README

This library allow using GraphQL subscription over Mercure protocol with any implementation of GraphQL PHP. It Comes out-of-the-box with a Symfony Bridge so it can be easily combine with OverblogGraphQLBundle or API Platform or other Symfony implementation based on GraphQL PHP.

Installation

composer req overblog/graphql-subscription

Default builder executor

<?php
use GraphQL\Executor\ExecutionResult;
use GraphQL\GraphQL;

function (
    $schema,
    $source,
    $rootValue = null,
    $context = null,
    $variableValues = null,
    ?string $operationName = null
): ExecutionResult {
    return GraphQL::executeQuery(...func_get_args());
}

CORS preflight headers

This library does not handle natively CORS preflight headers.

Symfony

Installation without flex

Add the OverblogGraphQLSubscriptionBundle to your application's kernel:

    public function registerBundles()
    {
        $bundles = [
            // ...
            new Overblog\GraphQLSubscription\Bridge\Symfony\OverblogGraphQLSubscriptionBundle(),
            // ...
        ];
        // ...
    }

Configuration

Symfony Flex generates:

• default configuration in config/packages/graphql_subscription.yaml.

  overblog_graphql_subscription:
      topic_url_pattern: "http://localhost:8000/subscriptions/{channel}/{id}.json"
      mercure_hub:
  #       Will use the mercure bundle default publisher
          handler_id: ~
  #       Uncomment to use without mercure bundle
  #        url: "https://mercure.roks/hub"
  #        publish:
  #            secret_key: "!mySuperPublisherSecretKey!"
  #      Uncomment to expose public hubUrl on start in payload
  #      public_url: "https://mercure.roks/hub"
        subscribe:
              secret_key: "!mySuperSubscriberSecretKey!"
  #    Uncomment to modify storage filesystem default path
  #    storage:
  #        path: "%kernel.project_dir%/var/graphql-subscriber"
  #   The graphql query handler
  #   for OverblogGraphQLBundle: "Overblog\\GraphQLBundle\\Request\\Executor::execute"
  #   for API-Plateform: "api_platform.graphql.executor::executeQuery"
      graphql_executor: ~
      schema_builder: ~

• default routes in config/routes/graphql_subscription.yaml

  overblog_graphql_subscription_endpoint:
      resource: "@OverblogGraphQLSubscriptionBundle/Resources/config/routing/single.yaml"
      prefix: /subscriptions
  #   Only for Symfony >= 4.2
  #    trailing_slash_on_root: false
  
  # Uncomment to enabled multiple schema
  #overblog_graphql_subscription_multiple_endpoint:
  #  resource: "@OverblogGraphQLSubscriptionBundle/Resources/config/routing/multiple.yaml"
  #  prefix: /subscriptions

Handling CORS preflight headers

NelmioCorsBundle is recommended to manage CORS preflight, follow instructions to install it.

Here a configuration assuming that subscription endpoint is /subscriptions:

nelmio_cors:
    defaults:
        origin_regex: true
        allow_origin: ['%env(CORS_ALLOW_ORIGIN)%']
        allow_methods: ['GET', 'OPTIONS', 'POST']
        allow_headers: ['Content-Type']
        max_age: 3600
    paths:
        '^/subscriptions': ~