Further documentation improvements

UPGRADE.md

@@ -1,6 +1,6 @@
 ## Upgrade v0.8.x, v0.9.x > v0.10.x
 
-### Breaking: minimum PHP version was changed from 5.4 to 5.5
+### Breaking: changed minimum PHP version from 5.4 to 5.5
 It allows us to leverage `::class` constant, `generators` and other features of newer PHP versions.
 
 ### Breaking: default error formatting
@@ -71,8 +71,9 @@ to adjust if you were checking for this error in your custom error formatters.
 ### Breaking: removed previously deprecated ability to define type as callable
 See https://github.com/webonyx/graphql-php/issues/35
 
-### Deprecated: `GraphQL\GraphQL::executeAndReturnResult` renamed to `GraphQL\GraphQL::executeQuery`
+### Deprecated: `GraphQL\GraphQL::executeAndReturnResult` 
-Old method name is still available, but will trigger deprecation warning in next version.
+Method is renamed to `GraphQL\GraphQL::executeQuery`. Old method name is still available, 
+but will trigger deprecation warning in the next version.
 
 ### Deprecated: `GraphQL\GraphQL::execute`
 Use `GraphQL\GraphQL::executeQuery()->toArray()` instead.
@@ -95,6 +96,13 @@ $schema->assertValid();
 ``` 
 See https://github.com/webonyx/graphql-php/issues/148
 
+### Non-breaking: usage on async platforms
+When using the library on async platforms use separate method `GraphQL::promiseToExecute()`. 
+It requires promise adapter in it's first argument and always returns a `Promise`.
+
+Old methods `GraphQL::execute` and `GraphQL::executeAndReturnResult` still work in backwards-compatible manner, 
+but they are deprecated and will be removed eventually.
+
 ## Upgrade v0.7.x > v0.8.x
 All of those changes apply to those who extends various parts of this library.
 If you only use the library and don't try to extend it - everything should work without breaks.

docs/data-fetching.md

@@ -3,10 +3,10 @@ GraphQL is data-storage agnostic. You can use any underlying data storage engine
 plain files or in-memory data structures.
 
 In order to convert GraphQL query to PHP array **graphql-php** traverses query fields (using depth-first algorithm) and 
-runs special `resolve` function on each field. This `resolve` function is provided by you as a part of 
+runs special **resolve** function on each field. This **resolve** function is provided by you as a part of 
 [field definition](type-system/object-types/#field-configuration-options) or [query execution call](executing-queries/#overview).
 
-Result returned by `resolve` function is directly included in response (for scalars and enums)
+Result returned by **resolve** function is directly included in response (for scalars and enums)
 or passed down to nested fields (for objects).
 
 Let's walk through an example. Consider following GraphQL query:
@@ -22,7 +22,7 @@ Let's walk through an example. Consider following GraphQL query:
 }
 ```
 
-We need Schema that can fulfill it. On the very top level Schema contains Query type:
+We need a Schema that can fulfill it. On the very top level the Schema contains Query type:
 
 ```php
 $queryType = new ObjectType([
@@ -44,12 +44,12 @@ $queryType = new ObjectType([
 ]);
 ```
 
-As we see field `lastStory` has `resolve` function that is responsible for fetching data.
+As we see field **lastStory** has **resolve** function that is responsible for fetching data.
 
 In our example we simply return array value, but in real-world application you would query
 your database/cache/search index and return result.
 
-Since `lastStory` is of complex type `BlogStory` this result is passed down to fields of this type:
+Since **lastStory** is of composite type **BlogStory** this result is passed down to fields of this type:
 
 ```php
 $blogStoryType = new ObjectType([
@@ -81,15 +81,15 @@ $blogStoryType = new ObjectType([
 ]);
 ```
 
-Here `$blogStory` is the array returned by `lastStory` field above. 
+Here **$blogStory** is the array returned by **lastStory** field above. 
 
