support resolver/relay target as thunk (#568)

* support resolver/relay target as thunk

* fix lint

* rename targetResolver to targetMaybeThunk

Author: mickhansen

src/relay.js

@@ -7,8 +7,7 @@ import {
 } from 'graphql-relay';
 
 import {
-  GraphQLList,
-  GraphQLEnumType
+  GraphQLList
 } from 'graphql';
 
 import {
@@ -105,7 +104,7 @@ export function nodeType(connectionType) {
 export function sequelizeConnection({
   name,
   nodeType,
-  target,
+  target: targetMaybeThunk,
   orderBy: orderByEnum,
   before,
   after,
@@ -123,29 +122,22 @@ export function sequelizeConnection({
     edgeFields
   });
 
-  const model = target.target ? target.target : target;
   const SEPERATOR = '$';
   const PREFIX = 'arrayconnection' + SEPERATOR;
 
-  if (orderByEnum === undefined) {
-    orderByEnum = new GraphQLEnumType({
-      name: name + 'ConnectionOrder',
-      values: {
-        ID: {value: [model.primaryKeyAttribute, 'ASC']}
-      }
-    });
-  }
-
   before = before || ((options) => options);
   after = after || ((result) => result);
 
   let $connectionArgs = {
-    ...connectionArgs,
-    orderBy: {
-      type: new GraphQLList(orderByEnum)
-    }
+    ...connectionArgs
   };
 
+  if (orderByEnum) {
+    $connectionArgs.orderBy = {
+      type: new GraphQLList(orderByEnum)
+    };
+  }
+
   let orderByAttribute = function (orderAttr, {source, args, context, info}) {
     return typeof orderAttr === 'function' ? orderAttr(source, args, context, info) : orderAttr;
   };
@@ -166,7 +158,7 @@ export function sequelizeConnection({
    * @return {String}          The Base64 encoded cursor string
    */
   let toCursor = function (item, index) {
-    let id = item.get(model.primaryKeyAttribute);
+    let id = item.get(item.Model.primaryKeyAttribute);
     return base64(PREFIX + id + SEPERATOR + index);
   };
 
@@ -189,6 +181,8 @@ export function sequelizeConnection({
   let argsToWhere = function (args) {
     let result = {};
 
+    if (where === undefined) return result;
+
     _.each(args, (value, key) => {
       if (key in $connectionArgs) return;
       _.assign(result, where(key, value, result));
@@ -213,16 +207,21 @@ export function sequelizeConnection({
     };
   };
 
-  let $resolver = require('./resolver')(target, {
+  let $resolver = require('./resolver')(targetMaybeThunk, {
     handleConnection: false,
     list: true,
     before: function (options, args, context, info) {
+      const target = info.target;
+      const model = target.target ? target.target : target;
+
       if (args.first || args.last) {
         options.limit = parseInt(args.first || args.last, 10);
       }
       if (!args.orderBy) {
-        args.orderBy = [orderByEnum._values[0].value];
-      } else if (typeof args.orderBy === 'string') {
+        args.orderBy = [
+          [model.primaryKeyAttribute, 'ASC']
+        ];
+      } else if (orderByEnum && typeof args.orderBy === 'string') {
         args.orderBy = [orderByEnum._nameLookup[args.orderBy].value];
       }
 
@@ -275,6 +274,7 @@ export function sequelizeConnection({
     after: async function (values, args, context, info) {
       const {
         source,
+        target
       } = info;
 
       var cursor = null;

src/resolver.js

@@ -15,31 +15,32 @@ function whereQueryVarsToValues(o, vals) {
   });
 }
 
-function resolverFactory(target, options = {}) {
-  var resolver
-    , targetAttributes
-    , isModel = !!target.getTableName
-    , isAssociation = !!target.associationType
-    , association = isAssociation && target
-    , model = isAssociation && target.target || isModel && target
-    , contextToOptions = _.assign({}, resolverFactory.contextToOptions, options.contextToOptions);
-
-  targetAttributes = Object.keys(model.rawAttributes);
+function resolverFactory(targetMaybeThunk, options = {}) {
+  const contextToOptions = _.assign({}, resolverFactory.contextToOptions, options.contextToOptions);
 
   invariant(options.include === undefined, 'Include support has been removed in favor of dataloader batching');
   if (options.before === undefined) options.before = (options) => options;
   if (options.after === undefined) options.after = (result) => result;
   if (options.handleConnection === undefined) options.handleConnection = true;
 
