feat(spi): 新增spi包及其实现 (#258)

.github/workflows/go.yml

@@ -30,6 +30,7 @@ jobs:
         with:
           go-version: 1.20.0
 
+
       - name: Build
         run: go build -v ./...
 

.golangci.yml

@@ -14,5 +14,9 @@
 
 run:
   go: '1.20'
-  skip-dirs:
-    - .idea
+issues:
+  exclude-dirs:
+    - .idea
+linters-settings:
+  errcheck:
+    ignore: ''

go.mod

@@ -5,6 +5,7 @@ go 1.20
 require (
 	github.com/DATA-DOG/go-sqlmock v1.5.0
 	github.com/mattn/go-sqlite3 v1.14.15
+	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.8.4
 	golang.org/x/exp v0.0.0-20231006140011-7918f672742d
 	golang.org/x/sync v0.4.0

go.sum

@@ -13,6 +13,8 @@ github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/mattn/go-sqlite3 v1.14.15 h1:vfoHhTN1af61xCRSWzFIWzx2YskyMTwHLrExkBOjvxI=
 github.com/mattn/go-sqlite3 v1.14.15/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=

spi/spi.go

@@ -0,0 +1,76 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package spi
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"plugin"
+
+	"github.com/pkg/errors"
+)
+
+// LoadService 加载 dir 下面的所有的实现了 T 接口的类型
+// 举个例子来说，如果你有一个叫做 UserService 的接口
+// 而后你将所有的实现都放到了 /ext/user_service 目录下
+// 并且所有的实现，虽然在不同的包，但是都叫做 UserService
+// 那么我可以执行 LoadService("/ext/user_service", "UserService")
+// 加载到所有的实现
+// LoadService 加载 dir 下面的所有的实现了 T 接口的类型
+
+var (
+	ErrDirNotFound        = errors.New("ekit: 目录不存在")
+	ErrSymbolNameIsEmpty  = errors.New("ekit: 结构体名不能为空")
+	ErrOpenPluginFailed   = errors.New("ekit: 打开插件失败")
+	ErrSymbolNameNotFound = errors.New("ekit: 从插件中查找对象失败")
+	ErrInvalidSo          = errors.New("ekit: 插件非该接口类型")
+)
+
+func LoadService[T any](dir string, symName string) ([]T, error) {
+	var services []T
+	// 检查目录是否存在
+	if _, err := os.Stat(dir); os.IsNotExist(err) {
+		return nil, fmt.Errorf("%w", ErrDirNotFound)
+	}
+	if symName == "" {
+		return nil, fmt.Errorf("%w", ErrSymbolNameIsEmpty)
+	}
+	// 遍历目录下的所有 .so 文件
+	err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
+		if !info.IsDir() && filepath.Ext(path) == ".so" {
+			// 打开插件
+			p, err := plugin.Open(path)
+			if err != nil {
+				return fmt.Errorf("%w: %w", ErrOpenPluginFailed, err)
+			}
+			// 查找变量
+			sym, err := p.Lookup(symName)
+			if err != nil {
+				return fmt.Errorf("%w: %w", ErrSymbolNameNotFound, err)
+			}
+
+			// 尝试将符号断言为接口类型
+			service, ok := sym.(T)
+			if !ok {
+				return fmt.Errorf("%w", ErrInvalidSo)
+			}
+			// 收集服务
+			services = append(services, service)
+		}
+		return nil
+	})
+	return services, err
+}

