🤖 Merge PR DefinitelyTyped#73804 [aws-lambda] Update AttributeValue definition to be compatible with the one in @aws-sdk/client-dynamodb by @KuSh

Author: KuSh

types/aws-lambda/test/dynamodb-tests.ts

@@ -1,4 +1,4 @@
-import { DynamoDBBatchResponse, DynamoDBStreamEvent, DynamoDBStreamHandler } from "aws-lambda";
+import { DynamoDBBatchResponse, DynamoDBStreamEvent, DynamoDBStreamHandler, StreamRecord } from "aws-lambda";
 
 // TODO: Update test to read all event properties, and write all result
 //       properties, like the user will.
@@ -97,6 +97,17 @@ const event: DynamoDBStreamEvent = {
     ],
 };
 
+const keys: StreamRecord = {
+    Keys: {
+        // expect error when using multiple attributes in AttributeValue type
+        // @ts-expect-error
+        Id: {
+            N: "101",
+            S: "Extra",
+        },
+    },
+};
+
 const streamHandlerWithResponse: DynamoDBStreamHandler = async (event, context, callback) => {
     // Check result type
     let result: DynamoDBBatchResponse;

types/aws-lambda/trigger/dynamodb-stream.d.ts

@@ -3,19 +3,27 @@ import { Handler } from "../handler";
 // eslint-disable-next-line @typescript-eslint/no-invalid-void-type
 export type DynamoDBStreamHandler = Handler<DynamoDBStreamEvent, DynamoDBBatchResponse | void>;
 
+// eslint-disable-next-line @definitelytyped/strict-export-declare-modifiers, @definitelytyped/no-single-element-tuple-type
+type Merge<T> = [{ [K in keyof T]: T[K] }][number];
+
+// eslint-disable-next-line @definitelytyped/strict-export-declare-modifiers
+type ExclusivePropertyUnion<T, P = keyof T> = P extends any
+    ? Merge<{ [K in Extract<keyof T, P>]: T[K] } & { [K in Exclude<keyof T, P>]?: never }>
+    : never;
+
 // http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_streams_AttributeValue.html
-export interface AttributeValue {
-    B?: string | undefined;
-    BS?: string[] | undefined;
-    BOOL?: boolean | undefined;
-    L?: AttributeValue[] | undefined;
-    M?: { [id: string]: AttributeValue } | undefined;
-    N?: string | undefined;
-    NS?: string[] | undefined;
-    NULL?: boolean | undefined;
-    S?: string | undefined;
-    SS?: string[] | undefined;
-}
+export type AttributeValue = ExclusivePropertyUnion<{
+    B: string;
+    BOOL: boolean;
+    BS: string[];
+    L: AttributeValue[];
+    M: Record<string, AttributeValue>;
+    N: string;
+    NS: string[];
+    NULL: boolean;
+    S: string;
+    SS: string[];
+}>;
 
 // http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_streams_StreamRecord.html
 export interface StreamRecord {