initial subscription support

src/core/server/graph/common/middleware/index.ts

@@ -0,0 +1,52 @@
+import {
+    graphqlExpress,
+    ExpressGraphQLOptionsFunction,
+    GraphQLOptions,
+} from 'apollo-server-express';
+import { GraphQLError, FieldDefinitionNode, ValidationContext } from 'graphql';
+import { resolveGraphqlOptions } from 'apollo-server-core';
+import { Config } from 'talk-server/config';
+
+// Sourced from: https://github.com/apollographql/apollo-server/blob/958846887598491fadea57b3f9373d129300f250/packages/apollo-server-core/src/ApolloServer.ts#L46-L57
+const NoIntrospection = (context: ValidationContext) => ({
+    Field(node: FieldDefinitionNode) {
+        if (node.name.value === '__schema' || node.name.value === '__type') {
+            context.reportError(
+                new GraphQLError(
+                    'GraphQL introspection is not allowed in production, but the query contained __schema or __type.',
+                    [node]
+                )
+            );
+        }
+    },
+});
+
+export const graphqlMiddleware = (
+    config: Config,
+    baseOptions: GraphQLOptions | ExpressGraphQLOptionsFunction
+) => {
+    // Generate the validation rules.
+    const validationRules: Array<(context: ValidationContext) => any> = [];
+
+    if (config.get('env') !== 'production') {
+        // Disable introspection in production.
+        validationRules.push(NoIntrospection);
+    }
+
+    // Generate the actual middleware.
+    return graphqlExpress(async (req, res) => {
+        // Resolve the base options.
+        const requestOptions = await resolveGraphqlOptions(
+            baseOptions,
+            req,
+            res
+        );
+
+        // Apply the validators, sourced from: https://github.com/apollographql/apollo-server/blob/958846887598491fadea57b3f9373d129300f250/packages/apollo-server-core/src/ApolloServer.ts#L104-L107
+        requestOptions.validationRules = requestOptions.validationRules
+            ? requestOptions.validationRules.concat(validationRules)
+            : validationRules;
+
+        return requestOptions;
+    });
+};

src/core/server/graph/common/schema/index.ts

@@ -0,0 +1,15 @@
+import { addResolveFunctionsToSchema, IResolvers } from 'graphql-tools';
+import { getGraphQLProjectConfig } from 'graphql-config';
+
+export default function loadSchema(projectName: string, resolvers: IResolvers) {
+    // Load the configuration from the provided `.graphqlconfig` file.
+    const config = getGraphQLProjectConfig(__dirname, projectName);
+
+    // Get the GraphQLSchema from the configuration.
+    const schema = config.getSchema();
+
+    // Attach the resolvers to the schema.
+    addResolveFunctionsToSchema({ schema, resolvers });
+
+    return schema;
+}

src/core/server/graph/common/subscriptions/middleware.ts

@@ -0,0 +1,29 @@
+import http from 'http';
+import { SubscriptionServer } from 'subscriptions-transport-ws';
+import { GraphQLSchema, execute, subscribe } from 'graphql';
+
+export interface SubscriptionMiddlewareOptions {
+    schema: GraphQLSchema;
+    path: string;
+}
+
+export function handleSubscriptions(
+    server: http.Server,
+    { schema, path }: SubscriptionMiddlewareOptions
+): SubscriptionServer {
+    // Configure some options for the subscription system.
+    const options = {
+        schema,
+        execute,
+        subscribe,
+    };
+
+    // Configure the socket options for the websocket server. It needs to handle
+    // upgrade requests on that route.
+    const socketOption = {
+        server,
+        path,
+    };
+
+    return new SubscriptionServer(options, socketOption);
+}

src/core/server/graph/common/subscriptions/pubsub.ts

@@ -0,0 +1,15 @@
+import { RedisPubSub } from 'graphql-redis-subscriptions';
+import { createRedisClient } from 'talk-server/services/redis';
+import { Config } from 'talk-server/config';
+
+export async function createPubSub(config: Config): Promise<RedisPubSub> {
+    // Create the Redis clients for the PubSub server.
+    const publisher = await createRedisClient(config);
+    const subscriber = await createRedisClient(config);
+
+    // Create the new PubSub manager.
+    return new RedisPubSub({
+        publisher,
+        subscriber,
+    });
+}

src/core/server/graph/management/middleware.ts

@@ -1,12 +1,13 @@
-import { graphqlExpress } from 'apollo-server-express';
-import schema from './schema';
-import Context from './context';
 import { Db } from 'mongodb';
+import { GraphQLSchema } from 'graphql';
 