-  resolver = function (source, args, context, info) {
-    var type = info.returnType
-      , list = options.list || type instanceof GraphQLList
+  return async function (source, args, context, info) {
+    let target = typeof targetMaybeThunk === 'function' && targetMaybeThunk.findAndCountAll === undefined ?
+                 await Promise.resolve(targetMaybeThunk(source, args, context, info)) : targetMaybeThunk
+      , isModel = !!target.getTableName
+      , isAssociation = !!target.associationType
+      , association = isAssociation && target
+      , model = isAssociation && target.target || isModel && target
+      , type = info.returnType
+      , list = options.list || type instanceof GraphQLList;
+
+    let targetAttributes = Object.keys(model.rawAttributes)
       , findOptions = argsToFindOptions(args, targetAttributes);
 
     info = {
       ...info,
       type: type,
-      source: source
+      source: source,
+      target: target
     };
 
     context = context || {};
@@ -92,8 +93,6 @@ function resolverFactory(target, options = {}) {
       return options.after(result, args, context, info);
     });
   };
-
-  return resolver;
 }
 
 resolverFactory.contextToOptions = {};

test/integration/relay/connection.test.js

@@ -111,7 +111,7 @@ describe('relay', function () {
       this.userTaskConnection = sequelizeConnection({
         name: 'userTask',
         nodeType: this.taskType,
-        target: this.User.Tasks,
+        target: () => this.User.Tasks,
         orderBy: new GraphQLEnumType({
           name: this.User.name + this.Task.name + 'ConnectionOrder',
           values: {
@@ -507,7 +507,7 @@ describe('relay', function () {
     });
 
     it('should handle orderBy function case', async function () {
-      await graphql(this.schema, `
+      const result = await graphql(this.schema, `
         {
           user(id: ${this.userA.id}) {
             projects(first: 1) {
@@ -529,6 +529,8 @@ describe('relay', function () {
         }
       `, null, {});
 
+      if (result.errors) throw new Error(result.errors[0]);
+
       expect(this.projectOrderSpy).to.have.been.calledOnce;
       expect(this.projectOrderSpy.alwaysCalledWithMatch({}, { first: 5 })).to.be.ok;
     });

test/integration/resolver.test.js

@@ -166,7 +166,7 @@ describe('resolver', function () {
               type: GraphQLInt
             }
           },
-          resolve: resolver(User.Tasks, {
+          resolve: resolver(() => User.Tasks, {
             before: function (options, args) {
               if (args.first) {
                 options.order = options.order || [];

test/unit/relay/connection.test.js

@@ -89,7 +89,7 @@ describe('relay', function () {
     });
 
     it('passes context, root and info to before', async function () {
-      await graphql(this.schema, `
+      const result = await graphql(this.schema, `
         query {
           viewer {
             tasks {
@@ -105,10 +105,13 @@ describe('relay', function () {
         viewer: this.viewer
       });
 
+      if (result.errors) throw new Error(result.errors[0]);
+
+      expect(this.beforeSpy).to.have.been.calledOnce;
       expect(this.beforeSpy).to.have.been.calledWithMatch(
         sinon.match.any,
         sinon.match({
-          orderBy: sinon.match.any
+          first: sinon.match.any
         }),
         sinon.match({
           viewer: {
@@ -125,7 +128,7 @@ describe('relay', function () {
           fullCount: sinon.match.number
         }),
         sinon.match({
-          orderBy: sinon.match.any
+          first: sinon.match.any
         }),
         sinon.match({
           viewer: {