testsuite: added http server helper

Author: cmaglie

internal/integrationtest/http.go

@@ -0,0 +1,49 @@
+// This file is part of arduino-cli.
+//
+// Copyright 2022 ARDUINO SA (http://www.arduino.cc/)
+//
+// This software is released under the GNU General Public License version 3,
+// which covers the main part of arduino-cli.
+// The terms of this license can be found at:
+// https://www.gnu.org/licenses/gpl-3.0.en.html
+//
+// You can be released from the requirements of the above licenses by purchasing
+// a commercial license. Buying such a license is mandatory if you want to
+// modify or otherwise use the software for commercial activities involving the
+// Arduino software without disclosing the source code of your own applications.
+// To purchase a commercial license, send an email to license@arduino.cc.
+
+package integrationtest
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"testing"
+
+	"github.com/arduino/go-paths-helper"
+	"github.com/stretchr/testify/require"
+)
+
+// HTTPServeFile spawn an http server that serve a single file. The server
+// is started on the given port. The URL to the file and a cleanup function are returned.
+func HTTPServeFile(t *testing.T, port uint16, path *paths.Path) (*url.URL, func()) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/"+path.Base(), func(w http.ResponseWriter, r *http.Request) {
+		http.ServeFile(w, r, path.String())
+	})
+	server := &http.Server{
+		Addr:    fmt.Sprintf(":%d", port),
+		Handler: mux,
+	}
+
+	fileUrl, err := url.Parse(fmt.Sprintf("http://127.0.0.1:%d/%s", port, path.Base()))
+	require.NoError(t, err)
+
+	go func() {
+		err := server.ListenAndServe()
+		require.Equal(t, err, http.ErrServerClosed)
+	}()
+
+	return fileUrl, func() { server.Close() }
+}