added eslint, nyc, reuse memoize commonly between resolver.memoize and directive

Author: tlivings

.eslintrc

@@ -0,0 +1,12 @@
+{
+  "extends": ["eslint:recommended"],
+  "parserOptions": {
+    "ecmaVersion": 2018,
+    "sourceType": "module"
+  },
+  "env": {
+    "browser": false,
+    "node": true,
+    "es6": true
+  }
+}

lib/directives.js

@@ -1,53 +1,20 @@
 'use strict';
 
 const { SchemaDirectiveVisitor } = require('graphql-tools');
-const debug = require('debug')('graphql-component:resolver');
+const Resolver = require('./resolvers');
+const debug = require('debug')('graphql-component:directive');
 
 const _cache = new WeakMap();
 
 class MemoizeDirective extends SchemaDirectiveVisitor {
   visitFieldDefinition(field) {
     const { resolve } = field;
-    
+    console.log(field);
     if (!resolve) {
       return;
     }
 
-    const memoize = function (resolve) {
-      return function (_, args, context, info) {
-        const key = JSON.stringify(args);
-        const { parentType } = info;
-        
-        let cached = _cache.get(context);
-
-        if (cached && cached[parentType] && cached[parentType][field.name] && cached[parentType][field.name][key]) {
-          debug(`return cached result of memoized ${parentType}.${field.name}`);
-          return cached[parentType][field.name][key];
-        }
-    
-        debug(`executing and caching memoized ${parentType}.${field.name}`);
-
-        if (!cached) {
-          cached = {};
-        }
-        if (!cached[parentType]) {
-          cached[parentType] = {};
-        }
-        if (!cached[parentType][field.name]) {
-          cached[parentType][field.name] = {};
-        }
-    
-        const result = resolve(_, args, context, info);
-
-        cached[parentType][field.name][key] = result;
-
-        _cache.set(context, cached);
-    
-        return result;
-      };
-    };
-
-    field.resolve = memoize(resolve);
+    field.resolve = Resolver.memoize(field.name, resolve);
 
     debug(`memoized ${field.name}`);
   }

lib/resolvers.js

@@ -15,8 +15,12 @@ const wrapResolvers = function (bind, resolvers = {}) {
       if (wrapped[name][resolverName]) {
         continue;
       }
-      
-      wrapped[name][resolverName] = ['Query', 'Mutation', 'Subscription'].indexOf(name) > -1 ? memoize(name, resolverName, func.bind(bind)) : func.bind(bind);
+      if (['Query', 'Mutation', 'Subscription'].indexOf(name) > -1) {
+        debug(`memoized ${name}.${resolverName}`);
+        wrapped[name][resolverName] = memoize(resolverName, func.bind(bind));
+        continue;
+      }
+      wrapped[name][resolverName] = func.bind(bind);
     }
   }
 
@@ -43,11 +47,10 @@ const getImportedResolvers = function (imp) {
 
 const _cache = new WeakMap();
 
-const memoize = function (parentType, fieldName, resolve) {
-  debug(`memoized ${parentType}.${fieldName}`);
-
+const memoize = function (fieldName, resolve) {
   return function (_, args, context, info) {
     const key = JSON.stringify(args);
+    const { parentType } = info;
 
     debug(`executing ${parentType}.${fieldName}`);
 

package.json

@@ -5,7 +5,9 @@
   "main": "lib/index.js",
   "scripts": {
     "test": "tape test/test-*.js",
-    "start": "DEBUG=graphql-component:* GRAPHQL_DEBUG=1 node --trace-event-categories graphql examples/example-listing/server/index.js"
+    "start": "DEBUG=graphql-component:* GRAPHQL_DEBUG=1 node --trace-event-categories graphql examples/example-listing/server/index.js",
+    "lint": "eslint lib",
+    "cover": "nyc npm test"
   },
   "author": "Trevor Livingston <[email protected]>",
   "repository": "https://github.com/tlivings/graphql-component",
@@ -20,6 +22,8 @@
   "devDependencies": {
     "apollo-server": "^2.0.7",
     "casual": "^1.6.0",
+    "eslint": "^5.14.1",
+    "nyc": "^13.3.0",
     "tape": "^4.9.1"
   }
 }

test/test-directive.js

@@ -18,7 +18,7 @@ Test('wrapping', (t) => {
 
     const wrapped = Resolvers.wrapResolvers({ id: 1 }, resolvers);
 
-    const value = wrapped.Query.test({}, {}, {});
+    const value = wrapped.Query.test({}, {}, {}, { parentType: 'Query' });
 
     t.equal(value, 1, 'resolver was bound');
   });
@@ -41,12 +41,13 @@ Test('wrapping', (t) => {
     const wrapped = Resolvers.wrapResolvers(undefined, resolvers);
 
     const ctx = {};
+    const info = { parentType: 'Query' };
 
-    let value = wrapped.Query.test({}, {}, ctx);
+    let value = wrapped.Query.test({}, {}, ctx, info);
 
     t.equal(value, 1, 'expected value');
 
-    value = wrapped.Query.test({}, {}, ctx);
+    value = wrapped.Query.test({}, {}, ctx, info);
 
     t.equal(value, 1, 'same value, only ran resolver once');
   });
@@ -64,15 +65,16 @@ Test('memoize resolver', (t) => {
     return ran;
   };
 
-  const wrapped = Resolvers.memoize('Query', 'test', resolver);
+  const wrapped = Resolvers.memoize('test', resolver);
 
   const ctx = {};
+  const info = { parentType: 'Query' };
 
-  let value = wrapped({}, {}, ctx);
+  let value = wrapped({}, {}, ctx, info);
 
   t.equal(value, 1, 'expected value');
 
-  value = wrapped({}, {}, ctx);
+  value = wrapped({}, {}, ctx, info);
 
   t.equal(value, 1, 'same value, only ran resolver once');
 });