Express/Mongoose/Jest error: ECONNABORTED

Question

我有一个 API 内置的 Express，我正在用 Jest 对其进行测试。当我使用 Postman 进行测试时，API 工作正常，但是当我运行我的测试套件时，我通常在使用 .attach 上传文件时遇到 ECONNABORTED 错误(). （有时，它工作得很好。）我正在使用一套中间件来下载 URL 引用的图像数组，然后是通过表单上传传递到端点的任何图像。保存图像后，我使用第三个中间件调整图像大小并将它们保存在子目录中。由于该错误只发生在 Jest 中，似乎这就是错误所在，但我也不确定我是否正确处理了 Multer 的错误。

// endpoint.js

const storage = multer.diskStorage({
  destination: async (req, file, cb) => {
    // Check for product's existence
    if (product) {
      // Make the directory if necessary
      cb(null, /* location */)
    } else {
      cb(404, null)
    }
  },
  filename: async (req, file, cb) => {
    cb(
      null, /* location */}`
    )
  }
})

const upload = multer({ storage }).array("files")

router.post(
  "/:id",
  async (req, res, next) => {
    // Download images from URLs if provided
    next()
  },
  (req, res, next) => {
    upload(req, res, err => {
      // Handle errors (e.g. return res.status(404).json({ message: "Product not found" })
    })
    next()
  },
  async (req, res) => {
    // resize and save to subdirectory
  }
)

// endpoint.test.js

describe("/endpoint", () => {
  describe("POST", () => {
    it("saves uploaded images to the server", async () => {
      const response = await request(app)
        .post(`/endpoint/${id}`)
        .attach("files", "assets/img-test-1.jpg")
        .attach("files", "assets/img-test-2.jpg")
        .set("Content-Type", "multipart/form-data")

      expect(response.status).toEqual(201)
    }, 30000)

  ...

})

编辑：通过将 next() 调用移动到 Multer 处理程序中修复了原始错误。但是，现在发生了同样的错误，只是在不同的测试中。同样，错误仅在测试脚本运行ning 时发生；通过 Postman 拨打相同的电话时，我没有遇到任何问题。

// endpoint.js

let errors
router.post(
  "/:id",
  async (req, res, next) => {
    errors = []

    ...

    // This is the problematic call. If I explicitly set
    // product = null, the test runs normally
    const product = await Product.findById(req.params.id)
    if (!product) {
      errors.push({ status: 404, message: "Product not found" })
      return next()
    }

    ...

    return next()
  },
  // Several more middleware functions
})

// endpoint.test.js

...

beforeAll(done => {
  app.on("ready", async () => {
    const newProduct = await Product.create(product)
    id = newProduct._id
    done()
  })
})

...
describe("/api/bam/images", () => {
  describe("POST", () => {
    ...
    it("returns a 404 error if the associated product is not found", async () => {
      const response = await request(app)
        .post("/api/bam/images/000000000000000000000000")
        .attach("files", "assets/img-test-1.jpg")
        .attach("files", "assets/img-test-2.jpg")

      expect(response.status).toEqual(404)
    })
  })
})

Answer 1

我认为问题可能与在 multer 完成上传之前调用 next() 有关 - 尝试在上传回调中移动下一步：

(req, res, next) => {
    upload(req, res, err => {
      // Handle errors (e.g. return res.status(404).json({ message: "Product not found" 
      next()
      })
    })

  },

PT2：与编辑相关，如果问题似乎与那个 await 调用有关，那么可能会抛出错误但未被捕获 - 当您等待被拒绝的承诺时，它的行为就像正常投掷。扔在这里意味着 next 永远不会被调用：

    // This is the problematic call. If I explicitly set
    // product = null, the test runs normally
    try {
      const product = await Product.findById(req.params.id)
      if (!product) {
        errors.push({ status: 404, message: "Product not found" })
        return next()
      }
    } catch (err) {
      return next(err)
    }

Express/Mongoose/Jest error: ECONNABORTED

Express/Mongoose/Jest error: ECONNABORTED

mongoose

node.js

express

jestjs

multer