Merge pull request #188 from guardian/jw-provide-sensible-defaults

Provide sensible defaults for GuLambda memorySize and timeout

src/constructs/lambda/__snapshots__/lambda.test.ts.snap

@@ -84,6 +84,7 @@ Object {
           "S3Key": "folder/to/key",
         },
         "Handler": "handler.ts",
+        "MemorySize": 512,
         "Role": Object {
           "Fn::GetAtt": Array [
             "lambdaServiceRole494E4CA6",
@@ -109,6 +110,7 @@ Object {
             },
           },
         ],
+        "Timeout": 30,
       },
       "Type": "AWS::Lambda::Function",
     },

src/constructs/lambda/lambda.test.ts

@@ -143,4 +143,62 @@ describe("The GuLambdaFunction class", () => {
       },
     });
   });
+
+  it("should use the memorySize provided via props when it is defined", () => {
+    const stack = simpleGuStackForTesting();
+
+    new GuLambdaFunction(stack, "lambda", {
+      code: { bucket: "bucket1", key: "folder/to/key" },
+      handler: "handler.ts",
+      runtime: Runtime.JAVA_8,
+      memorySize: 2048,
+    });
+
+    expect(stack).toHaveResource("AWS::Lambda::Function", {
+      MemorySize: 2048,
+    });
+  });
+
+  it("should add a sensible default memorySize if none is provided", () => {
+    const stack = simpleGuStackForTesting();
+
+    new GuLambdaFunction(stack, "lambda", {
+      code: { bucket: "bucket1", key: "folder/to/key" },
+      handler: "handler.ts",
+      runtime: Runtime.JAVA_8,
+    });
+
+    expect(stack).toHaveResource("AWS::Lambda::Function", {
+      MemorySize: 1024,
+    });
+  });
+
+  it("should use the timeout provided via props when it is defined", () => {
+    const stack = simpleGuStackForTesting();
+
+    new GuLambdaFunction(stack, "lambda", {
+      code: { bucket: "bucket1", key: "folder/to/key" },
+      handler: "handler.ts",
+      runtime: Runtime.JAVA_8,
+      timeout: Duration.seconds(60),
+    });
+
+    expect(stack).toHaveResource("AWS::Lambda::Function", {
+      Timeout: 60,
+    });
+  });
+
+  it("should add a sensible default timeout if none is provided", () => {
+    const stack = simpleGuStackForTesting();
+
+    new GuLambdaFunction(stack, "lambda", {
+      code: { bucket: "bucket1", key: "folder/to/key" },
+      handler: "handler.ts",
+      runtime: Runtime.JAVA_8,
+    });
+
+    expect(stack).toHaveResource("AWS::Lambda::Function", {
+      Timeout: 30,
+    });
+  });
 });

src/constructs/lambda/lambda.ts

@@ -3,9 +3,10 @@ import { LambdaRestApi } from "@aws-cdk/aws-apigateway";
 import type { Schedule } from "@aws-cdk/aws-events";
 import { Rule } from "@aws-cdk/aws-events";
 import { LambdaFunction } from "@aws-cdk/aws-events-targets";
-import { Code, Function } from "@aws-cdk/aws-lambda";
-import type { FunctionProps } from "@aws-cdk/aws-lambda";
+import { Code, Function, RuntimeFamily } from "@aws-cdk/aws-lambda";
+import type { FunctionProps, Runtime } from "@aws-cdk/aws-lambda";
 import { Bucket } from "@aws-cdk/aws-s3";
+import { Duration } from "@aws-cdk/core";
 import type { GuStack } from "../core";
 
 interface ApiProps extends Omit<LambdaRestApiProps, "handler"> {
@@ -21,12 +22,27 @@ interface GuFunctionProps extends Omit<FunctionProps, "code"> {
   apis?: ApiProps[];
 }
 
+function defaultMemorySize(runtime: Runtime, memorySize?: number): number {
+  if (memorySize) {
+    return memorySize;
+  } else {
+    switch (runtime.family) {
+      case RuntimeFamily.JAVA:
+        return 1024;
+      default:
+        return 512;
+    }
+  }
+}
+
 export class GuLambdaFunction extends Function {
   constructor(scope: GuStack, id: string, props: GuFunctionProps) {
     const bucket = Bucket.fromBucketName(scope, `${id}-bucket`, props.code.bucket);
     const code = Code.fromBucket(bucket, props.code.key);
     super(scope, id, {
       ...props,
+      memorySize: defaultMemorySize(props.runtime, props.memorySize),
+      timeout: props.timeout ?? Duration.seconds(30),
       code,
     });