Enable DynamoDB stream on repo activity table

src/cdk/stacks/StorageStack.ts

@@ -1,10 +1,15 @@
 import { Aws, Duration, RemovalPolicy, Stack } from 'aws-cdk-lib'
 import { Construct } from 'constructs'
-import { AttributeType, TableV2 } from 'aws-cdk-lib/aws-dynamodb'
+import { AttributeType, StreamViewType, TableV2 } from 'aws-cdk-lib/aws-dynamodb'
 import { saveInSSMViaCloudFormation } from '../support/ssm'
 import { AllStacksProps } from '../config/allStacksProps'
 import { BlockPublicAccess, Bucket, IBucket, ObjectOwnership } from 'aws-cdk-lib/aws-s3'
-import { SSM_PARAM_NAMES, SsmParamName, ssmTableNamePath } from '../../multipleContexts/ssmParams'
+import {
+  SSM_PARAM_NAMES,
+  SsmParamName,
+  ssmTableNamePath,
+  ssmTableStreamPath
+} from '../../multipleContexts/ssmParams'
 import { CICADA_TABLE_IDS, CicadaTableId, tableConfigurations } from '../../multipleContexts/dynamoDBTables'
 import { CfnDatabase } from 'aws-cdk-lib/aws-glue'
 import { CfnWorkGroup } from 'aws-cdk-lib/aws-athena'
@@ -48,6 +53,11 @@ function defineTable(scope: Construct, props: AllStacksProps, tableId: CicadaTab
       name: 'PK',
       type: AttributeType.STRING
     },
+    ...(config.stream
+      ? {
+          dynamoStream: StreamViewType.NEW_IMAGE
+        }
+      : {}),
     ...(config.hasSortKey
       ? {
           sortKey: {
@@ -76,6 +86,13 @@ function defineTable(scope: Construct, props: AllStacksProps, tableId: CicadaTab
   })
 
   saveInSSMViaCloudFormation(scope, props, ssmTableNamePath(tableId), table.tableName)
+
+  if (config.stream) {
+    if (tableId !== 'github-repo-activity')
+      throw new Error(`Streaming config not currently setup for table ${tableId}`)
+    if (!table.tableStreamArn) throw new Error(`Stream has not been configured for table ${tableId}`)
+    saveInSSMViaCloudFormation(scope, props, ssmTableStreamPath(tableId), table.tableStreamArn)
+  }
 }
 
 function defineBucket(

src/multipleContexts/dynamoDBTables.ts

@@ -2,6 +2,7 @@
 // Used by CDK for deployment and application code for configuration
 
 // If adding here, also add to SsmTableNameParamName type
+
 export const CICADA_TABLE_IDS = [
   'github-installations',
   'github-users',
@@ -15,40 +16,47 @@ export const CICADA_TABLE_IDS = [
 export type CicadaTableId = (typeof CICADA_TABLE_IDS)[number]
 
 interface CicadaTableConfig {
-  hasSortKey: boolean
-  hasGSI1: boolean
+  readonly hasSortKey: boolean
+  readonly hasGSI1: boolean
+  readonly stream: boolean
+}
+
+const allFalseConfig: CicadaTableConfig = {
+  hasGSI1: false,
+  hasSortKey: false,
+  stream: false
 }
 
 export const tableConfigurations: Record<CicadaTableId, CicadaTableConfig> = {
-  'github-installations': {
-    hasSortKey: false,
-    hasGSI1: false
-  },
-  'github-users': {
-    hasSortKey: false,
-    hasGSI1: false
-  },
+  'github-installations': allFalseConfig,
+  'github-users': allFalseConfig,
   'github-account-memberships': {
+    ...allFalseConfig,
     hasSortKey: true,
     hasGSI1: true
   },
   'github-repositories': {
+    ...allFalseConfig,
     hasSortKey: true,
     hasGSI1: false
   },
   'github-repo-activity': {
     hasSortKey: true,
-    hasGSI1: true
+    hasGSI1: true,
+    stream: true
   },
   'github-latest-workflow-runs': {
+    ...allFalseConfig,
     hasSortKey: true,
     hasGSI1: true
   },
   'github-latest-pushes-per-ref': {
+    ...allFalseConfig,
     hasSortKey: true,
     hasGSI1: true
   },
   'web-push-subscriptions': {
+    ...allFalseConfig,
     hasSortKey: true,
     hasGSI1: false
   }

src/multipleContexts/ssmParams.ts

@@ -50,6 +50,11 @@ export function ssmTableNamePath(id: CicadaTableId): SsmParamName {
   return `resources/table/${id}`
 }
 
+// For now, only table with a stream
+export function ssmTableStreamPath(id: 'github-repo-activity'): SsmParamName {
+  return `resources/tableStreamArn/${id}`
+}
+
 export function createFullParameterName({ appName }: { appName: string }, key: string) {
   return `/${appName}/${key}`
 }