Lambda Function Cache-Aside with DSQL

* Added new project
* Implemented with CDK / TypeScript
* Lambda Function build with Rust
* Created README

.gitignore

@@ -10,3 +10,6 @@ target
 
 # These are backup files generated by rustfmt
 **/*.rs.bk
+*.DS_STORE*
+*node_modules*
+*cdk.out*

example/aws/cache-aside-dsql-lambda/README.md

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+<img src="https://docs.momentohq.com/img/momento-logo-forest.svg" alt="logo" width="400"/>
+
+[![project status](https://momentohq.github.io/standards-and-practices/badges/project-status-official.svg)](https://github.com/momentohq/standards-and-practices/blob/main/docs/momento-on-github.md)
+[![project stability](https://momentohq.github.io/standards-and-practices/badges/project-stability-beta.svg)](https://github.com/momentohq/standards-and-practices/blob/main/docs/momento-on-github.md)
+
+
+# Momento Rust SDK - AWS Lambda CDK Example
+
+This directory contains an example project defining a Rust-based AWS Lambda function that implements a cache-aside strategy when working with AWS DSQL and uses the Momento Rust SDK to interact with the Cache.
+
+The Lambda function is deployed using the AWS Cloud Development Kit (CDK).
+
+## Example Requirements
+
+- Follow the [installation guide](https://doc.rust-lang.org/cargo/getting-started/installation.html) to install Rust and Cargo.
+- You will also need the [cargo-lambda cargo extension](https://www.cargo-lambda.info/)
+- The CDK code in this repo is written in TypeScript, so you will need `Node.js` version 16 or later, and a compatible
+  version of `npm` installed. If you don't have these, we recommend [nodenv](https://github.com/nodenv/nodenv).
+- To get started with Momento you will need a Momento API key. You can get one from the [Momento Console](https://console.gomomento.com).
+
+## Building and Deploying the Lambda Function
+
+This solution uses SQLx which requires connecting to the Database to build the `.sqlx` prepared query directory.  As of this writing, working with it and DSQL is a challenge so the easiest way to get this up and running is to create a local Postgres instance in Docker, build the table there, point the DATABASE_URL at that local container, and then run the DDL queries against DSQL when done.
+
+To build and deploy the Lambda function, first make sure that your AWS credentials are set up properly (via env vars or ~/.aws/credentials file). Then all you need to do is run the following commands:
+
+```bash
+cd infra
+export DATABASE_URL=<Local Postgre Connection String> 
+export CLUSTER_ENDPOINT=<DSQL Cluster Endpoint>
+export MOMENTO_API_KEY=<Momento API Key>
+cdk deploy
+```
+
+After the lambda is deployed, you can use the defined FunctionURL on the Lambda Function and supply and `?id=` to the URL for the Item in your database.  Make sure to build a table in DSQL that matches the Rust `CacheableItem` struct definition.
+
+## Interesting Files in this Example
+
+- `infra/bin/lambda-cache-aside.ts` - this is the CDK stack that defines the Lambda function its associated resources. It uses the `RustFunction` construct from the `cargo-lambda-cdk` package.
+- `rust/get-lambda/Cargo.toml` - this is the Cargo.toml file for the Lambda function. It includes the `lambda_runtime`crate as a dependency; this makes it easy to write Lambda functions in Rust
+- `rust/get-lambda/src/main.rs` - this is the Rust code for the Lambda function. It uses the AWS `lambda_runtime` crate to implement the `main` function in a way that is compatible with AWS's provided Amazon Linux runtimes.
+
+----------------------------------------------------------------------------------------
+For more info, visit our website at [https://gomomento.com](https://gomomento.com)!

