feat: remove strings dependency, optimizations (#23)

Author: nilslice

.github/workflows/ci.yml

@@ -47,3 +47,7 @@ jobs:
           echo $TEST | grep '"a": "this is var a"'
 
           extism call example/tiny_http.wasm --wasi http_get --github-token="$GITHUB_TOKEN" --allow-host "jsonplaceholder.typicode.com" | grep '"userId": 1'
+
+
+          # run all the tests
+          make test

Makefile

@@ -3,12 +3,12 @@ example:
 	tinygo build -o example/tiny_countvowels.wasm -target wasi ./example/countvowels
 	tinygo build -o example/tiny_http.wasm        -target wasi ./example/http
 
-	GOOS=wasip1 GOARCH=wasm go build -o example/std_countvowels.wasm ./example/countvowels
-	GOOS=wasip1 GOARCH=wasm go build -o example/std_http.wasm        ./example/http
+	GOOS=wasip1 GOARCH=wasm go build -tags std -o example/std_countvowels.wasm ./example/countvowels
+	GOOS=wasip1 GOARCH=wasm go build -tags std -o example/std_http.wasm        ./example/http
 
 test:
 	extism call example/tiny_countvowels.wasm count_vowels --wasi --input "this is a test" --set-config '{"thing": "1234"}'
 	extism call example/tiny_http.wasm        http_get     --wasi --log-level info --allow-host "jsonplaceholder.typicode.com"
 
-	extism call example/std_countvowels.wasm count_vowels --wasi --input "this is a test" --set-config '{"thing": "1234"}'
-	extism call example/std_http.wasm        http_get     --wasi --log-level info --allow-host "jsonplaceholder.typicode.com"
+	extism call example/std_countvowels.wasm _start     --wasi --input "this is a test" --set-config '{"thing": "1234"}'
+	extism call example/std_http.wasm        _start     --wasi --log-level info --allow-host "jsonplaceholder.typicode.com"

example/countvowels/std_main.go

@@ -0,0 +1,49 @@
+//go:build std
+// +build std
+
+package main
+
+import (
+	"strconv"
+
+	"github.com/extism/go-pdk"
+)
+
+// Currently, the standard Go compiler cannot export custom functions and is limited to exporting
+// `_start` via WASI. So, `main` functions should contain the plugin behavior, that the host will
+// invoke by explicitly calling `_start`.
+func main() {
+	countVowels()
+}
+
+func countVowels() int32 {
+	input := pdk.Input()
+
+	count := 0
+	for _, a := range input {
+		switch a {
+		case 'A', 'I', 'E', 'O', 'U', 'a', 'e', 'i', 'o', 'u':
+			count++
+		default:
+		}
+	}
+
+	// test some extra pdk functionality
+	if pdk.GetVar("a") == nil {
+		pdk.SetVar("a", []byte("this is var a"))
+	}
+	varA := pdk.GetVar("a")
+	thing, ok := pdk.GetConfig("thing")
+
+	if !ok {
+		thing = "<unset by host>"
+	}
+
+	output := `{"count": ` + strconv.Itoa(count) + `, "config": "` + thing + `", "a": "` + string(varA) + `"}`
+	mem := pdk.AllocateString(output)
+
+	// zero-copy output to host
+	pdk.OutputMemory(mem)
+
+	return 0
+}

example/countvowels/main.go renamed to example/countvowels/tiny_main.go

@@ -1,3 +1,6 @@
+//go:build !std
+// +build !std
+
 package main
 
 import (

example/http/std_main.go

@@ -0,0 +1,29 @@
+//go:build std
+// +build std
+
+package main
+
+import (
+	"github.com/extism/go-pdk"
+)
+
+// Currently, the standard Go compiler cannot export custom functions and is limited to exporting
+// `_start` via WASI. So, `main` functions should contain the plugin behavior, that the host will
+// invoke by explicitly calling `_start`.
+func main() {
+	httpGet()
+}
+
+func httpGet() int32 {
+	// create an HTTP Request (withuot relying on WASI), set headers as needed
+	req := pdk.NewHTTPRequest(pdk.MethodGet, "https://jsonplaceholder.typicode.com/todos/1")
+	req.SetHeader("some-name", "some-value")
+	req.SetHeader("another", "again")
+	// send the request, get response back (can check status on response via res.Status())
+	res := req.Send()
+
+	// zero-copy output to host
+	pdk.OutputMemory(res.Memory())
+
+	return 0
+}

example/http/main.go renamed to example/http/tiny_main.go

@@ -1,3 +1,6 @@
+//go:build !std
+// +build !std
+
 package main
 
 import (
@@ -7,7 +10,7 @@ import (
 //export http_get
 func httpGet() int32 {
 	// create an HTTP Request (withuot relying on WASI), set headers as needed
-	req := pdk.NewHTTPRequest("GET", "https://jsonplaceholder.typicode.com/todos/1")
+	req := pdk.NewHTTPRequest(pdk.MethodGet, "https://jsonplaceholder.typicode.com/todos/1")
 	req.SetHeader("some-name", "some-value")
 	req.SetHeader("another", "again")
 	// send the request, get response back (can check status on response via res.Status())

extism_pdk.go

@@ -3,7 +3,6 @@ package pdk
 import (
 	"encoding/binary"
 	"encoding/json"
-	"strings"
 )
 
 type Memory struct {
@@ -258,13 +257,54 @@ func (r HTTPResponse) Status() uint16 {
 	return r.status
 }
 
-func NewHTTPRequest(method string, url string) *HTTPRequest {
+type HTTPMethod int32
+
+const (
+	MethodGet HTTPMethod = iota
+	MethodHead
+	MethodPost
+	MethodPut
+	MethodPatch // RFC 5789
+	MethodDelete
+	MethodConnect
+	MethodOptions
+	MethodTrace
+)
+
+func (m HTTPMethod) String() string {
+	switch m {
+	case MethodGet:
+		return "GET"
+	case MethodHead:
+		return "HEAD"
+	case MethodPost:
+		return "POST"
+	case MethodPut:
+		return "PUT"
+	case MethodPatch:
+		return "PATCH"
+	case MethodDelete:
+		return "DELETE"
+	case MethodConnect:
+		return "CONNECT"
+	case MethodOptions:
+		return "OPTIONS"
+	case MethodTrace:
+		return "TRACE"
+	default:
+		return ""
+	}
+}
+
+func NewHTTPRequest(method HTTPMethod, url string) *HTTPRequest {
 	return &HTTPRequest{
 		meta: HTTPRequestMeta{
-			Url:    url,
-			Method: strings.ToUpper(method),
+			Url:     url,
+			Headers: nil,
+			Method:  method.String(),
 		},
-		body: nil}
+		body: nil,
+	}
 }
 
 func (r *HTTPRequest) SetHeader(key string, value string) *HTTPRequest {