Validate Slack target URLs at creation time (closes #68)

internal/handlers/handlers_test.go

@@ -116,6 +116,52 @@ func TestHandleIndex_Authenticated(t *testing.T) {
 	)
 }
 
+func TestBuildSlackTargetConfig_AcceptsPublicURL(t *testing.T) {
+	t.Parallel()
+
+	var h *handlers.Handlers
+
+	app := newTestApp(t, &h)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	req := httptest.NewRequestWithContext(
+		context.Background(), http.MethodPost, "/", nil)
+	w := httptest.NewRecorder()
+
+	cfg, err := h.BuildSlackTargetConfigForTest(
+		w, req, "http://93.184.216.34/services/T00/B00/xxx",
+	)
+
+	require.NoError(t, err)
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, cfg, "webhookUrl")
+}
+
+func TestBuildSlackTargetConfig_RejectsReservedURL(t *testing.T) {
+	t.Parallel()
+
+	var h *handlers.Handlers
+
+	app := newTestApp(t, &h)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	req := httptest.NewRequestWithContext(
+		context.Background(), http.MethodPost, "/", nil)
+	w := httptest.NewRecorder()
+
+	cfg, err := h.BuildSlackTargetConfigForTest(
+		w, req, "http://169.254.169.254/latest/meta-data/",
+	)
+
+	require.Error(t, err)
+	assert.Empty(t, cfg)
+	assert.Equal(t, http.StatusBadRequest, w.Code)
+}
+
 func TestRenderTemplate(t *testing.T) {
 	t.Parallel()