-Again: in real-world applications you would fetch user data from datastore by `authorId` and return it.
+Again: in real-world applications you would fetch user data from datastore by **authorId** and return it.
 Also note that you don't have to return arrays. You can return any value, **graphql-php** will pass it untouched
 to nested resolvers.
 
-But then the question appears - field `title` has no `resolve` option. How is it resolved?
+But then the question appears - field **title** has no **resolve** option. How is it resolved?
 
-The answer is: there is default resolver for all fields. When you define your own `resolve` function
+There is a default resolver for all fields. When you define your own **resolve** function
 for a field you simply override this default resolver.
 
 # Default Field Resolver
@@ -114,12 +114,10 @@ function defaultFieldResolver($source, $args, $context, ResolveInfo $info)
 }
 ```
 
-As you see it returns value by key (for arrays) or property (for objects). If value is not set - it returns `null`.
+As you see it returns value by key (for arrays) or property (for objects). 
+If value is not set - it returns **null**.
 
-To override default resolver - use:
+To override the default resolver, pass it as an argument of [executeQuery](executing-queries) call.
-```php
-GraphQL\GraphQL::setDefaultFieldResolver($myResolverCallback);
-```
 
 # Default Field Resolver per Type
 Sometimes it might be convenient to set default field resolver per type. You can do so by providing
@@ -154,8 +152,8 @@ Keep in mind that **field resolver** has precedence over **default field resolve
 # Solving N+1 Problem
 Since: 0.9.0
 
-One of the most annoying problems with data fetching is so-called [N+1 problem](https://secure.phabricator.com/book/phabcontrib/article/n_plus_one/).
+One of the most annoying problems with data fetching is a so-called 
-
+[N+1 problem](https://secure.phabricator.com/book/phabcontrib/article/n_plus_one/). <br>
 Consider following GraphQL query:
 ```
 {
@@ -219,28 +217,41 @@ In this example only one query will be executed for all story authors comparing
 in naive implementation.
 
 # Async PHP
-Since: 0.9.0
+Since: 0.10.0 (version 0.9.0 had slightly different API which is deprecated)
 
 If your project runs in environment that supports async operations 
-(like `HHVM`, `ReactPHP`, `Icicle.io`, `appserver.io` `PHP threads`, etc) you can leverage
+(like HHVM, ReactPHP, Icicle.io, appserver.io, PHP threads, etc) 
-the power of your platform to resolve fields asynchronously.
+you can leverage the power of your platform to resolve some fields asynchronously.
 
 The only requirement: your platform must support the concept of Promises compatible with
 [Promises A+](https://promisesaplus.com/) specification.
 