spi/spi_test.go

@@ -0,0 +1,132 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package spi
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/stretchr/testify/suite"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type LoadServiceSuite struct {
+	suite.Suite
+}
+
+func (l *LoadServiceSuite) SetupTest() {
+	t := l.T()
+	wd, err := os.Getwd()
+	require.NoError(t, err)
+	cmd := exec.Command("go", "generate", "./...")
+	cmd.Dir = filepath.Join(wd, "testdata")
+	output, err := cmd.CombinedOutput()
+	require.NoError(t, err, fmt.Sprintf("执行 go generate 失败: %v\n%s", err, output))
+}
+
+func (l *LoadServiceSuite) Test_LoadService() {
+	t := l.T()
+	testcases := []struct {
+		name       string
+		dir        string
+		svcName    string
+		want       []string
+		assertFunc assert.ErrorAssertionFunc
+	}{
+		{
+			name:       "有一个插件",
+			dir:        "./testdata/user_service",
+			svcName:    "UserSvc",
+			want:       []string{"Get"},
+			assertFunc: assert.NoError,
+		},
+		{
+			name:       "有两个插件",
+			dir:        "./testdata/user_service2",
+			svcName:    "UserSvc",
+			want:       []string{"A", "B"},
+			assertFunc: assert.NoError,
+		},
+		{
+			name: "目录不存在",
+			dir:  "./notfound",
+			assertFunc: func(t assert.TestingT, err error, i ...interface{}) bool {
+				return assert.ErrorIs(t, err, ErrDirNotFound)
+			},
+		},
+		{
+			name:    "svcName为空",
+			dir:     "./testdata/user_service2",
+			svcName: "",
+			assertFunc: func(t assert.TestingT, err error, i ...interface{}) bool {
+				return assert.ErrorIs(t, err, ErrSymbolNameIsEmpty)
+			},
+		},
+		{
+			name:    "svcName没找到",
+			dir:     "./testdata/user_service2",
+			svcName: "notfound",
+			assertFunc: func(t assert.TestingT, err error, i ...interface{}) bool {
+				return assert.ErrorIs(t, err, ErrSymbolNameNotFound)
+			},
+		},
+		{
+			name:    "加载的对象未实现对应的抽象",
+			dir:     "./testdata/user_service3",
+			svcName: "UserSvc",
+			assertFunc: func(t assert.TestingT, err error, i ...interface{}) bool {
+				return assert.ErrorIs(t, err, ErrInvalidSo)
+			},
+		},
+	}
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			list, err := LoadService[UserService](tc.dir, tc.svcName)
+			tc.assertFunc(t, err)
+			if err != nil {
+				return
+			}
+			ans := make([]string, 0, len(list))
+			for _, svc := range list {
+				ans = append(ans, svc.Get())
+			}
+			assert.Equal(t, tc.want, ans)
+		})
+	}
+}
+
+func TestLoadServiceSuite(t *testing.T) {
+	suite.Run(t, new(LoadServiceSuite))
+}
+
+type UserService interface {
+	Get() string
+}
+
+func ExampleLoadService() {
+	getters, err := LoadService[UserService]("./testdata/user_service", "UserSvc")
+	fmt.Println(err)
+	for _, getter := range getters {
+		fmt.Println(getter.Get())
+	}
+	// Output:
+	// <nil>
+	// Get
+}

spi/testdata/user_service/a.go

@@ -0,0 +1,25 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package main
+
+// 测试用
+//go:generate go build -race --buildmode=plugin   -o a.so ./a.go
+
+type UserService struct{}
+
+func (u UserService) Get() string {
+	return "Get"
+}
+
+var UserSvc UserService

spi/testdata/user_service2/a/a.go

@@ -0,0 +1,29 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:generate go build  -race --buildmode=plugin  -o ../a.so ./a.go
+
+package main
+
+// 测试用
+
+type UserService struct{}
+
+// GetName returns the name of the service
+func (u UserService) Get() string {
+	return "A"
+}
+
+// 导出对象
+var UserSvc UserService

spi/testdata/user_service2/b/b.go

@@ -0,0 +1,28 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:generate go build -race --buildmode=plugin   -o ../b.so ./b.go
+package main
+
+// 测试用
+
+type UserService struct{}
+
+// GetName returns the name of the service
+func (u UserService) Get() string {
+	return "B"
+}
+
+// 导出对象
+var UserSvc UserService

spi/testdata/user_service3/a.go

@@ -0,0 +1,27 @@
+// Copyright 2021 ecodeclub
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+// 测试用
+
+//go:generate go build -race --buildmode=plugin   -o a.so ./a.go
+
+type UserService struct{}
+
+func (u UserService) GetV1() string {
+	return "Get"
+}
+
+var UserSvc UserService