add specs for crawler service

mocks/request.mock.js

@@ -0,0 +1,31 @@
+const sinon = jest.requireActual('sinon')
+
+let currentSpy = null
+
+const mockRequest = (options) => {
+  try {
+    const spy = currentSpy || sinon.spy()
+
+    console.info(`mock request ${JSON.stringify(options)}`)
+    spy(options)
+  } catch (err) {
+    console.trace(err)
+  }
+}
+
+const setRequestSpy = () => {
+  const spy = sinon.spy()
+
+  currentSpy = spy
+  return spy
+}
+
+const clearRequestSpy = () => {
+  currentSpy = null
+}
+
+module.exports = {
+  mockRequest,
+  setRequestSpy,
+  clearRequestSpy,
+}