-To enable async support - set adapter for promises:
+To start using this feature, switch facade method for query execution from 
-```
+**executeQuery** to **promiseToExecute**:
-GraphQL\GraphQL::setPromiseAdapter($adapter);
+
+```php
+$promise = GraphQL::promiseToExecute(
+    $promiseAdapter,
+    $schema, 
+    $queryString, 
+    $rootValue = null, 
+    $contextValue = null, 
+    $variableValues = null, 
+    $operationName = null,
+    $fieldResolver = null,
+    $validationRules = null
+);
+$promise->then(function(ExecutionResult $result) {
+    return $result->toArray();
+});
 ```
 
-Where `$adapter` is an instance of class implementing `GraphQL\Executor\Promise\PromiseAdapter` interface.
+Where **$promiseAdapter** is an instance of:
 
-Then in your `resolve` functions you should return `Promises` of your platform instead of 
+* For [ReactPHP](https://github.com/reactphp/react) (requires **react/promise** as composer dependency): <br> 
-`GraphQL\Deferred` instances.
+  `GraphQL\Executor\Promise\Adapter\ReactPromiseAdapter`
 
-Platforms supported out of the box:
+* Other platforms: write your own class implementing interface: <br> 
+  `GraphQL\Executor\Promise\PromiseAdapter`. 
 
-* [ReactPHP](https://github.com/reactphp/react) (requires **react/promise** as composer dependency):
+Then your **resolve** functions should return promises of your platform instead of `GraphQL\Deferred`s.
-  `GraphQL\GraphQL::setPromiseAdapter(new GraphQL\Executor\Promise\Adapter\ReactPromiseAdapter());`
-
-To integrate other platform - implement `GraphQL\Executor\Promise\PromiseAdapter` interface. 

docs/index.md

@@ -48,4 +48,7 @@ Schema Language parser.
 Ready for real-world usage. 
 
 ## Github
-Project source code is [hosted on GitHub](https://github.com/webonyx/graphql-php).
+Project source code is [hosted on GitHub](https://github.com/webonyx/graphql-php).
+
+## Framework Integrations
+Read the section about [Complementary tools](complementary-tools/).

docs/reference.md

@@ -21,8 +21,7 @@ class GraphQL
         $variableValues = null,
         $operationName = null,
         callable $fieldResolver = null,
-        array $validationRules = null,
+        array $validationRules = null
-        GraphQL\Executor\Promise\PromiseAdapter $promiseAdapter = null
     );
     
     /**
@@ -502,22 +501,20 @@ use GraphQL\Executor\Promise\PromiseAdapter;
 class Executor
 {
     /**
-     * Executes DocumentNode against given schema.
+     * Executes DocumentNode against given $schema using given $promiseAdapter for deferred resolvers.
+     * Returns promise which is always fullfilled with instance of ExecutionResult
      * 
-     * When $promiseAdapter is passed returns Promise instance produced by this adapter. 
+     * @return Promise
-     * By default simply returns ExecutionResult
-     * 
-     * @return ExecutionResult|Promise
      */
-    public static function execute(
+    public static function promiseToExecute(
+        PromiseAdapter $promiseAdapter,
         Schema $schema,
         DocumentNode $ast,
         $rootValue = null,
         $contextValue = null,
         $variableValues = null,
         $operationName = null,
-        callable $fieldResolver = null,
+        callable $fieldResolver = null
-        PromiseAdapter $promiseAdapter = null
     );
 }
 ```
@@ -601,6 +598,80 @@ class ExecutionResult implements \JsonSerializable
     }
 ```
 
+# GraphQL\Executor\Promise\PromiseAdapter
+Required for [Async PHP](data-fetching/#async-php) only.
+
+```php
+interface PromiseAdapter
+{
+    /**
+     * Return true if value is promise of underlying system
+     *
+     * @param mixed $value
+     * @return bool
+     */
+    public function isThenable($value);
+
+    /**
+     * Converts thenable of underlying system into Promise instance
+     *
+     * @param object $thenable
+     * @return Promise
+     */
+    public function convertThenable($thenable);
+
+    /**
+     * Accepts our Promise wrapper, extracts adopted promise out of it and executes actual `then` logic described
+     * in Promises/A+ specs. Then returns new wrapped Promise instance.
+     *
+     * @param Promise $promise
+     * @param callable|null $onFulfilled
+     * @param callable|null $onRejected
+     *
+     * @return Promise
+     */
+    public function then(Promise $promise, callable $onFulfilled = null, callable $onRejected = null);
+
+    /**
+     * Creates a Promise
+     *
+     * @param callable $resolver
+
+     * @return Promise
+     */
+    public function create(callable $resolver);
+
+    /**
+     * Creates a fulfilled Promise for a value if the value is not a promise.
+     *
+     * @param mixed $value
+     *
+     * @return Promise
+     */
+    public function createFulfilled($value = null);
+
+    /**
+     * Creates a rejected promise for a reason if the reason is not a promise. If
+     * the provided reason is a promise, then it is returned as-is.
+     *
+     * @param \Throwable $reason
+     *
+     * @return Promise
+     */
+    public function createRejected($reason);
+
+    /**
+     * Given an array of promises (or values), returns a promise that is fulfilled when all the
+     * items in the array are fulfilled.
+     *
+     * @param array $promisesOrValues Promises or values.
+     *
+     * @return Promise
+     */
+    public function all(array $promisesOrValues);
+}
+```
+
 # GraphQL\Type\Definition\ResolveInfo
 