example/aws/cache-aside-dsql-lambda/infra/bin/lambda-cache-aside.ts

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+#!/usr/bin/env node
+
+import * as cdk from 'aws-cdk-lib';
+import { LambdaCacheAsideStack } from '../lib/lambda-cache-aside-stack';
+
+const app = new cdk.App();
+new LambdaCacheAsideStack(app, 'LambdaCacheAsideDSQLStack', {
+    env: {
+        region: "us-east-1"
+    }
+});

example/aws/cache-aside-dsql-lambda/infra/cdk.json

@@ -0,0 +1,80 @@
+{
+  "app": "npx ts-node --prefer-ts-exts bin/lambda-cache-aside.ts",
+  "watch": {
+    "include": [
+      "**"
+    ],
+    "exclude": [
+      "README.md",
+      "cdk*.json",
+      "**/*.d.ts",
+      "**/*.js",
+      "tsconfig.json",
+      "package*.json",
+      "yarn.lock",
+      "node_modules",
+      "test"
+    ]
+  },
+  "context": {
+    "@aws-cdk/aws-lambda:recognizeLayerVersion": true,
+    "@aws-cdk/core:checkSecretUsage": true,
+    "@aws-cdk/core:target-partitions": [
+      "aws",
+      "aws-cn"
+    ],
+    "@aws-cdk-containers/ecs-service-extensions:enableDefaultLogDriver": true,
+    "@aws-cdk/aws-ec2:uniqueImdsv2TemplateName": true,
+    "@aws-cdk/aws-ecs:arnFormatIncludesClusterName": true,
+    "@aws-cdk/aws-iam:minimizePolicies": true,
+    "@aws-cdk/core:validateSnapshotRemovalPolicy": true,
+    "@aws-cdk/aws-codepipeline:crossAccountKeyAliasStackSafeResourceName": true,
+    "@aws-cdk/aws-s3:createDefaultLoggingPolicy": true,
+    "@aws-cdk/aws-sns-subscriptions:restrictSqsDescryption": true,
+    "@aws-cdk/aws-apigateway:disableCloudWatchRole": true,
+    "@aws-cdk/core:enablePartitionLiterals": true,
+    "@aws-cdk/aws-events:eventsTargetQueueSameAccount": true,
+    "@aws-cdk/aws-ecs:disableExplicitDeploymentControllerForCircuitBreaker": true,
+    "@aws-cdk/aws-iam:importedRoleStackSafeDefaultPolicyName": true,
+    "@aws-cdk/aws-s3:serverAccessLogsUseBucketPolicy": true,
+    "@aws-cdk/aws-route53-patters:useCertificate": true,
+    "@aws-cdk/customresources:installLatestAwsSdkDefault": false,
+    "@aws-cdk/aws-rds:databaseProxyUniqueResourceName": true,
+    "@aws-cdk/aws-codedeploy:removeAlarmsFromDeploymentGroup": true,
+    "@aws-cdk/aws-apigateway:authorizerChangeDeploymentLogicalId": true,
+    "@aws-cdk/aws-ec2:launchTemplateDefaultUserData": true,
+    "@aws-cdk/aws-secretsmanager:useAttachedSecretResourcePolicyForSecretTargetAttachments": true,
+    "@aws-cdk/aws-redshift:columnId": true,
+    "@aws-cdk/aws-stepfunctions-tasks:enableEmrServicePolicyV2": true,
+    "@aws-cdk/aws-ec2:restrictDefaultSecurityGroup": true,
+    "@aws-cdk/aws-apigateway:requestValidatorUniqueId": true,
+    "@aws-cdk/aws-kms:aliasNameRef": true,
+    "@aws-cdk/aws-autoscaling:generateLaunchTemplateInsteadOfLaunchConfig": true,
+    "@aws-cdk/core:includePrefixInUniqueNameGeneration": true,
+    "@aws-cdk/aws-efs:denyAnonymousAccess": true,
+    "@aws-cdk/aws-opensearchservice:enableOpensearchMultiAzWithStandby": true,
+    "@aws-cdk/aws-lambda-nodejs:useLatestRuntimeVersion": true,
+    "@aws-cdk/aws-efs:mountTargetOrderInsensitiveLogicalId": true,
+    "@aws-cdk/aws-rds:auroraClusterChangeScopeOfInstanceParameterGroupWithEachParameters": true,
+    "@aws-cdk/aws-appsync:useArnForSourceApiAssociationIdentifier": true,
+    "@aws-cdk/aws-rds:preventRenderingDeprecatedCredentials": true,
+    "@aws-cdk/aws-codepipeline-actions:useNewDefaultBranchForCodeCommitSource": true,
+    "@aws-cdk/aws-cloudwatch-actions:changeLambdaPermissionLogicalIdForLambdaAction": true,
+    "@aws-cdk/aws-codepipeline:crossAccountKeysDefaultValueToFalse": true,
+    "@aws-cdk/aws-codepipeline:defaultPipelineTypeToV2": true,
+    "@aws-cdk/aws-kms:reduceCrossAccountRegionPolicyScope": true,
+    "@aws-cdk/aws-eks:nodegroupNameAttribute": true,
+    "@aws-cdk/aws-ec2:ebsDefaultGp3Volume": true,
+    "@aws-cdk/aws-ecs:removeDefaultDeploymentAlarm": true,
+    "@aws-cdk/custom-resources:logApiResponseDataPropertyTrueDefault": false,
+    "@aws-cdk/aws-s3:keepNotificationInImportedBucket": false,
+    "@aws-cdk/aws-ecs:reduceEc2FargateCloudWatchPermissions": true,
+    "@aws-cdk/aws-dynamodb:resourcePolicyPerReplica": true,
+    "@aws-cdk/aws-ec2:ec2SumTImeoutEnabled": true,
+    "@aws-cdk/aws-appsync:appSyncGraphQLAPIScopeLambdaPermission": true,
+    "@aws-cdk/aws-rds:setCorrectValueForDatabaseInstanceReadReplicaInstanceResourceId": true,
+    "@aws-cdk/core:cfnIncludeRejectComplexResourceUpdateCreatePolicyIntrinsics": true,
+    "@aws-cdk/aws-lambda-nodejs:sdkV3ExcludeSmithyPackages": true,
+    "@aws-cdk/aws-stepfunctions-tasks:fixRunEcsTaskPolicy": true
+  }
+}

