gwasm

README

gwasm

Common utilities I find myself rewriting too often across Go WASM projects.

Documentation

Index

• type WASMHandler
  • func NewWASMHandler(wasmDir string, subHandler http.HandlerFunc) (*WASMHandler, error)
  • func (wsm *WASMHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)
  • func (wsm *WASMHandler) SetOutput(w io.Writer)

Types

type WASMHandler

type WASMHandler struct {
	// Compiler is the tool used to compile the WASM binary. Can be "go", "tinygo".
	Compiler string
	// IndexHTML is the html served to the user when loading the application. Should contain
	// the WASM bootstrap javascript to correctly load the WASM binary.
	IndexHTML string
	// WASMReload set to true recompiles the WASM application on every request.
	WASMReload bool
	// WASMDir points to the directory with the package/module with the Go WASM application.
	// If WASMDir is the empty string, it will serve the WASMApplication without compiling.
	WASMDir string
	// WASMApplication is the compiled WASM binary data as output by the go tool.
	WASMApplication []byte
	// Bootloader script. Filename can be found in a go installation by running
	//  out, err := exec.Command(wsm.Compiler, "env", "GOROOT").Output()
	//  if err != nil {
	//  	return nil, fmt.Errorf("%w: %s", err, string(out))
	//  }
	//  filename := filepath.Join(strings.TrimSpace(string(out)), "misc", "wasm", "wasm_exec.js")
	WASMExecContent []byte
	// contains filtered or unexported fields
}

WASMHandler serves a WASM application. Implements http.Handler interface.

func NewWASMHandler

func NewWASMHandler(wasmDir string, subHandler http.HandlerFunc) (*WASMHandler, error)

NewWASMHandler returns a handler which does basically the same thing as https://github.com/hajimehoshi/wasmserve.

Example of usage which does most of what `wasmserve` does:

wsm, err := gwasm.NewWASMHandler("app", nil)
if err != nil {
	log.Fatal(err)
}
wsm.WASMReload = true
wsm.SetOutput(os.Stdout)
http.Handle("/", wsm)
log.Fatal(http.ListenAndServe(":8080", nil))

func (*WASMHandler) ServeHTTP

func (wsm *WASMHandler) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP implements http.Handler interface. For use with http.Handle

func (*WASMHandler) SetOutput

func (wsm *WASMHandler) SetOutput(w io.Writer)

SetOutput sets logging write output to visualize compile-time errors and bad requests.