refactor: plugin functions can be defined in any format

plugin/host/host.go

@@ -0,0 +1,50 @@
+package host
+
+import (
+	"os"
+	"os/exec"
+
+	hclog "github.com/hashicorp/go-hclog"
+	"github.com/hashicorp/go-plugin"
+
+	"github.com/httprunner/hrp/plugin/shared"
+)
+
+var client *plugin.Client
+
+func Init(path string) (shared.FuncCaller, error) {
+	// launch the plugin process
+	client = plugin.NewClient(&plugin.ClientConfig{
+		HandshakeConfig: shared.HandshakeConfig,
+		Plugins: map[string]plugin.Plugin{
+			shared.Name: &shared.HashicorpPlugin{},
+		},
+		Cmd: exec.Command(path),
+		Logger: hclog.New(&hclog.LoggerOptions{
+			Name:   shared.Name,
+			Output: os.Stdout,
+			Level:  hclog.Info,
+		}),
+	})
+
+	// Connect via RPC
+	rpcClient, err := client.Client()
+	if err != nil {
+		return nil, err
+	}
+
+	// Request the plugin
+	raw, err := rpcClient.Dispense(shared.Name)
+	if err != nil {
+		return nil, err
+	}
+
+	// We should have a Function now! This feels like a normal interface
+	// implementation but is in fact over an RPC connection.
+	function := raw.(shared.FuncCaller)
+	return function, nil
+}
+
+func Quit() {
+	client.Kill()
+}