KV: get bulk - add content too long error (#8808)

* KV: get bulk - add content too long error

* update changeset

* fix formatting

---------

Co-authored-by: talves <[email protected]>
Co-authored-by: Peter Bacon Darwin <[email protected]>

Author: teresalves

.changeset/common-worms-worry.md

@@ -0,0 +1,5 @@
+---
+"miniflare": patch
+---
+
+KV: improve error messages for bulk gets

packages/miniflare/src/workers/kv/constants.ts

@@ -7,6 +7,7 @@ export const KVLimits = {
 	MAX_VALUE_SIZE: 25 * 1024 * 1024 /* 25MiB */,
 	MAX_VALUE_SIZE_TEST: 1024 /* 1KiB */,
 	MAX_METADATA_SIZE: 1024 /* 1KiB */,
+	MAX_BULK_SIZE: 25 * 1024 * 1024 /* 25MiB */,
 } as const;
 
 export const KVParams = {

packages/miniflare/src/workers/kv/namespace.worker.ts

@@ -90,6 +90,7 @@ async function processKeyValue(
 	}
 
 	let val = null;
+	const size = decodedValue.length;
 	try {
 		val = !obj?.value
 			? null
@@ -99,16 +100,19 @@ async function processKeyValue(
 	} catch (err: any) {
 		throw new HttpError(
 			400,
-			"At least one of the requested keys corresponds to a non-JSON value"
+			`At least one of the requested keys corresponds to a non-${type} value`
 		);
 	}
 	if (val && withMetadata) {
-		return {
-			value: val,
-			metadata: obj?.metadata ?? null,
-		};
+		return [
+			{
+				value: val,
+				metadata: obj?.metadata ?? null,
+			},
+			size,
+		];
 	}
-	return val;
+	return [val, size];
 }
 
 export class KVNamespaceObject extends MiniflareDurableObject {
@@ -132,24 +136,35 @@ export class KVNamespaceObject extends MiniflareDurableObject {
 			const keys: string[] = parsedBody.keys;
 			const type = parsedBody?.type;
 			if (type && type !== "text" && type !== "json") {
-				return new Response(`Type ${type} is invalid`, { status: 400 });
+				return new Response("Bad Request", { status: 400 });
 			}
 			const obj: { [key: string]: any } = {};
 			if (keys.length > MAX_BULK_GET_KEYS) {
-				return new Response(`Accepting a max of 100 keys, got ${keys.length}`, {
+				return new Response("Bad Request", {
 					status: 400,
 				});
 			}
+			let totalBytes = 0;
 			for (const key of keys) {
 				validateGetOptions(key, { cacheTtl: parsedBody?.cacheTtl });
 				const entry = await this.storage.get(key);
-				const value = await processKeyValue(
+				const [value, size] = await processKeyValue(
 					entry,
 					parsedBody?.type,
 					parsedBody?.withMetadata
 				);
+				totalBytes += size;
 				obj[key] = value;
 			}
+			const maxValueSize = this.beingTested
+				? KVLimits.MAX_VALUE_SIZE_TEST
+				: KVLimits.MAX_BULK_SIZE;
+			if (totalBytes > maxValueSize) {
+				throw new HttpError(
+					413,
+					`Total size of request exceeds the limit of ${maxValueSize / 1024 / 1024}MB`
+				);
+			}
 
 			return new Response(JSON.stringify(obj));
 		}

packages/miniflare/test/plugins/kv/index.spec.ts

@@ -168,7 +168,7 @@ test("bulk get: request json type", async (t) => {
 	} catch (error: any) {
 		t.is(
 			error.message,
-			"KV GET_BULK failed: 400 At least one of the requested keys corresponds to a non-JSON value"
+			"KV GET_BULK failed: 400 At least one of the requested keys corresponds to a non-json value"
 		);
 	}
 });
@@ -224,6 +224,21 @@ test("bulk get: get with metadata for 404", async (t) => {
 	t.deepEqual(result, expectedResult);
 });
 
+test("bulk get: get over size limit", async (t) => {
+	const { kv } = t.context;
+	const bigValue = new Array(1024).fill("x").join("");
+	await kv.put("key1", bigValue);
+	await kv.put("key2", bigValue);
+	try {
+		await kv.getWithMetadata(["key1", "key2"]);
+	} catch (error: any) {
+		t.deepEqual(
+			error.message,
+			"KV GET_BULK failed: 413 Total size of request exceeds the limit of 0.0009765625MB" // 1024 Bytes for testing
+		);
+	}
+});
+
 test("get: returns null for non-existent keys", async (t) => {
 	const { kv } = t.context;
 	t.is(await kv.get("key"), null);