Add plugins manager

Author: razonyang

.travis.yml

@@ -14,6 +14,7 @@ jobs:
   fast_finish: true
 before_install:
   - go get github.com/mattn/goveralls
+  - go build --buildmode=plugin -o testdata/foo.so testdata/foo.go
 script:
   - go test -v -covermode=count -coverprofile=coverage.out ./...
   - go vet ./...

README.md

@@ -1,6 +1,29 @@
-# 
-[![Build Status](https://img.shields.io/travis/clevergo/____?style=for-the-badge)](https://travis-ci.org/clevergo/____)
-[![Coverage Status](https://img.shields.io/coveralls/github/clevergo/____?style=for-the-badge)](https://coveralls.io/github/clevergo/____)
-[![Go.Dev reference](https://img.shields.io/badge/go.dev-reference-blue?logo=go&logoColor=white&style=for-the-badge)](https://pkg.go.dev/clevergo.tech/____?tab=doc)
-[![Go Report Card](https://goreportcard.com/badge/github.com/clevergo/____?style=for-the-badge)](https://goreportcard.com/report/github.com/clevergo/____)
-[![Release](https://img.shields.io/github/release/clevergo/____.svg?style=for-the-badge)](https://github.com/clevergo/____/releases)
+# Go plugins manager
+[![Build Status](https://img.shields.io/travis/clevergo/plugins?style=for-the-badge)](https://travis-ci.org/clevergo/plugins)
+[![Coverage Status](https://img.shields.io/coveralls/github/clevergo/plugins?style=for-the-badge)](https://coveralls.io/github/clevergo/plugins)
+[![Go.Dev reference](https://img.shields.io/badge/go.dev-reference-blue?logo=go&logoColor=white&style=for-the-badge)](https://pkg.go.dev/clevergo.tech/plugins?tab=doc)
+[![Go Report Card](https://goreportcard.com/badge/github.com/clevergo/plugins?style=for-the-badge)](https://goreportcard.com/report/github.com/clevergo/plugins)
+[![Release](https://img.shields.io/github/release/clevergo/plugins.svg?style=for-the-badge)](https://github.com/clevergo/plugins/releases)
+
+The `plugins` is a simple Go plugins manager.
+
+## Installation
+
+```shell
+$ go get -u clevergo.tech/plugins
+```
+
+## Usage
+
+```go
+// Plugins location.
+path := "/path/to/plugins"
+// Creates a plugins manager.
+m := plugins.New(path)
+
+// Opens a Go plugins which located at {path}/foo.so
+p, err := m.Open("foo.so")
+
+// Lookup a symbol in a plugin.
+sym, err := m.Lookup("foo.so", "Bar")
+```

go.mod

@@ -1,5 +1,5 @@
-module clevergo.tech/____
+module clevergo.tech/plugins
 
 go 1.13
 
-require github.com/stretchr/testify v1.5.1 // indirect
+require github.com/stretchr/testify v1.5.1

go.sum

@@ -6,6 +6,7 @@ github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

manager.go

@@ -0,0 +1,37 @@
+// Copyright 2020 CleverGo. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package plugins
+
+import (
+	"path"
+	"plugin"
+)
+
+// Manager is a manager that manage plugins.
+type Manager struct {
+	// The location of plugins.
+	Path string
+}
+
+// New returns a plugins manager with the given path.
+func New(path string) *Manager {
+	return &Manager{
+		Path: path,
+	}
+}
+
+// Open opens a Go plugin.
+func (pm *Manager) Open(name string) (*plugin.Plugin, error) {
+	return plugin.Open(path.Join(pm.Path, name))
+}
+
+// Lookup searchs for a symbol named symName in a plugin named pluginName.
+func (pm *Manager) Lookup(pluginName, symName string) (plugin.Symbol, error) {
+	p, err := pm.Open(pluginName)
+	if err != nil {
+		return nil, err
+	}
+	return p.Lookup(symName)
+}

manager_test.go

@@ -0,0 +1,48 @@
+// Copyright 2020 CleverGo. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+package plugins
+
+import (
+	"path"
+	"plugin"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNew(t *testing.T) {
+	for _, path := range []string{"foo", "bar"} {
+		m := New(path)
+		assert.Equal(t, path, m.Path)
+	}
+}
+
+func TestManagerOpen(t *testing.T) {
+	dir := "testdata"
+	m := New(dir)
+
+	for _, name := range []string{"foo.so", "bar.so"} {
+		expectedP, expectedErr := plugin.Open(path.Join(dir, name))
+		p, err := m.Open(name)
+		assert.Equal(t, expectedErr, err)
+		assert.Equal(t, expectedP, p)
+	}
+}
+
+func TestManagerLookup(t *testing.T) {
+	dir := "testdata"
+	m := New(dir)
+
+	_, err := m.Lookup("nil", "Foo")
+	assert.NotNil(t, err)
+
+	_, err = m.Lookup("foo.so", "Bar")
+	assert.NotNil(t, err)
+
+	sym, err := m.Lookup("foo.so", "Foo")
+	assert.Nil(t, err)
+	f := sym.(func() string)
+	assert.Equal(t, "Bar", f())
+}

testdata/.gitignore

@@ -0,0 +1 @@
+*.so

testdata/foo.go

@@ -0,0 +1,9 @@
+package main
+
+// Foo returns Bar.
+func Foo() string {
+	return "Bar"
+}
+
+func mian() {
+}