Add support for wasi-http in the wasm binding. (#3007)

Co-authored-by: Alessandro (Ale) Segala <[email protected]>

bindings/wasm/output.go

@@ -23,6 +23,8 @@ import (
 	"strings"
 	"sync/atomic"
 
+	"github.com/stealthrocket/wasi-go/imports/wasi_http"
+	"github.com/stealthrocket/wasi-go/imports/wasi_http/default_http"
 	"github.com/tetratelabs/wazero"
 	"github.com/tetratelabs/wazero/api"
 	"github.com/tetratelabs/wazero/imports/wasi_snapshot_preview1"
@@ -77,16 +79,27 @@ func (out *outputBinding) Init(ctx context.Context, metadata bindings.Metadata)
 		return fmt.Errorf("wasm: error compiling binary: %w", err)
 	}
 
-	switch detectImports(out.module.ImportedFunctions()) {
-	case modeWasiP1:
+	imports := detectImports(out.module.ImportedFunctions())
+
+	if _, found := imports[modeWasiP1]; found {
 		_, err = wasi_snapshot_preview1.Instantiate(ctx, out.runtime)
 	}
-
 	if err != nil {
 		_ = out.runtime.Close(context.Background())
-		return fmt.Errorf("wasm: error instantiating host functions: %w", err)
+		return fmt.Errorf("wasm: error instantiating host wasi functions: %w", err)
 	}
-	return
+	if _, found := imports[modeWasiHTTP]; found {
+		if out.meta.StrictSandbox {
+			_ = out.runtime.Close(context.Background())
+			return fmt.Errorf("can not instantiate wasi-http with strict sandbox")
+		}
+		err = wasi_http.Instantiate(ctx, out.runtime)
+	}
+	if err != nil {
+		_ = out.runtime.Close(context.Background())
+		return fmt.Errorf("wasm: error instantiating host wasi-http functions: %w", err)
+	}
+	return nil
 }
 
 func (out *outputBinding) Invoke(ctx context.Context, req *bindings.InvokeRequest) (*bindings.InvokeResponse, error) {
@@ -152,19 +165,23 @@ func (out *outputBinding) Close() error {
 const (
 	modeDefault importMode = iota
 	modeWasiP1
+	modeWasiHTTP
 )
 
 type importMode uint
 
-func detectImports(imports []api.FunctionDefinition) importMode {
+func detectImports(imports []api.FunctionDefinition) map[importMode]bool {
+	result := make(map[importMode]bool)
 	for _, f := range imports {
 		moduleName, _, _ := f.Import()
 		switch moduleName {
 		case wasi_snapshot_preview1.ModuleName:
-			return modeWasiP1
+			result[modeWasiP1] = true
+		case default_http.ModuleName:
+			result[modeWasiHTTP] = true
 		}
 	}
-	return modeDefault
+	return result
 }
 
 // GetComponentMetadata returns the metadata of the component.

bindings/wasm/output_test.go

@@ -18,6 +18,8 @@ import (
 	"context"
 	_ "embed"
 	"io"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -31,6 +33,7 @@ const (
 	urlArgsFile    = "file://testdata/args/main.wasm"
 	urlExampleFile = "file://testdata/example/main.wasm"
 	urlLoopFile    = "file://testdata/loop/main.wasm"
+	urlHTTPFile    = "file://testdata/http/main.wasm"
 )
 
 func Test_outputBinding_Init(t *testing.T) {
@@ -179,3 +182,89 @@ func Test_Invoke(t *testing.T) {
 		})
 	}
 }
+
+type handler struct{}
+
+func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path == "/unknown" {
+		w.WriteHeader(http.StatusNotFound)
+		w.Write([]byte("Not found"))
+		return
+	}
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(r.URL.Path))
+}
+
+func Test_InvokeHttp(t *testing.T) {
+	type testCase struct {
+		name         string
+		url          string
+		request      *bindings.InvokeRequest
+		ctx          context.Context
+		reqURL       string
+		expectedData string
+		expectedErr  string
+	}
+
+	s := httptest.NewServer(&handler{})
+	defer s.Close()
+
+	tests := []testCase{
+		{
+			name: "http",
+			url:  urlHTTPFile,
+			request: &bindings.InvokeRequest{
+				Operation: ExecuteOperation,
+			},
+			reqURL:       s.URL,
+			expectedData: "Status: 200\nBody: \n/\n",
+		},
+		{
+			name: "unknown",
+			url:  urlHTTPFile,
+			request: &bindings.InvokeRequest{
+				Operation: ExecuteOperation,
+			},
+			reqURL:       s.URL + "/unknown",
+			expectedData: "Status: 404\nBody: \nNot found\n",
+		},
+	}
+
+	for _, tt := range tests {
+		tc := tt
+		t.Run(tc.name, func(t *testing.T) {
+			l := logger.NewLogger(t.Name())
+			var buf bytes.Buffer
+			l.SetOutput(&buf)
+
+			meta := metadata.Base{Properties: map[string]string{"url": tc.url}}
+
+			output := NewWasmOutput(l)
+			defer output.(io.Closer).Close()
+
+			ctx := context.Background()
+
+			err := output.Init(ctx, bindings.Metadata{Base: meta})
+			require.NoError(t, err)
+
+			reqCtx := tc.ctx
+			if reqCtx == nil {
+				reqCtx = ctx
+			}
+
+			tc.request.Metadata = map[string]string{"args": tc.reqURL}
+
+			if tc.expectedErr == "" {
+				// execute twice to prove idempotency
+				for i := 0; i < 2; i++ {
+					resp, outputErr := output.Invoke(reqCtx, tc.request)
+					require.NoError(t, outputErr)
+					require.Equal(t, tc.expectedData, string(resp.Data))
+				}
+			} else {
+				_, err = output.Invoke(reqCtx, tc.request)
+				require.EqualError(t, err, tc.expectedErr)
+			}
+		})
+	}
+}

