feat: initial add for (Tiny)Go SDK

Signed-off-by: Radu Matei <radu.matei@fermyon.com>

.gitignore

@@ -3,3 +3,4 @@ target
 cache
 node_modules
 ignored-assets
+main.wasm

sdk/go/go.mod

@@ -0,0 +1,3 @@
+module github.com/fermyon/spin-sdk
+
+go 1.17

sdk/go/http.go

@@ -0,0 +1,17 @@
+package spin_http
+
+import (
+	"net/http"
+	"net/http/cgi"
+)
+
+// The entrypoint handler for a Spin HTTP component.
+//
+// This is currently handled using CGI to form the request and reponse,
+// but as Go implements support for the component model, the underlying
+// implementation of this function can change, but the exported signature
+// can continue to always be
+// `func Handler(h func(w http.ResponseWriter, r *http.Request)) error`.
+func Handler(h func(w http.ResponseWriter, r *http.Request)) error {
+	return cgi.Serve(http.HandlerFunc(h))
+}

templates/spin-http-tinygo/Makefile

@@ -0,0 +1,7 @@
+.PHONY: build
+build:
+	tinygo build -wasm-abi=generic -target=wasi -o main.wasm main.go
+
+. PHONY: serve
+serve:
+	RUST_LOG=spin=trace spin up --file spin.toml

templates/spin-http-tinygo/go.mod

@@ -0,0 +1,11 @@
+module github.com/fermyon/spin/templates/spin-http-tinygo
+
+go 1.17
+
+require (
+	github.com/fermyon/spin-sdk v0.0.0
+)
+
+replace (
+	github.com/fermyon/spin-sdk v0.0.0 => ../../sdk/go/
+)

templates/spin-http-tinygo/main.go

@@ -0,0 +1,14 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+
+	spin_http "github.com/fermyon/spin-sdk"
+)
+
+func main() {
+	spin_http.Handler(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintln(w, "Hello, Fermyon!")
+	})
+}

templates/spin-http-tinygo/spin.toml

@@ -0,0 +1,13 @@
+apiVersion = "0.1.0"
+authors = ["Fermyon Engineering <engineering@fermyon.com>"]
+description = "A simple Spin application written in (Tiny)Go."
+name = "spin-hello-world"
+trigger = { type = "http", base = "/" }
+version = "1.0.0"
+
+[[component]]
+id = "hello"
+source = "main.wasm"
+[component.trigger]
+route = "/hello"
+executor = { type = "wagi" }