tor: add GETINFO method to check liveness of onion service

tor/cmd_info_test.go

@@ -0,0 +1,87 @@
+package tor
+
+import (
+	"errors"
+	"io"
+	"syscall"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestCheckOnionServiceFailOnServiceNotCreated(t *testing.T) {
+	t.Parallel()
+
+	// Create a dummy tor controller.
+	c := &Controller{}
+
+	// Check that CheckOnionService returns an error when the service
+	// hasn't been created.
+	require.Equal(t, ErrServiceNotCreated, c.CheckOnionService())
+}
+
+func TestCheckOnionServiceSucceed(t *testing.T) {
+	t.Parallel()
+
+	// Create mock server and client connection.
+	proxy := createTestProxy(t)
+	defer proxy.cleanUp()
+	server := proxy.serverConn
+
+	// Assign a fake service ID to the controller.
+	c := &Controller{conn: proxy.clientConn, activeServiceID: "fakeID"}
+
+	// Test a successful response.
+	serverResp := "250-onions/current=fakeID\n250 OK\n"
+
+	// Let the server mocks a given response.
+	_, err := server.Write([]byte(serverResp))
+	require.NoError(t, err, "server failed to write")
+
+	// For a successful response, we expect no error.
+	require.NoError(t, c.CheckOnionService())
+}
+
+func TestCheckOnionServiceFailOnServiceIDNotMatch(t *testing.T) {
+	t.Parallel()
+
+	// Create mock server and client connection.
+	proxy := createTestProxy(t)
+	defer proxy.cleanUp()
+	server := proxy.serverConn
+
+	// Assign a fake service ID to the controller.
+	c := &Controller{conn: proxy.clientConn, activeServiceID: "fakeID"}
+
+	// Mock a response with a different serviceID.
+	serverResp := "250-onions/current=unmatchedID\n250 OK\n"
+
+	// Let the server mocks a given response.
+	_, err := server.Write([]byte(serverResp))
+	require.NoError(t, err, "server failed to write")
+
+	// Check the error returned from GetServiceInfo is expected.
+	require.ErrorIs(t, c.CheckOnionService(), ErrServiceIDUnmatch)
+}
+
+func TestCheckOnionServiceFailOnClosedConnection(t *testing.T) {
+	t.Parallel()
+
+	// Create mock server and client connection.
+	proxy := createTestProxy(t)
+	defer proxy.cleanUp()
+	server := proxy.serverConn
+
+	// Assign a fake service ID to the controller.
+	c := &Controller{conn: proxy.clientConn, activeServiceID: "fakeID"}
+
+	// Close the connection from the server side.
+	require.NoError(t, server.Close(), "server failed to close conn")
+
+	// Check the error returned from GetServiceInfo is expected.
+	err := c.CheckOnionService()
+	eof := errors.Is(err, io.EOF)
+	reset := errors.Is(err, syscall.ECONNRESET)
+	require.Truef(t, eof || reset,
+		"must of EOF or RESET error, instead got: %v", err)
+}