First pass of changes

Author: tmitchel2

flow/aws-sdk-promise.js

@@ -334,8 +334,8 @@ declare module 'aws-sdk-promise' {
   };
 
   declare type ProvisionedThroughput = {
-     LastDecreaseDateTime: number,
-     LastIncreaseDateTime: number,
+     LastDecreaseDateTime: string,
+     LastIncreaseDateTime: string,
      NumberOfDecreasesToday: number,
      ReadCapacityUnits: number,
      WriteCapacityUnits: number,

scripts/localtest.js

@@ -1,125 +1,28 @@
 /* @flow */
-import { json, stats, warning, invariant } from './Global';
-import CloudWatch from './CloudWatch';
-import type { TableConsumedCapacityDescription } from './FlowTypes';
-import type {
-  TableDescription,
-  GetMetricStatisticsResponse,
-  Dimension,
-} from 'aws-sdk-promise';
+import { invariant } from './Global';
+import CapacityCalculatorBase from './capacity/CapacityCalculatorBase';
+import type { GetMetricStatisticsResponse } from 'aws-sdk-promise';
+import type { StatisticSettings } from './flow/FlowTypes';
 
-export default class CapacityCalculator {
-  _cw: CloudWatch;
+export default class CapacityCalculator extends CapacityCalculatorBase {
 
-  constructor(cloudWatch: CloudWatch) {
-    invariant(typeof cloudWatch !== 'undefined', 'Parameter \'cloudWatch\' is not set');
-    this._cw = cloudWatch;
+  // Get the region
+  getCloudWatchRegion() {
+    return 'us-east-1';
   }
 
-  async describeTableConsumedCapacityAsync(params: TableDescription)
-    : Promise<TableConsumedCapacityDescription> {
-    let sw = stats
-      .timer('DynamoDB.describeTableConsumedCapacityAsync')
-      .start();
-
-    try {
-      invariant(typeof params !== 'undefined', 'Parameter \'params\' is not set');
-
-      // Make all the requests concurrently
-      let tableRead = this.getConsumedCapacityAsync(true, params.TableName, null);
-      let tableWrite = this.getConsumedCapacityAsync(false, params.TableName, null);
-
-      let gsiReads = (params.GlobalSecondaryIndexes || [])
-        .map(gsi => this.getConsumedCapacityAsync(true, params.TableName, gsi.IndexName));
-
-      let gsiWrites = (params.GlobalSecondaryIndexes || [])
-        .map(gsi => this.getConsumedCapacityAsync(false, params.TableName, gsi.IndexName));
-
-      // Await on the results
-      let tableConsumedRead = await tableRead;
-      let tableConsumedWrite = await tableWrite;
-      let gsiConsumedReads = await Promise.all(gsiReads);
-      let gsiConsumedWrites = await Promise.all(gsiWrites);
-
-      // Format results
-      let gsis = gsiConsumedReads.map((read, i) => {
-        let write = gsiConsumedWrites[i];
-        return {
-          // $FlowIgnore: The indexName is not null in this case
-          IndexName: read.globalSecondaryIndexName,
-          ConsumedThroughput: {
-            ReadCapacityUnits: read.value,
-            WriteCapacityUnits: write.value
-          }
-        };
-      });
-
-      return {
-        TableName: params.TableName,
-        ConsumedThroughput: {
-          ReadCapacityUnits: tableConsumedRead.value,
-          WriteCapacityUnits: tableConsumedWrite.value
-        },
-        GlobalSecondaryIndexes: gsis
-      };
-    } catch (ex) {
-      warning(JSON.stringify({
-        class: 'CapacityCalculator',
-        function: 'describeTableConsumedCapacityAsync',
-        params,
-      }, null, json.padding));
-      throw ex;
-    } finally {
-      sw.end();
-    }
-  }
-
-  async getConsumedCapacityAsync(
-    isRead: boolean, tableName: string, globalSecondaryIndexName: ?string) {
-    try {
-      invariant(typeof isRead !== 'undefined', 'Parameter \'isRead\' is not set');
-      invariant(typeof tableName !== 'undefined', 'Parameter \'tableName\' is not set');
-      invariant(typeof globalSecondaryIndexName !== 'undefined',
-        'Parameter \'globalSecondaryIndexName\' is not set');
-
-      // These values determine how many minutes worth of metrics
-      let durationMinutes = 5;
-      let periodMinutes = 1;
-
-      let EndTime = new Date();
-      let StartTime = new Date();
-      StartTime.setTime(EndTime - (60000 * durationMinutes));
-      let MetricName = isRead ? 'ConsumedReadCapacityUnits' : 'ConsumedWriteCapacityUnits';
-      let Dimensions = this.getDimensions(tableName, globalSecondaryIndexName);
-      let params = {
-        Namespace: 'AWS/DynamoDB',
-        MetricName,
-        Dimensions,
-        StartTime,
-        EndTime,
-        Period: (periodMinutes * 60),
-        Statistics: [ 'Average' ],
-        Unit: 'Count'
-      };
-
-      let statistics = await this._cw.getMetricStatisticsAsync(params);
-      let value = this.getProjectedValue(statistics);
-      return {
-        tableName,
-        globalSecondaryIndexName,
-        value
-      };
-    } catch (ex) {
-      warning(JSON.stringify({
-        class: 'CapacityCalculator',
-        function: 'getConsumedCapacityAsync',
-        isRead, tableName, globalSecondaryIndexName,
-      }, null, json.padding));
-      throw ex;
-    }
+  getStatisticSettings(): StatisticSettings {
+    return {
+      count: 5,
+      spanMinutes: 1,
+      type: 'Average',
+    };
   }
 
+  // Gets the projected capacity value based on the cloudwatch datapoints
   getProjectedValue(data: GetMetricStatisticsResponse) {
+    invariant(data != null, 'Parameter \'data\' is not set');
+
     if (data.Datapoints.length === 0) {
       return 0;
     }
@@ -128,18 +31,6 @@ export default class CapacityCalculator {
     // 1. Query 5 average readings each spanning a minute
     // 2. Select the Max value from those 5 readings
     let averages = data.Datapoints.map(dp => dp.Average);
-    let value = Math.max(...averages);
-    return value;
-  }
-
-  getDimensions(tableName: string, globalSecondaryIndexName: ?string): Dimension[] {
-    if (globalSecondaryIndexName) {
-      return [
-        { Name: 'TableName', Value: tableName},
-        { Name: 'GlobalSecondaryIndex', Value: globalSecondaryIndexName}
-      ];
-    }
-
-    return [ { Name: 'TableName', Value: tableName} ];
+    return Math.max(...averages);
   }
 }