[翻译]构建带 Subscriptions 的 graphql golang 后端

package main

import (
	"net/http"

	"github.com/functionalfoundry/graphqlws"
	"github.com/graphql-go/graphql"
)

func main() {
	// Create a GraphQL schema with a subscription object
	schema, err := graphql.NewSchema(graphql.SchemaConfig{
		Subscription: graphql.NewObject(...),
	})
	
	// Create a subscription manager
	subscriptionManager := graphqlws.NewSubscriptionManager(&schema)

	// Create a WebSocket/HTTP handler
	graphqlwsHandler := graphqlws.NewHandler(graphqlws.HandlerConfig{
		// Wire up the GraphqL WebSocket handler with the subscription manager
		SubscriptionManager: subscriptionManager,

		// Optional: Add a hook to resolve auth tokens into users that are
		// then stored on the GraphQL WS connections
		Authenticate: func(authToken string) (interface{}, error) {
			// This is just a dumb example
			return "Joe", nil
		},
	})

	// The handler integrates seamlessly with existing HTTP servers
	http.Handle("/subscriptions", graphqlwsHandler)
	http.ListenAndServe(":8080", nil)
}

// This assumes you have access to the above subscription manager
subscription := subscriptionManager.Subscriptions()

for _, conn := range subscriptions {
	// Things you have access to here:
	conn.ID()   // The connection ID
	conn.User() // The user returned from the subscription manager's Authenticate
	
	for _, subscription := range subscriptions[conn] {
		// Things you have access to here:
		subscription.ID            // The subscription ID (unique per conn)
		subscription.OperationName // The name of the subcription
		subscription.Query         // The subscription query/queries string
		subscription.Variables     // The subscription variables
		subscription.Document      // The GraphQL AST for the subscription
		subscription.Fields        // The names of top-level queries
		subscription.Connection    // The GraphQL WS connection

		// Prepare an execution context for running the query
		ctx := context.Context()

		// Re-execute the subscription query
		params := graphql.Params{
			Schema:         schema, // The GraphQL schema
			RequestString:  subscription.Query,
			VariableValues: subscription.Variables,
			OperationName:  subscription.OperationName,
			Context:        ctx,
		}
		result := graphql.Do(params)

		// Send query results back to the subscriber at any point
		data := graphqlws.DataMessagePayload{
			// Data can be anything (interface{})
			Data:   result.Data, 
			// Errors is optional ([]error)
			Errors: graphqlws.ErrorsFromGraphQLErrors(result.Errors),
		}
		subscription.SendData(&data)
	}
}

package main

import (
	"net/http"
	
	"github.com/functionalfoundry/graphqlws"
	"github.com/graphql-go/graphql"
	"github.com/graphql-go/handler"
)

func main() {
	// Create a GraphQL schema with a subscription object
	schema, err := graphql.NewSchema(graphql.SchemaConfig{
		Subscription: graphql.NewObject(...),
	})
	
	// Create a GraphQL over WebSocket handler
	subscriptionManager := graphqlws.NewSubscriptionManager(&schema)
	graphqlwsHandler := graphqlws.NewHandler(graphqlws.HandlerConfig{
		SubscriptionManager: subscriptionManager,
	})
	
	// Create a GraphQL over HTTP handler
	graphqlHandler := handler.New(&handler.Config{
		Schema: &schema,
		Pretty: true,
		GraphiQL: true,
	})
	
	// Serve both handlers on different endpoints
	http.Handle("/", graphqlHandler)
	http.Handle("/subscriptions", graphqlwsHandler)
	http.ListenAndServe(":8080", nil)
}