ipld-eth-server/pkg/graphql/service.go
2022-09-14 01:20:16 -04:00

112 lines
3.5 KiB
Go

// VulcanizeDB
// Copyright © 2020 Vulcanize
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package graphql
import (
"fmt"
"net"
"net/http"
"github.com/ethereum/go-ethereum/cmd/utils"
"github.com/ethereum/go-ethereum/node"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/rpc"
"github.com/graph-gophers/graphql-go"
"github.com/graph-gophers/graphql-go/relay"
"github.com/sirupsen/logrus"
"github.com/cerc-io/ipld-eth-server/v4/pkg/eth"
)
// Service encapsulates a GraphQL service.
type Service struct {
endpoint string // The host:port endpoint for this service.
cors []string // Allowed CORS domains
vhosts []string // Recognised vhosts
timeouts rpc.HTTPTimeouts // Timeout settings for HTTP requests.
backend *eth.Backend // The backend that queries will operate onn.
handler http.Handler // The `http.Handler` used to answer queries.
listener net.Listener // The listening socket.
}
// New constructs a new GraphQL service instance.
func New(backend *eth.Backend, endpoint string, cors, vhosts []string, timeouts rpc.HTTPTimeouts) (*Service, error) {
return &Service{
endpoint: endpoint,
cors: cors,
vhosts: vhosts,
timeouts: timeouts,
backend: backend,
}, nil
}
// Protocols returns the list of protocols exported by this service.
func (s *Service) Protocols() []p2p.Protocol { return nil }
// APIs returns the list of APIs exported by this service.
func (s *Service) APIs() []rpc.API { return nil }
// Start is called after all services have been constructed and the networking
// layer was also initialized to spawn any goroutines required by the service.
func (s *Service) Start(server *p2p.Server) error {
var err error
s.handler, err = NewHandler(s.backend)
if err != nil {
return err
}
handler := node.NewHTTPHandlerStack(s.handler, s.cors, s.vhosts, nil)
// start http server
_, addr, err := node.StartHTTPEndpoint(s.endpoint, rpc.DefaultHTTPTimeouts, handler)
if err != nil {
utils.Fatalf("Could not start RPC api: %v", err)
}
extapiURL := fmt.Sprintf("http://%v/", addr)
logrus.Infof("graphQL endpoint opened for url %s", extapiURL)
return nil
}
// newHandler returns a new `http.Handler` that will answer GraphQL queries.
// It additionally exports an interactive query browser on the / endpoint.
func NewHandler(backend *eth.Backend) (http.Handler, error) {
q := Resolver{backend}
s, err := graphql.ParseSchema(schema, &q)
if err != nil {
return nil, err
}
h := &relay.Handler{Schema: s}
mux := http.NewServeMux()
mux.Handle("/", GraphiQL{})
mux.Handle("/graphql", h)
mux.Handle("/graphql/", h)
return mux, nil
}
// Stop terminates all goroutines belonging to the service, blocking until they
// are all terminated.
func (s *Service) Stop() error {
if s.listener != nil {
s.listener.Close()
s.listener = nil
logrus.Debugf("graphQL endpoint closed for url %s", fmt.Sprintf("http://%s", s.endpoint))
}
return nil
}