go-ethereum/graphql/service.go
rene c0c01612e9
node: refactor package node (#21105)
This PR significantly changes the APIs for instantiating Ethereum nodes in
a Go program. The new APIs are not backwards-compatible, but we feel that
this is made up for by the much simpler way of registering services on
node.Node. You can find more information and rationale in the design
document: https://gist.github.com/renaynay/5bec2de19fde66f4d04c535fd24f0775.

There is also a new feature in Node's Go API: it is now possible to
register arbitrary handlers on the user-facing HTTP server. In geth, this
facility is used to enable GraphQL.

There is a single minor change relevant for geth users in this PR: The
GraphQL API is no longer available separately from the JSON-RPC HTTP
server. If you want GraphQL, you need to enable it using the
./geth --http --graphql flag combination.

The --graphql.port and --graphql.addr flags are no longer available.
2020-08-03 19:40:46 +02:00

53 lines
1.9 KiB
Go

// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package graphql
import (
"github.com/ethereum/go-ethereum/internal/ethapi"
"github.com/ethereum/go-ethereum/node"
"github.com/graph-gophers/graphql-go"
"github.com/graph-gophers/graphql-go/relay"
)
// New constructs a new GraphQL service instance.
func New(stack *node.Node, backend ethapi.Backend, cors, vhosts []string) error {
if backend == nil {
panic("missing backend")
}
// check if http server with given endpoint exists and enable graphQL on it
return newHandler(stack, backend, cors, vhosts)
}
// newHandler returns a new `http.Handler` that will answer GraphQL queries.
// It additionally exports an interactive query browser on the / endpoint.
func newHandler(stack *node.Node, backend ethapi.Backend, cors, vhosts []string) error {
q := Resolver{backend}
s, err := graphql.ParseSchema(schema, &q)
if err != nil {
return err
}
h := &relay.Handler{Schema: s}
handler := node.NewHTTPHandlerStack(h, cors, vhosts)
stack.RegisterHandler("GraphQL UI", "/graphql/ui", GraphiQL{})
stack.RegisterHandler("GraphQL", "/graphql", handler)
stack.RegisterHandler("GraphQL", "/graphql/", handler)
return nil
}