feat: configurable payload limit using cds.server.body_parser.limit (#177)

Author: schwma

CHANGELOG.md

@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Support for configuring request payload limit using global flag `cds.server.body_parser.limit`
+
 ### Changed
 
 - To improve performance, binary payloads are no longer validated to check if they are properly base64 or base64url encoded

lib/GraphQLAdapter.js

@@ -20,7 +20,7 @@ function GraphQLAdapter(options) {
     : defaultErrorFormatter
 
   router
-    .use(express.json()) //> required by logger below
+    .use(express.json({ ...cds.env.server.body_parser })) //> required by logger below
     .use(queryLogger)
 
   if (options.graphiql) router.use(graphiql)

package.json

@@ -40,10 +40,10 @@
   },
   "devDependencies": {
     "@cap-js/graphql": "file:.",
+    "@cap-js/sqlite": "^1",
     "axios": "^1",
     "express": "^4.17.1",
     "jest": "^29.3.1",
-    "semver": "^7.4.0",
-    "@cap-js/sqlite": "^1"
+    "semver": "^7.4.0"
   }
 }

test/resources/bookshop/package.json

@@ -10,6 +10,7 @@
     "index.js"
   ],
   "dependencies": {
+    "@cap-js/graphql": "*",
     "@sap/cds": ">=5.9",
     "express": "^4.17.1"
   },

test/resources/custom-handlers/package.json

@@ -1,4 +1,8 @@
 {
+  "Note: Programmatic configuration of GraphQL protocol adapter in server.js": "",
+  "__dependencies": {
+    "@cap-js/graphql": "*"
+  },
   "devDependencies": {
     "@cap-js/sqlite": "*"
   }

test/resources/types/package.json

@@ -1,5 +1,15 @@
 {
   "dependencies": {
+    "@cap-js/graphql": "*"
+  },
+  "devDependencies": {
     "@cap-js/sqlite": "*"
+  },
+  "cds": {
+    "server": {
+      "body_parser": {
+        "limit": "110KB"
+      }
+    }
   }
 }

test/resources/types/server.js

@@ -1,13 +1,19 @@
+const consumers = require('node:stream/consumers')
+
 const { gql } = require('../util')
 
 const _toBase64Url = value => value.replace(/\//g, '_').replace(/\+/g, '-')
 
-const _getTestBuffer = length => {
-  const testString = 'Test String! '
-  let string = testString.repeat(Math.ceil(length / testString.length)).slice(0, length)
-  return Buffer.from(string)
+const _getTestString = length => {
+  const testString = 'This is a test string! '
+  return testString.repeat(Math.ceil(length / testString.length)).slice(0, length)
 }
 
+const _getTestBuffer = length => Buffer.from(_getTestString(length))
+
+// e.g. base64 string with length 96 -> requires buffer with length 72
+const _neededBufferLengthForBase64StringWithLength = length => Math.ceil((length * 6) / 8)
+
 const _getMutationForFieldWithLiteralValue = (field, value, quoted) => ({
   query: gql`
     mutation {
@@ -48,9 +54,7 @@ describe('graphql - types parsing and validation', () => {
   // Prevent axios from throwing errors for non 2xx status codes
   axios.defaults.validateStatus = false
 
-  beforeEach(async () => {
-    await data.reset()
-  })
+  beforeEach(data.reset)
 
   describe('cds.Binary', () => {
     const field = 'myBinary'
@@ -1002,12 +1006,9 @@ describe('graphql - types parsing and validation', () => {
   })
 
   // Note: maps to same type as cds.Binary
-  // REVISIT: express-graphql limits request body size to 100kb by default:
-  // - https://github.com/graphql/express-graphql/issues/346
-  // - https://github.com/graphql/express-graphql/blob/28e4c2924ea6984bf918465cefdadae340d8780e/src/parseBody.ts#L96
-  describe.skip('cds.LargeBinary', () => {
+  describe('cds.LargeBinary', () => {
     const field = 'myLargeBinary'
-    const buffer = _getTestBuffer(500000) // 500 KB
+    const buffer = _getTestBuffer(_neededBufferLengthForBase64StringWithLength(105000)) // 105 KB as base64 string
 
     describe('input literal', () => {
       test('cds.LargeBinary is correctly parsed from large input literal base64 encoded string value', async () => {
@@ -1018,7 +1019,8 @@ describe('graphql - types parsing and validation', () => {
         expect(response.data).toEqual({ data })
 
         const result = await SELECT.one.from('sap.cds.graphql.types.MyEntity').columns(field)
-        expect(result[field]).toEqual(buffer)
+        const bufferFromDB = await consumers.buffer(result[field])
+        expect(bufferFromDB).toEqual(buffer)
       })
 
       test('cds.LargeBinary is correctly parsed from large input literal base64url encoded string value', async () => {
@@ -1029,7 +1031,8 @@ describe('graphql - types parsing and validation', () => {
         expect(response.data).toEqual({ data })
 
         const result = await SELECT.one.from('sap.cds.graphql.types.MyEntity').columns(field)
-        expect(result[field]).toEqual(buffer)
+        const bufferFromDB = await consumers.buffer(result[field])
+        expect(bufferFromDB).toEqual(buffer)
       })
     })
 
@@ -1042,7 +1045,8 @@ describe('graphql - types parsing and validation', () => {
         expect(response.data).toEqual({ data })
 
         const result = await SELECT.one.from('sap.cds.graphql.types.MyEntity').columns(field)
-        expect(result[field]).toEqual(buffer)
+        const bufferFromDB = await consumers.buffer(result[field])
+        expect(bufferFromDB).toEqual(buffer)
       })
 
       test('cds.LargeBinary is correctly parsed from large variable base64url encoded string value', async () => {
@@ -1053,18 +1057,16 @@ describe('graphql - types parsing and validation', () => {
         expect(response.data).toEqual({ data })
 
         const result = await SELECT.one.from('sap.cds.graphql.types.MyEntity').columns(field)
-        expect(result[field]).toEqual(buffer)
+        const bufferFromDB = await consumers.buffer(result[field])
+        expect(bufferFromDB).toEqual(buffer)
       })
     })
   })
 
   // Note: maps to same type as cds.String
-  // REVISIT: express-graphql limits request body size to 100kb by default:
-  // - https://github.com/graphql/express-graphql/issues/346
-  // - https://github.com/graphql/express-graphql/blob/28e4c2924ea6984bf918465cefdadae340d8780e/src/parseBody.ts#L96
-  describe.skip('cds.LargeString', () => {
+  describe('cds.LargeString', () => {
     const field = 'myLargeString'
-    const value = 'This is a test string! '.repeat(100000)
+    const value = _getTestString(105000) // 105 KB
 
     test('cds.LargeString is correctly parsed from input literal', async () => {
       const body = _getMutationForFieldWithLiteralValue(field, value, true)