example/aws/cache-aside-dsql-lambda/infra/jest.config.js

@@ -0,0 +1,8 @@
+module.exports = {
+  testEnvironment: 'node',
+  roots: ['<rootDir>/test'],
+  testMatch: ['**/*.test.ts'],
+  transform: {
+    '^.+\\.tsx?$': 'ts-jest'
+  }
+};

example/aws/cache-aside-dsql-lambda/infra/lib/constructs/lambda-construct.ts

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+import { Effect, PolicyStatement } from "aws-cdk-lib/aws-iam";
+import { Architecture, FunctionUrlAuthType, LayerVersion } from "aws-cdk-lib/aws-lambda";
+import { RustFunction } from "cargo-lambda-cdk";
+import { Construct } from "constructs"
+
+export class LambdaConstruct extends Construct {
+  constructor(scope: Construct, id: string) {
+    super(scope, id);
+
+    const select = new RustFunction(scope, 'SelectFunction', {
+      architecture: Architecture.ARM_64,
+      functionName: "cacheable-table-select-dsql",
+      manifestPath: '../rust/get-lambda',
+      memorySize: 256,
+      environment: {
+        CLUSTER_ENDPOINT: process.env.CLUSTER_ENDPOINT!,
+        MOMENTO_API_KEY: process.env.MOMENTO_API_KEY!,
+        CACHE_NAME: "CacheableTable",
+        RUST_LOG: 'info',
+      },
+    })
+
+    select.addToRolePolicy(new PolicyStatement({
+      effect: Effect.ALLOW,
+      actions: ["dsql:*"],
+      resources: ["*"]
+    }))
+
+    select.addFunctionUrl({
+      authType: FunctionUrlAuthType.NONE,
+      cors: {
+        allowedOrigins: ["*"]
+      }
+    })
+
+
+  }
+}

example/aws/cache-aside-dsql-lambda/infra/lib/lambda-cache-aside-stack.ts

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+import * as cdk from 'aws-cdk-lib';
+import { Construct } from 'constructs';
+import { LambdaConstruct } from './constructs/lambda-construct';
+
+export class LambdaCacheAsideStack extends cdk.Stack {
+  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    new LambdaConstruct(this, 'LambdaConstruct');
+
+  }
+}