feat: add context to default handler and allow custom handler

BREAKING CHANGES: default handlers now have a context argument

src/Binding.ts

@@ -5,33 +5,35 @@ import { delegateToSchema } from 'graphql-tools'
 import { makeProxy, makeSubscriptionProxy } from './proxy'
 import { QueryMap, BindingOptions, FragmentReplacements, SubscriptionMap, Operation } from './types'
 
-export class Binding {
-  query: QueryMap
-  mutation: QueryMap
-  subscription: SubscriptionMap
+export class Binding<TQueryMap extends object = QueryMap, TSubscriptionMap extends object = SubscriptionMap> {
+  query: TQueryMap
+  mutation: TQueryMap
+  subscription: TSubscriptionMap
   schema: GraphQLSchema
   before: () => void
 
   private fragmentReplacements: FragmentReplacements
 
-  constructor({ schema, fragmentReplacements, before }: BindingOptions) {
+  constructor({ schema, fragmentReplacements, before, handler }: BindingOptions) {
     this.fragmentReplacements = fragmentReplacements || {}
     this.schema = schema
     this.before = before || (() => undefined)
 
-    this.query = makeProxy<QueryMap>({
+    this.query = makeProxy<TQueryMap>({
       schema: this.schema,
       fragmentReplacements: this.fragmentReplacements,
       operation: 'query',
-      before: this.before
+      before: this.before,
+      handler
     })
-    this.mutation = makeProxy<QueryMap>({
+    this.mutation = makeProxy<TQueryMap>({
       schema: this.schema,
       fragmentReplacements: this.fragmentReplacements,
       operation: 'mutation',
-      before: this.before
+      before: this.before,
+      handler
     })
-    this.subscription = makeSubscriptionProxy<SubscriptionMap>({
+    this.subscription = makeSubscriptionProxy<TSubscriptionMap>({
       schema: this.schema,
       fragmentReplacements: this.fragmentReplacements,
       before: this.before

src/handler.ts

@@ -15,6 +15,7 @@ export class Handler<T extends object> implements ProxyHandler<T> {
   get(target: T, rootFieldName: string) {
     return (
       args?: { [key: string]: any },
+      context?: { [key: string]: any },
       info?: GraphQLResolveInfo | string,
     ): Promise<ExecutionResult> => {
       this.before()
@@ -28,7 +29,7 @@ export class Handler<T extends object> implements ProxyHandler<T> {
         operation,
         rootFieldName,
         args || {},
-        {},
+        context || {},
         info,
       )
     }
@@ -45,6 +46,7 @@ export class SubscriptionHandler<T extends object> implements ProxyHandler<T> {
   get(target: T, rootFieldName: string) {
     return async (
       args?: { [key: string]: any },
+      context?: { [key: string]: any },
       infoOrQuery?: GraphQLResolveInfo | string,
     ): Promise<AsyncIterator<any>> => {
       this.before()
@@ -62,7 +64,7 @@ export class SubscriptionHandler<T extends object> implements ProxyHandler<T> {
         'subscription',
         rootFieldName,
         args || {},
-        {},
+        context || {},
         info,
       )
 

src/proxy.ts

@@ -7,15 +7,19 @@ export function makeProxy<T extends object = any>({
   fragmentReplacements,
   operation,
   before,
+  handler
 }: {
   schema: GraphQLSchema
   fragmentReplacements: FragmentReplacements
   operation: 'query' | 'mutation'
-  before: () => void
+  before: () => void,
+  handler?: { new<T extends object>(schema, fragmentReplacements, operation, before): ProxyHandler<T> }
 }): T {
   return new Proxy(
     {} as T,
-    new Handler<T>(schema, fragmentReplacements, operation, before),
+    handler
+      ? new handler<T>(schema, fragmentReplacements, operation, before)
+      : new Handler<T>(schema, fragmentReplacements, operation, before),
   )
 }
 

src/types.ts

@@ -10,14 +10,16 @@ export interface FragmentReplacements {
 
 export interface QueryMap {
   [rootField: string]: (
-    args?: any,
+    args?: { [key: string]: any },
+    context?: { [key: string]: any },
     info?: GraphQLResolveInfo | string,
   ) => Promise<any>
 }
 
 export interface SubscriptionMap {
   [rootField: string]: (
     args?: any,
+    context?: { [key: string]: any },
     info?: GraphQLResolveInfo | string,
   ) => AsyncIterator<any> | Promise<AsyncIterator<any>>
 }
@@ -26,4 +28,5 @@ export interface BindingOptions {
   fragmentReplacements?: FragmentReplacements
   schema: GraphQLSchema
   before?: () => void
+  handler?: any
 }