Making the module both TinyGo and Go friendly for compilation/testing…

…. Tweaking registration functions. (#3)

Co-authored-by: Phil Kedy <[email protected]>

README.md

@@ -1,7 +1,5 @@
 # waPC Guest Library for TinyGo
 
-**Note:** Consider this SDK experimental.  We have yet to put it through more advanced use cases than "hello world".
-
 This is the TinyGo implementation of the **waPC** standard for WebAssembly guest modules. It allows any waPC-compliant WebAssembly host to invoke to procedures inside a TinyGo compiled guest and similarly for the guest to invoke procedures exposed by the host.
 
 ## Example
@@ -15,7 +13,7 @@ import (
 )
 
 func main() {
-	wapc.Register(wapc.Functions{
+	wapc.RegisterFunctions(wapc.Functions{
 		"hello": hello,
 	})
 }
@@ -30,9 +28,8 @@ func hello(payload []byte) ([]byte, error) {
 tinygo build -o example/hello.wasm -target wasm -no-debug example/hello.go
 ```
 
-## Known limitations
+## Considerations
 
-* Only go up to 1.13 is supported by TinyGo
-* The `fmt` package requires `syscall/js.*` which are not imported by the waPC host
-* TinyGo has limited `reflect` package support, thus libraries like protobuf will likely not work
-* [No garbage collector](https://tinygo.org/compiler-internals/heap-allocation/) - memory allocation occurs in this library
+* It is recommended to use the latest versions Go and TinyGo
+* Avoid using the `fmt` package as it requires `syscall/js.*` which are not implemented by the waPC host libraries
+* TinyGo has limited `reflect` package support, thus generated Protobuf code will likely not work without some tweaking (But we have gotten it to work!)

example/hello.go

@@ -5,7 +5,7 @@ import (
 )
 
 func main() {
-	wapc.Register(wapc.Functions{
+	wapc.RegisterFunctions(wapc.Functions{
 		"hello": hello,
 	})
 }

go.mod

@@ -0,0 +1,3 @@
+module github.com/wapc/wapc-guest-tinygo
+
+go 1.15

imports.go

@@ -0,0 +1,25 @@
+// +build !purego,!appengine,!wasm
+
+package wapc
+
+func guestRequest(operationPtr uintptr, payloadPtr uintptr) {}
+
+func guestResponse(ptr uintptr, len uint32) {}
+
+func guestError(ptr uintptr, len uint32) {}
+
+func hostCall(
+	bindingPtr uintptr, bindingLen uint32,
+	namespacePtr uintptr, namespaceLen uint32,
+	operationPtr uintptr, operationLen uint32,
+	payloadPtr uintptr, payloadLen uint32) bool {
+	return true
+}
+
+func hostResponseLen() uint32 { return 0 }
+
+func hostResponse(ptr uintptr) {}
+
+func hostErrorLen() uint32 { return 0 }
+
+func hostError(ptr uintptr) {}

imports_wasm.go

@@ -0,0 +1,39 @@
+// +build wasm
+
+package wapc
+
+//go:wasm-module wapc
+//go:export __guest_request
+func guestRequest(operationPtr uintptr, payloadPtr uintptr)
+
+//go:wasm-module wapc
+//go:export __guest_response
+func guestResponse(ptr uintptr, len uint32)
+
+//go:wasm-module wapc
+//go:export __guest_error
+func guestError(ptr uintptr, len uint32)
+
+//go:wasm-module wapc
+//go:export __host_call
+func hostCall(
+	bindingPtr uintptr, bindingLen uint32,
+	namespacePtr uintptr, namespaceLen uint32,
+	operationPtr uintptr, operationLen uint32,
+	payloadPtr uintptr, payloadLen uint32) bool
+
+//go:wasm-module wapc
+//go:export __host_response_len
+func hostResponseLen() uint32
+
+//go:wasm-module wapc
+//go:export __host_response
+func hostResponse(ptr uintptr)
+
+//go:wasm-module wapc
+//go:export __host_error_len
+func hostErrorLen() uint32
+
+//go:wasm-module wapc
+//go:export __host_error
+func hostError(ptr uintptr)

wapc.go

@@ -5,42 +5,6 @@ import (
 	"unsafe"
 )
 
-//go:wasm-module wapc
-//go:export __guest_request
-func guestRequest(operationPtr uintptr, payloadPtr uintptr)
-
-//go:wasm-module wapc
-//go:export __guest_response
-func guestResponse(ptr uintptr, len uint32)
-
-//go:wasm-module wapc
-//go:export __guest_error
-func guestError(ptr uintptr, len uint32)
-
-//go:wasm-module wapc
-//go:export __host_call
-func hostCall(
-	bindingPtr uintptr, bindingLen uint32,
-	namespacePtr uintptr, namespaceLen uint32,
-	operationPtr uintptr, operationLen uint32,
-	payloadPtr uintptr, payloadLen uint32) bool
-
-//go:wasm-module wapc
-//go:export __host_response_len
-func hostResponseLen() uint32
-
-//go:wasm-module wapc
-//go:export __host_response
-func hostResponse(ptr uintptr)
-
-//go:wasm-module wapc
-//go:export __host_error_len
-func hostErrorLen() uint32
-
-//go:wasm-module wapc
-//go:export __host_error
-func hostError(ptr uintptr)
-
 type (
 	// Function is the function to register in your waPC module.
 	Function func(payload []byte) ([]byte, error)
@@ -58,14 +22,20 @@ var (
 	allFunctions = Functions{}
 )
 
-// Register adds functions by name to the registery.
+// RegisterFunctions adds functions by name to the registery.
 // This should be invoked in `main()`.
-func Register(functions Functions) {
+func RegisterFunctions(functions Functions) {
 	for name, fn := range functions {
 		allFunctions[name] = fn
 	}
 }
 
+// RegisterFunction adds a single function by name to the registery.
+// This should be invoked in `main()`.
+func RegisterFunction(name string, fn Function) {
+	allFunctions[name] = fn
+}
+
 //go:export __guest_call
 func guestCall(operationSize uint32, payloadSize uint32) bool {
 	operation := make([]byte, operationSize) // alloc