Merge pull request #59 from Medium/nicks/lazy

Evaluate template objects lazily. Reduces medium protogen from 70s -> 2.5s

lib/descriptors/ExtendDescriptor.js

@@ -48,9 +48,14 @@ ExtendDescriptor.prototype.inspect = function () {
 
 /** @override */
 ExtendDescriptor.prototype.toTemplateObject = function () {
+  var fields = null
+  var self = this
   return {
     name: this._name,
-    fields: helper.values(this._fields, helper.toTemplateObject)
+    get fields() {
+      if (fields) return fields
+      return ((fields = helper.values(self._fields, helper.toTemplateObject)))
+    }
   }
 }
 

lib/descriptors/FieldDescriptor.js

@@ -33,6 +33,9 @@ module.exports = FieldDescriptor
 
 /** @override */
 FieldDescriptor.prototype.toTemplateObject = function () {
+  var typeDescriptor = null
+  var self = this
+
   return {
     name: this._name,
     camelName: this.getCamelName(),
@@ -41,9 +44,11 @@ FieldDescriptor.prototype.toTemplateObject = function () {
     rawType: this._type,
     baseType: this.getBaseType(),
     type: this.getType(),
-    typeDescriptor: this._typeDescriptor ?
-        this._typeDescriptor.toTemplateObject(true /* skipFields to avoid infinite loops */) :
-        null,
+    get typeDescriptor() {
+      if (typeDescriptor) return typeDescriptor
+      if (!self._typeDescriptor) return null
+      return ((typeDescriptor = self._typeDescriptor.toTemplateObject()))
+    },
     tag: this._tag,
     isOptional: this._isOptional,
     isRepeated: this._isRepeated,

lib/descriptors/MessageDescriptor.js

@@ -37,24 +37,35 @@ MessageDescriptor.prototype.inspect = function () {
   return util.inspect(this.toTemplateObject(), false, null)
 }
 
+/** @override */
+MessageDescriptor.prototype.toTemplateObject = function () {
+  var fields = null
+  var oneofs = null
+  var messages = null
+  var enums = null
+  var self = this
 
-/**
- * @param {boolean=} opt_skipFields
- * @override
- */
-MessageDescriptor.prototype.toTemplateObject = function (opt_skipFields) {
   var obj = {
     name: this._name,
     fullName: helper.joinPackage(this._package, this._name),
     camelName: this.getCamelName(),
-    options: this._options
-  }
-
-  if (!opt_skipFields) {
-    obj.fields = helper.values(this._fields, helper.toTemplateObject),
-    obj.oneofs = this._oneofs.map(helper.toTemplateObject),
-    obj.messages = helper.values(this._messages, helper.toTemplateObject),
-    obj.enums = helper.values(this._enums, helper.toTemplateObject)
+    options: this._options,
+    get fields() {
+      if (fields) return fields
+      return ((fields = helper.values(self._fields, helper.toTemplateObject)))
+    },
+    get oneofs() {
+      if (oneofs) return oneofs
+      return ((oneofs = helper.values(self._oneofs, helper.toTemplateObject)))
+    },
+    get messages() {
+      if (messages) return messages
+      return ((messages = helper.values(self._messages, helper.toTemplateObject)))
+    },
+    get enums() {
+      if (enums) return enums
+      return ((enums = helper.values(self._enums, helper.toTemplateObject)))
+    }
   }
 
   return obj

lib/descriptors/MethodDescriptor.js

@@ -32,6 +32,10 @@ module.exports = MethodDescriptor
 
 /** @override */
 MethodDescriptor.prototype.toTemplateObject = function () {
+  var inputTypeDescriptor = null
+  var outputTypeDescriptor = null
+  var self = this
+
   return {
     name: this._name,
     camelName: this.getCamelName(),
@@ -47,10 +51,17 @@ MethodDescriptor.prototype.toTemplateObject = function () {
     rawInputType: this._inputType,
     rawOutputType: this._outputType,
 
