Merge pull request #106 from Peefy/feat-kcl-go-wasm-lib-example

feat: add kcl-go wasm lib example

wasm/README.md

@@ -50,6 +50,33 @@ fn main() -> Result<()> {
 }
 ```
 
+### Go
+
+```go
+package main
+
+import (
+	"fmt"
+
+	"github.com/kcl-lang/wasm-lib/pkg/module"
+)
+
+func main() {
+	m, err := module.New("../../kcl.wasm")
+	if err != nil {
+		panic(err)
+	}
+	result, err := m.Run(&module.RunOptions{
+		Filename: "test.k",
+		Source:   "a = 1",
+	})
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(result)
+}
+```
+
 ## Developing
 
 - Install `node.js`

wasm/examples/go/go.mod

@@ -0,0 +1,5 @@
+module github.com/kcl-lang/wasm-lib
+
+go 1.22.1
+
+require github.com/bytecodealliance/wasmtime-go/v22 v22.0.1

wasm/examples/go/go.sum

@@ -0,0 +1,10 @@
+github.com/bytecodealliance/wasmtime-go/v22 v22.0.1 h1:/wWcvXyffeWeDQQte3Db/fHVEov8HhxfVJ43gz9xVcM=
+github.com/bytecodealliance/wasmtime-go/v22 v22.0.1/go.mod h1:knqkvjTLavLtAXnA5NJUM0qbRiPJCVWPLXfYu75kZSo=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.0 h1:pSgiaMZlXftHpm5L7V1+rVB+AZJydKsMxsQBIJw4PKk=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

wasm/examples/go/main.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/kcl-lang/wasm-lib/pkg/module"
+)
+
+func main() {
+	m, err := module.New("../../kcl.wasm")
+	if err != nil {
+		panic(err)
+	}
+	result, err := m.Run(&module.RunOptions{
+		Filename: "test.k",
+		Source:   "a = 1",
+	})
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(result)
+}

wasm/examples/go/pkg/module/module.go

@@ -0,0 +1,108 @@
+package module
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"github.com/bytecodealliance/wasmtime-go/v22"
+)
+
+type RunOptions struct {
+	Filename string
+	Source   string
+}
+
+type KCLModule struct {
+	Instance  *wasmtime.Instance
+	Store     *wasmtime.Store
+	Memory    *wasmtime.Memory
+	KclMalloc *wasmtime.Func
+	KclFree   *wasmtime.Func
+	KclRun    *wasmtime.Func
+}
+
+func New(path string) (*KCLModule, error) {
+	dir, err := os.MkdirTemp("", "out")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+	stdoutPath := filepath.Join(dir, "stdout")
+	engine := wasmtime.NewEngine()
+	module, err := wasmtime.NewModuleFromFile(engine, path)
+	if err != nil {
+		return nil, err
+	}
+	linker := wasmtime.NewLinker(engine)
+	err = linker.DefineWasi()
+	linker.FuncWrap("env", "kclvm_plugin_invoke_json_wasm", func(_name int32, _args int32, _kwargs int32) int32 {
+		return 0
+	})
+	if err != nil {
+		return nil, err
+	}
+	wasiConfig := wasmtime.NewWasiConfig()
+	wasiConfig.SetStdoutFile(stdoutPath)
+	store := wasmtime.NewStore(engine)
+	store.SetWasi(wasiConfig)
+	instance, err := linker.Instantiate(store, module)
+	if err != nil {
+		return nil, err
+	}
+	memory := instance.Exports(store)[0].Memory()
+	malloc := instance.GetFunc(store, "kcl_malloc")
+	free := instance.GetFunc(store, "kcl_free")
+	run := instance.GetFunc(store, "kcl_run")
+	return &KCLModule{
+		Instance:  instance,
+		Store:     store,
+		Memory:    memory,
+		KclMalloc: malloc,
+		KclFree:   free,
+		KclRun:    run,
+	}, nil
+}
+
+func (m *KCLModule) Run(opts *RunOptions) (string, error) {
+	filenamePtr, filenameLen, err := copyStringToWasmMemory(m.Store, m.KclMalloc, m.Memory, opts.Filename)
+	if err != nil {
+		return "", err
+	}
+	defer func() {
+		err := freeMemory(m.Store, m.KclFree, filenamePtr, filenameLen)
+		if err != nil {
+			fmt.Println("Failed to free filename memory:", err)
+		}
+	}()
+
+	sourcePtr, sourceLen, err := copyStringToWasmMemory(m.Store, m.KclMalloc, m.Memory, opts.Source)
+	if err != nil {
+		return "", err
+	}
+	defer func() {
+		err := freeMemory(m.Store, m.KclFree, sourcePtr, sourceLen)
+		if err != nil {
+			fmt.Println("Failed to free source memory:", err)
+		}
+	}()
+
+	resultPtr, err := m.KclRun.Call(m.Store, filenamePtr, sourcePtr)
+	if err != nil {
+		return "", err
+	}
+
+	result, _, err := copyCStrFromWasmMemory(m.Store, m.Memory, resultPtr.(int32))
+	if err != nil {
+		return "", err
+	}
+	defer func() {
+		err := freeMemory(m.Store, m.KclFree, resultPtr.(int32), int32(len(result)))
+		if err != nil {
+			fmt.Println("Failed to free result memory:", err)
+		}
+	}()
+
+	return result, nil
+}

wasm/examples/go/pkg/module/utils.go

@@ -0,0 +1,45 @@
+package module
+
+import "github.com/bytecodealliance/wasmtime-go/v22"
+
+func copyStringToWasmMemory(
+	store *wasmtime.Store,
+	malloc *wasmtime.Func,
+	memory *wasmtime.Memory,
+	str string,
+) (int32, int32, error) {
+	bytes := []byte(str)
+	length := len(bytes)
+	ptr, err := malloc.Call(store, int32(length))
+	if err != nil {
+		return 0, 0, err
+	}
+	data := memory.UnsafeData(store)
+	idx := ptr.(int32)
+	copy(data[idx:(int(idx)+length)], bytes)
+	return idx, int32(length), nil
+}
+
+func copyCStrFromWasmMemory(
+	store *wasmtime.Store,
+	memory *wasmtime.Memory,
+	ptr int32,
+) (string, int32, error) {
+	data := memory.UnsafeData(store)
+	end := ptr
+	for data[end] != 0 {
+		end++
+	}
+	result := string(data[ptr:end])
+	return result, end + 1 - ptr, nil
+}
+
+func freeMemory(
+	store *wasmtime.Store,
+	free *wasmtime.Func,
+	ptr int32,
+	length int32,
+) error {
+	_, err := free.Call(store, ptr, length)
+	return err
+}