micro/plugin/default.go
ben-toogood 174e44b846
Deprecate client/selector (#1767)
* client/{grpc,rpc}: depricate selector (wip)

* {client,cmd}: remove client/selector

* deprecate client/selector

* router/static: fix lookup

* config/cmd: add support for legacy static selector flag

* config/cmd: add support for legacy dns selector flag
2020-07-01 17:06:59 +01:00

128 lines
3.2 KiB
Go

// Package plugin provides the ability to load plugins
package plugin
import (
"errors"
"fmt"
"os"
"os/exec"
"path/filepath"
pg "plugin"
"strings"
"text/template"
"github.com/micro/go-micro/v2/broker"
"github.com/micro/go-micro/v2/client"
"github.com/micro/go-micro/v2/config/cmd"
"github.com/micro/go-micro/v2/registry"
"github.com/micro/go-micro/v2/selector"
"github.com/micro/go-micro/v2/server"
"github.com/micro/go-micro/v2/transport"
)
type plugin struct{}
// Init sets up the plugin
func (p *plugin) Init(c *Config) error {
switch c.Type {
case "broker":
pg, ok := c.NewFunc.(func(...broker.Option) broker.Broker)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultBrokers[c.Name] = pg
case "client":
pg, ok := c.NewFunc.(func(...client.Option) client.Client)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultClients[c.Name] = pg
case "registry":
pg, ok := c.NewFunc.(func(...registry.Option) registry.Registry)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultRegistries[c.Name] = pg
case "selector":
pg, ok := c.NewFunc.(func(...selector.Option) selector.Selector)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultSelectors[c.Name] = pg
case "server":
pg, ok := c.NewFunc.(func(...server.Option) server.Server)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultServers[c.Name] = pg
case "transport":
pg, ok := c.NewFunc.(func(...transport.Option) transport.Transport)
if !ok {
return fmt.Errorf("Invalid plugin %s", c.Name)
}
cmd.DefaultTransports[c.Name] = pg
default:
return fmt.Errorf("Unknown plugin type: %s for %s", c.Type, c.Name)
}
return nil
}
// Load loads a plugin created with `go build -buildmode=plugin`
func (p *plugin) Load(path string) (*Config, error) {
plugin, err := pg.Open(path)
if err != nil {
return nil, err
}
s, err := plugin.Lookup("Plugin")
if err != nil {
return nil, err
}
pl, ok := s.(*Config)
if !ok {
return nil, errors.New("could not cast Plugin object")
}
return pl, nil
}
// Generate creates a go file at the specified path.
// You must use `go build -buildmode=plugin`to build it.
func (p *plugin) Generate(path string, c *Config) error {
f, err := os.Create(path)
if err != nil {
return err
}
defer f.Close()
t, err := template.New(c.Name).Parse(tmpl)
if err != nil {
return err
}
return t.Execute(f, c)
}
// Build generates a dso plugin using the go command `go build -buildmode=plugin`
func (p *plugin) Build(path string, c *Config) error {
path = strings.TrimSuffix(path, ".so")
// create go file in tmp path
temp := os.TempDir()
base := filepath.Base(path)
goFile := filepath.Join(temp, base+".go")
// generate .go file
if err := p.Generate(goFile, c); err != nil {
return err
}
// remove .go file
defer os.Remove(goFile)
if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil && !os.IsExist(err) {
return fmt.Errorf("Failed to create dir %s: %v", filepath.Dir(path), err)
}
cmd := exec.Command("go", "build", "-buildmode=plugin", "-o", path+".so", goFile)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
return cmd.Run()
}