Add optional cache max value size limit configuration (#13871)

Resolves #13708

api/src/env.ts

@@ -74,6 +74,7 @@ const allowedEnvironmentVars = [
 	'CACHE_REDIS_PORT',
 	'CACHE_REDIS_PASSWORD',
 	'CACHE_MEMCACHE',
+	'CACHE_VALUE_MAX_SIZE',
 	// storage
 	'STORAGE_LOCATIONS',
 	'STORAGE_.+_DRIVER',
@@ -206,6 +207,7 @@ const defaults: Record<string, any> = {
 	CACHE_CONTROL_S_MAXAGE: '0',
 	CACHE_SCHEMA: true,
 	CACHE_PERMISSIONS: true,
+	CACHE_VALUE_MAX_SIZE: false,
 
 	AUTH_PROVIDERS: '',
 	AUTH_DISABLE_DEFAULT: false,

api/src/middleware/respond.ts

@@ -8,16 +8,27 @@ import { getCacheControlHeader } from '../utils/get-cache-headers';
 import logger from '../logger';
 import { ExportService } from '../services';
 import { getDateFormatted } from '../utils/get-date-formatted';
+import { stringByteSize } from '../utils/get-string-byte-size';
+import { parse as parseBytesConfiguration } from 'bytes';
 
 export const respond: RequestHandler = asyncHandler(async (req, res) => {
 	const { cache } = getCache();
 
+	let exceedsMaxSize = false;
+
+	if (env.CACHE_VALUE_MAX_SIZE !== false) {
+		const valueSize = stringByteSize(JSON.stringify(res.locals.payload));
+		const maxSize = parseBytesConfiguration(env.CACHE_VALUE_MAX_SIZE);
+		exceedsMaxSize = valueSize > maxSize;
+	}
+
 	if (
 		req.method.toLowerCase() === 'get' &&
 		env.CACHE_ENABLED === true &&
 		cache &&
 		!req.sanitizedQuery.export &&
-		res.locals.cache !== false
+		res.locals.cache !== false &&
+		exceedsMaxSize === false
 	) {
 		const key = getCacheKey(req);
 

api/src/utils/get-string-byte-size.ts

@@ -0,0 +1,6 @@
+/**
+ * Returns the byte size for a given input string
+ */
+export function stringByteSize(string: string): number {
+	return Buffer.byteLength(string, 'utf-8');
+}