package plugin
import (
"crypto/tls"
"fmt"
"net"
"time"
"github.com/hashicorp/go-plugin/internal/plugin"
"golang.org/x/net/context"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/health/grpc_health_v1"
)
func dialGRPCConn(tls *tls.Config, dialer func(string, time.Duration) (net.Conn, error)) (*grpc.ClientConn, error) {
// Build dialing options.
opts := make([]grpc.DialOption, 0, 5)
// We use a custom dialer so that we can connect over unix domain sockets.
opts = append(opts, grpc.WithDialer(dialer))
// Fail right away
opts = append(opts, grpc.FailOnNonTempDialError(true))
// If we have no TLS configuration set, we need to explicitly tell grpc
// that we're connecting with an insecure connection.
if tls == nil {
opts = append(opts, grpc.WithInsecure())
} else {
opts = append(opts, grpc.WithTransportCredentials(
credentials.NewTLS(tls)))
}
// Connect. Note the first parameter is unused because we use a custom
// dialer that has the state to see the address.
conn, err := grpc.Dial("unused", opts...)
if err != nil {
return nil, err
}
return conn, nil
}
// newGRPCClient creates a new GRPCClient. The Client argument is expected
// to be successfully started already with a lock held.
func newGRPCClient(doneCtx context.Context, c *Client) (*GRPCClient, error) {
conn, err := dialGRPCConn(c.config.TLSConfig, c.dialer)
if err != nil {
return nil, err
}
// Start the broker.
brokerGRPCClient := newGRPCBrokerClient(conn)
broker := newGRPCBroker(brokerGRPCClient, c.config.TLSConfig)
go broker.Run()
go brokerGRPCClient.StartStream()
cl := &GRPCClient{
Conn: conn,
Plugins: c.config.Plugins,
doneCtx: doneCtx,
broker: broker,
controller: plugin.NewGRPCControllerClient(conn),
}
return cl, nil
}
// GRPCClient connects to a GRPCServer over gRPC to dispense plugin types.
type GRPCClient struct {
Conn *grpc.ClientConn
Plugins map[string]Plugin
doneCtx context.Context
broker *GRPCBroker
controller plugin.GRPCControllerClient
}
// ClientProtocol impl.
func (c *GRPCClient) Close() error {
c.broker.Close()
c.controller.Shutdown(c.doneCtx, &plugin.Empty{})
return c.Conn.Close()
}
// ClientProtocol impl.
func (c *GRPCClient) Dispense(name string) (interface{}, error) {
raw, ok := c.Plugins[name]
if !ok {
return nil, fmt.Errorf("unknown plugin type: %s", name)
}
p, ok := raw.(GRPCPlugin)
if !ok {
return nil, fmt.Errorf("plugin %q doesn't support gRPC", name)
}
return p.GRPCClient(c.doneCtx, c.broker, c.Conn)
}
// ClientProtocol impl.
func (c *GRPCClient) Ping() error {
client := grpc_health_v1.NewHealthClient(c.Conn)
_, err := client.Check(context.Background(), &grpc_health_v1.HealthCheckRequest{
Service: GRPCServiceName,
})
return err
}