-export default (db: Db) =>
-    graphqlExpress(async req => {
-        return {
-            schema,
-            context: new Context({ db }),
-        };
-    });
+import { graphqlMiddleware } from 'talk-server/graph/common/middleware';
+import { Config } from 'talk-server/config';
+
+import Context from './context';
+
+export default (schema: GraphQLSchema, config: Config, db: Db) =>
+    graphqlMiddleware(config, async () => ({
+        schema,
+        context: new Context({ db }),
+    }));

src/core/server/graph/management/schema/index.ts

@@ -1,15 +1,6 @@
-import { addResolveFunctionsToSchema } from 'graphql-tools';
-import { getGraphQLProjectConfig } from 'graphql-config';
+import loadSchema from 'talk-server/graph/common/schema';
+import resolvers from 'talk-server/graph/management/resolvers';
 
-import resolvers from '../resolvers';
-
-// Load the configuration from the provided `.graphqlconfig` file.
-const config = getGraphQLProjectConfig(__dirname, 'management');
-
-// Get the GraphQLSchema from the configuration.
-const schema = config.getSchema();
-
-// Attach the resolvers to the schema.
-addResolveFunctionsToSchema({ schema, resolvers });
-
-export default schema;
+export default function getManagementSchema() {
+    return loadSchema('management', resolvers);
+}

src/core/server/graph/schemas.ts

@@ -0,0 +1,6 @@
+import { GraphQLSchema } from 'graphql';
+
+export interface Schemas {
+    management: GraphQLSchema;
+    tenant: GraphQLSchema;
+}

src/core/server/graph/tenant/middleware.ts

@@ -1,13 +1,24 @@
-import { graphqlExpress } from 'apollo-server-express';
-import schema from './schema';
-import TenantContext from './context';
 import { Db } from 'mongodb';
-import { Tenant } from 'talk-server/models/tenant';
+import { GraphQLSchema } from 'graphql';
+
+import { retrieveByDomain } from 'talk-server/models/tenant';
+import { createPubSub } from 'talk-server/graph/common/subscriptions/pubsub';
+import { Config } from 'talk-server/config';
+import { graphqlMiddleware } from 'talk-server/graph/common/middleware';
+
+import TenantContext from './context';
+
+export default async (schema: GraphQLSchema, config: Config, db: Db) => {
+    // Configure the PubSub broker.
+    const pubsub = await createPubSub(config);
+
+    return graphqlMiddleware(config, async req => {
+        // TODO: replace with shared synced cache instead of direct db access.
+        const tenant = await retrieveByDomain(db, req.hostname);
 
-export default (db: Db) =>
-    graphqlExpress(async req => {
         return {
             schema,
-            context: new TenantContext({ db, tenant: { id: '1' } as Tenant }),
+            context: new TenantContext({ db, tenant }),
         };
     });
+};

src/core/server/graph/tenant/resolvers/query.ts

@@ -1,12 +1,13 @@
-import Context from 'talk-server/graph/tenant/context';
+import TenantContext from 'talk-server/graph/tenant/context';
 import { Asset } from 'talk-server/models/asset';
 
 export default {
     asset: async (
         _: any,
         { id, url }: { id?: string; url: string },
-        ctx: Context
+        ctx: TenantContext
     ): Promise<Asset> => {
         return ctx.loaders.Assets.asset.load(id);
     },
+    settings: async (parent: any, args: any, ctx: TenantContext) => ctx.tenant,
 };

src/core/server/graph/tenant/schema/index.ts

@@ -1,15 +1,6 @@
-import { addResolveFunctionsToSchema } from 'graphql-tools';
-import { getGraphQLProjectConfig } from 'graphql-config';
+import loadSchema from 'talk-server/graph/common/schema';
+import resolvers from 'talk-server/graph/tenant/resolvers';
 
-import resolvers from '../resolvers';
-
-// Load the configuration from the provided `.graphqlconfig` file.
-const config = getGraphQLProjectConfig(__dirname, 'tenant');
-
-// Get the GraphQLSchema from the configuration.
-const schema = config.getSchema();
-
-// Attach the resolvers to the schema.
-addResolveFunctionsToSchema({ schema, resolvers });
-
-export default schema;
+export default function getTenantSchema() {
+    return loadSchema('tenant', resolvers);
+}