom
+   */
+  readonly legendPosition?: LegendPosition;
 }
 
 /**
@@ -210,6 +217,7 @@ export class GraphWidget extends ConcreteWidget {
           left: this.props.leftYAxis !== undefined ? this.props.leftYAxis : undefined,
           right: this.props.rightYAxis !== undefined ? this.props.rightYAxis : undefined,
         },
+        legend: this.props.legendPosition !== undefined ? { position: this.props.legendPosition } : undefined,
       },
     }];
   }
@@ -349,6 +357,26 @@ export class Color {
   public static readonly RED = '#d62728';
 }
 
+/**
+ * The position of the legend on a GraphWidget.
+ */
+export enum LegendPosition {
+  /**
+   * Legend appears below the graph (default).
+   */
+  BOTTOM = 'bottom',
+
+  /**
+   * Add shading above the annotation
+   */
+  RIGHT = 'right',
+
+  /**
+   * Add shading below the annotation
+   */
+  HIDDEN = 'hidden'
+}
+
 function mapAnnotation(yAxis: string): ((x: HorizontalAnnotation) => any) {
   return (a: HorizontalAnnotation) => {
     return { ...a, yAxis };

packages/@aws-cdk/aws-cloudwatch/test/test.graphs.ts

@@ -1,6 +1,6 @@
 import { Stack } from '@aws-cdk/core';
 import { Test } from 'nodeunit';
-import { Alarm, AlarmWidget, Color, GraphWidget, LogQueryWidget, Metric, Shading, SingleValueWidget } from '../lib';
+import { Alarm, AlarmWidget, Color, GraphWidget, LegendPosition, LogQueryWidget, Metric, Shading, SingleValueWidget } from '../lib';
 
 export = {
   'add stacked property to graphs'(test: Test) {
@@ -393,4 +393,33 @@ export = {
     test.deepEqual(stack.resolve(widget.toJson())[0].properties.annotations.horizontal[0], { yAxis: 'left', value: 100, color: '#d62728' });
     test.done();
   },
+
+  'legend position is respected in constructor'(test: Test) {
+    // WHEN
+    const stack = new Stack();
+    const widget = new GraphWidget({
+      left: [new Metric({ namespace: 'CDK', metricName: 'Test' }) ],
+      legendPosition: LegendPosition.RIGHT,
+    });
+
+    // THEN
+    test.deepEqual(stack.resolve(widget.toJson()), [{
+      type: 'metric',
+      width: 6,
+      height: 6,
+      properties: {
+        view: 'timeSeries',
+        region: { Ref: 'AWS::Region' },
+        metrics: [
+          ['CDK', 'Test'],
+        ],
+        yAxis: {},
+        legend: {
+          position: 'right',
+        },
+      },
+    }]);
+
+    test.done();
+  },
 };