 ```php
@@ -910,3 +981,9 @@ class FormattedError
     public static function prepareFormatter(callable $formatter = null, $debug);
 }
 ```
+
+# GraphQL\Server\OperationParams
+
+# GraphQL\Server\StandardServer
+
+# GraphQL\Server\Helper

docs/type-system/index.md

@@ -50,34 +50,26 @@ class MyType extends ObjectType
 }
 ```
 
-You can also mix-and-match styles for convenience. For example:
+Using [GraphQL Type language](graphql.org/learn/schema/#type-language):
-```php
-<?php
-namespace MyApp;
 
-use GraphQL\Type\Definition\ObjectType;
+```graphql
-use GraphQL\Type\Definition\Type;
+schema {
+    query: Query
+    mutation: Mutation
+}
 
-class BlogPostType extends ObjectType
+type Query {
-{
+    greetings(input: HelloInput!): String!
-    public function __construct()
+}
-    {
+
-        $config = [
+input HelloInput {
-            'fields' => [
+    firstName: String!
-                'body' => new ObjectType([
+    lastName: String
-                    'name' => 'BlogPostBody',
-                    'fields' => [
-                        'html' => Type::string(),
-                        'text' => Type::string(),
-                    ]
-                ])
-            ]
-        ];
-        parent::__construct($config);
-    }
 }
 ```
 
+[Read more](/type-system/type-language/) about it in a dedicated docs section.
+
 # Type Registry
 Every type must be presented in Schema by single instance (**graphql-php** 
 throws when it discovers several instances with the same `name` in schema).

docs/type-system/scalar-types.md

@@ -42,6 +42,7 @@ Here is an example of simple `Email` type:
 namespace MyApp;
 
 use GraphQL\Error\Error;
+use GraphQL\Error\InvariantViolation;
 use GraphQL\Language\AST\StringValueNode;
 use GraphQL\Type\Definition\ScalarType;
 use GraphQL\Utils\Utils;
@@ -62,9 +63,12 @@ class EmailType extends ScalarType
     {
         // Assuming internal representation of email is always correct:
         return $value;
-
+        
-        // If it might be incorrect and you want to make sure that only correct values are included in response -
+        // If it might be incorrect and you want to make sure that only correct values are included
-        // use following line instead:
+        // in response - use following line instead:
+        // if (!filter_var($value, FILTER_VALIDATE_EMAIL)) {
+        //     throw new InvariantViolation("Could not serialize following value as email: " . Utils::printSafe($value));
+        // }
         // return $this->parseValue($value);
     }
 
@@ -77,7 +81,7 @@ class EmailType extends ScalarType
     public function parseValue($value)
     {
         if (!filter_var($value, FILTER_VALIDATE_EMAIL)) {
-            throw new \UnexpectedValueException("Cannot represent value as email: " . Utils::printSafe($value));
+            throw new Error("Cannot represent following value as email: " . Utils::printSafeJson($value));
         }
         return $value;
     }

mkdocs.yml

@@ -15,12 +15,11 @@ pages:
   - Schema: type-system/schema.md
   - Using Type Language: type-system/type-language.md
 - Executing Queries: executing-queries.md
-- Fetching Data: data-fetching.md
+- Fetching Data (resolving fields): data-fetching.md
 - Handling Errors: error-handling.md
 # - Mutations: mutations.md
 # - Security: security.md
 # - Performance tips: performance.md
-# - Standard Server: server.md
 - How it works: how-it-works.md
 - Class Reference: reference.md
 - Complementary Tools: complementary-tools.md