fix: pass object and list arguments of a nested field to the subgraph

lib/utils.js

@@ -1,5 +1,7 @@
 'use strict'
 
+const { valueFromASTUntyped } = require('graphql')
+
 function defaultOnError (error) {
   throw error
 }
@@ -167,7 +169,8 @@ function collectNodeArgs (nodeArguments, info, types) {
     const node = nodeArguments[i]
     const name = node.name.value
     if (node.value.kind !== 'Variable') {
-      args[name] = node.value.value
+      // object and list literals have no .value, and may hold variables
+      args[name] = valueFromASTUntyped(node.value, info?.variableValues)
       continue
     }
     args[name] = collectVariableArg(node.value, info, types)

test/nested-args.test.js

@@ -0,0 +1,147 @@
+'use strict'
+
+const assert = require('node:assert')
+const { test } = require('node:test')
+
+const {
+  createComposerService,
+  createGraphqlServices,
+  graphqlRequest
+} = require('./helper')
+const { compose } = require('../lib')
+
+const artists = [
+  { id: '101', name: 'Nolan' },
+  { id: '102', name: 'Benigni' },
+  { id: '201', name: 'Pavarotti' }
+]
+
+const tags = [
+  { id: '1', artistId: '101', tag: 'visual', score: 3 },
+  { id: '2', artistId: '102', tag: 'visual', score: 1 },
+  { id: '3', artistId: '101', tag: 'sound', score: 2 }
+]
+
+const schema = `
+  enum OrderDirection { ASC DESC }
+
+  input IdCondition { eq: ID, in: [ID] }
+  input TagsWhere { id: IdCondition, tag: String }
+  input TagsOrderBy { field: String!, direction: OrderDirection! }
+
+  type Tag { id: ID! tag: String! }
+  type Artist { id: ID! name: String! tags(where: TagsWhere, orderBy: [TagsOrderBy], limit: Int): [Tag] }
+
+  type Query { artists: [Artist] }
+`
+
+function matches (tag, where) {
+  if (!where) { return true }
+  if (where.id?.eq !== undefined && tag.id !== where.id.eq) { return false }
+  if (where.id?.in !== undefined && !where.id.in.includes(tag.id)) { return false }
+  if (where.tag !== undefined && tag.tag !== where.tag) { return false }
+  return true
+}
+
+const resolvers = {
+  Query: {
+    artists: () => artists
+  },
+  Artist: {
+    tags: (artist, { where, orderBy, limit }) => {
+      let result = tags.filter(t => t.artistId === artist.id && matches(t, where))
+      for (const { field, direction } of orderBy ?? []) {
+        const sign = direction === 'ASC' ? 1 : -1
+        result = result.toSorted((a, b) => sign * (a[field] - b[field]))
+      }
+      return limit === undefined ? result : result.slice(0, limit)
+    }
+  }
+}
+
+async function setup (t) {
+  const services = await createGraphqlServices(t, [{
+    name: 'artists-subgraph',
+    mercurius: { schema, resolvers },
+    listen: true
+  }])
+
+  const options = {
+    subgraphs: services.map(service => ({
+      name: service.name,
+      server: { host: service.host }
+    }))
+  }
+
+  const { service } = await createComposerService(t, { compose, options })
+  return service
+}
+
+test('should pass an object argument of a nested field to the subgraph', async (t) => {
+  const service = await setup(t)
+
+  const query = '{ artists { id tags(where: { id: { eq: "1" } }) { id } } }'
+  const result = await graphqlRequest(service, query)
+
+  assert.deepStrictEqual(result, {
+    artists: [
+      { id: '101', tags: [{ id: '1' }] },
+      { id: '102', tags: [] },
+      { id: '201', tags: [] }
+    ]
+  })
+})
+
+test('should pass list, enum and int arguments of a nested field to the subgraph', async (t) => {
+  const service = await setup(t)
+
+  const query = `{
+    artists {
+      id
+      tags(where: { id: { in: ["1", "2", "3"] } }, orderBy: [{ field: "score", direction: ASC }], limit: 1) { id }
+    }
+  }`
+  const result = await graphqlRequest(service, query)
+
+  assert.deepStrictEqual(result, {
+    artists: [
+      { id: '101', tags: [{ id: '3' }] },
+      { id: '102', tags: [{ id: '2' }] },
+      { id: '201', tags: [] }
+    ]
+  })
+})
+
+test('should pass variables inside an object argument of a nested field to the subgraph', async (t) => {
+  const service = await setup(t)
+
+  const query = `query ($id: ID, $tag: String) {
+    artists { id tags(where: { id: { eq: $id }, tag: $tag }) { id } }
+  }`
+  const result = await graphqlRequest(service, query, { id: '3', tag: 'sound' })
+
+  assert.deepStrictEqual(result, {
+    artists: [
+      { id: '101', tags: [{ id: '3' }] },
+      { id: '102', tags: [] },
+      { id: '201', tags: [] }
+    ]
+  })
+})
+
+test('should pass an object variable as argument of a nested field to the subgraph', async (t) => {
+  const service = await setup(t)
+
+  const query = `query ($where: TagsWhere) {
+    artists { id tags(where: $where) { id } }
+  }`
+  const result = await graphqlRequest(service, query, { where: { tag: 'visual' } })
+
+  assert.deepStrictEqual(result, {
+    artists: [
+      { id: '101', tags: [{ id: '1' }] },
+      { id: '102', tags: [{ id: '2' }] },
+      { id: '201', tags: [] }
+    ]
+  })
+})