-    inputTypeDescriptor: this._inputTypeDescriptor ?
-      this._inputTypeDescriptor.toTemplateObject() : null,
-    outputTypeDescriptor: this._outputTypeDescriptor ?
-      this._outputTypeDescriptor.toTemplateObject() : null,
+    get inputTypeDescriptor() {
+      if (inputTypeDescriptor) return inputTypeDescriptor
+      if (!self._inputTypeDescriptor) return null
+      return ((inputTypeDescriptor = self._inputTypeDescriptor.toTemplateObject()))
+    },
+
+    get outputTypeDescriptor() {
+      if (outputTypeDescriptor) return outputTypeDescriptor
+      if (!self._outputTypeDescriptor) return null
+      return ((outputTypeDescriptor = self._outputTypeDescriptor.toTemplateObject()))
+    },
 
     options: this._options
   }
@@ -162,4 +173,3 @@ MethodDescriptor.prototype.addOption = function (name, value) {
 MethodDescriptor.prototype.getOption = function (name) {
   return this._options[name]
 }
-

lib/descriptors/ProtoDescriptor.js

@@ -25,8 +25,6 @@ function ProtoDescriptor(filePath) {
   this._services = {}
   this._enums = {}
   this._extends = {}
-
-  this._recursing = false
 }
 util.inherits(ProtoDescriptor, Descriptor)
 module.exports = ProtoDescriptor
@@ -50,23 +48,39 @@ ProtoDescriptor.prototype.inspect = function () {
 
 /** @override */
 ProtoDescriptor.prototype.toTemplateObject = function () {
-  if (this._recursing) {
-    throw new Error('import loop detected: ' + this.getName())
-  }
-  this._recursing = true
+  var messages = null
+  var services = null
+  var extendObjs = null
+  var enums = null
+  var imports = null
+  var self = this
 
   var result = {
     name: this.getName(),
     package: this._package,
     options: this._options,
-    messages: helper.values(this._messages, helper.toTemplateObject),
-    services: helper.values(this._services, helper.toTemplateObject),
-    extends: helper.values(this._messages, helper.toTemplateObject),
-    enums: helper.values(this._enums, helper.toTemplateObject),
     importNames: this._importNames,
-    imports: this._imports.map(helper.toTemplateObject)
+    get messages() {
+      if (messages) return messages
+      return ((messages = helper.values(self._messages, helper.toTemplateObject)))
+    },
+    get services() {
+      if (services) return services
+      return ((services = helper.values(self._services, helper.toTemplateObject)))
+    },
+    get extends() {
+      if (extendObjs) return extendObjs
+      return ((extendObjs = helper.values(self._extends, helper.toTemplateObject)))
+    },
+    get enums() {
+      if (enums) return enums
+      return ((enums = helper.values(self._enums, helper.toTemplateObject)))
+    },
+    get imports() {
+      if (imports) return imports
+      return ((imports = self._imports.map(helper.toTemplateObject)))
+    }
   }
-  this._recursing = false
   return result
 }
 

lib/descriptors/ServiceDescriptor.js

@@ -31,10 +31,15 @@ ServiceDescriptor.prototype.inspect = function () {
 
 /** @override */
 ServiceDescriptor.prototype.toTemplateObject = function () {
+  var methods = null
+  var self = this
   return {
     name: this._name,
     fullName: helper.joinPackage(this._package, this._name),
-    methods: this._methodSequence.map(helper.toTemplateObject)
+    get methods() {
+      if (methods) return methods
+      return ((methods = self._methodSequence.map(helper.toTemplateObject)))
+    }
   }
 }
 

tests/project_test.js

@@ -194,7 +194,7 @@ builder.add(function testTypeResolutionLoop(test) {
   var dee = project.getProtos('protos/loop.proto')[0].getMessage('TweedleDee')
   var dum = dee.getField('dum')
   test.equal('TweedleDum', dum.toTemplateObject().typeDescriptor.name)
-  test.equal(null, dum.toTemplateObject().typeDescriptor.fields)
+  test.equal(1, dum.toTemplateObject().typeDescriptor.fields.length)
   test.done()
 })