bindings/wasm/testdata/http/Makefile

@@ -0,0 +1,4 @@
+default: main.wasm
+
+main.wasm: main.go
+	tinygo build -target wasi -o main.wasm main.go

bindings/wasm/testdata/http/main.go

@@ -0,0 +1,35 @@
+package main
+
+// Building main.wasm:
+// go get github.com/dev-wasm/dev-wasm-go/http/client
+// tinygo build -target wasi -o main.wasm main.go
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+
+	wasiclient "github.com/dev-wasm/dev-wasm-go/http/client"
+)
+
+func printResponse(r *http.Response) {
+	fmt.Printf("Status: %d\n", r.StatusCode)
+	body, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		panic(err.Error())
+	}
+	fmt.Printf("Body: \n%s\n", body)
+}
+
+func main() {
+	client := http.Client{
+		Transport: wasiclient.WasiRoundTripper{},
+	}
+	res, err := client.Get(os.Args[1])
+	if err != nil {
+		panic(err.Error())
+	}
+	defer res.Body.Close()
+	printResponse(res)
+}

go.mod

@@ -99,6 +99,7 @@ require (
 	github.com/sendgrid/sendgrid-go v3.12.0+incompatible
 	github.com/sijms/go-ora/v2 v2.7.9
 	github.com/spf13/cast v1.5.1
+	github.com/stealthrocket/wasi-go v0.7.6-0.20230718231108-c3d30af59057
 	github.com/stretchr/testify v1.8.4
 	github.com/supplyon/gremcos v0.1.40
 	github.com/tencentcloud/tencentcloud-sdk-go/tencentcloud/common v1.0.608

go.sum

@@ -1861,6 +1861,9 @@ github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An
 github.com/spf13/viper v1.7.0/go.mod h1:8WkrPz2fc9jxqZNCJI/76HCieCp4Q8HaLFoCha5qpdg=
 github.com/spf13/viper v1.7.1/go.mod h1:8WkrPz2fc9jxqZNCJI/76HCieCp4Q8HaLFoCha5qpdg=
 github.com/spf13/viper v1.15.0 h1:js3yy885G8xwJa6iOISGFwd+qlUo5AvyXb7CiihdtiU=
+github.com/stealthrocket/wasi-go v0.7.6-0.20230718231108-c3d30af59057 h1:BaBBX206PM1+qF5WQx7Ug7mbKqzizBONDMv4ST5EVNg=
+github.com/stealthrocket/wasi-go v0.7.6-0.20230718231108-c3d30af59057/go.mod h1:PJ5oVs2E1ciOJnsTnav4nvTtEcJ4D1jUZAewS9pzuZg=
+github.com/stealthrocket/wazergo v0.19.1 h1:BPrITETPgSFwiytwmToO0MbUC/+RGC39JScz1JmmG6c=
 github.com/stoewer/go-strcase v1.2.0/go.mod h1:IBiWB2sKIp3wVVQ3Y035++gc+knqhUQag1KpM8ahLw8=
 github.com/streadway/amqp v0.0.0-20190404075320-75d898a42a94/go.mod h1:AZpEONHx3DKn8O/DFsRAY58/XVQiIPMTMB1SddzLXVw=
 github.com/streadway/amqp v0.0.0-20190827072141-edfb9018d271/go.mod h1:AZpEONHx3DKn8O/DFsRAY58/XVQiIPMTMB1SddzLXVw=