Question

我对React Native还是很陌生，我试图弄清楚如何将前端连接到后端。我意识到我的文件夹结构可能设置得很奇怪，但是连接正常，我可以从数据库中获取数据，但是当我尝试发布时，它会引发500错误。我似乎无法弄清楚这是怎么回事。如果有人有见识，我将不胜感激。 post方法控制台将req.body和“我们在这里”记录在控制器文件中，但此后立即失败。

// index.js

require("dotenv").config();
const express = require("express");
const app = express();
const bodyParser = require("body-parser");
const morgan = require("morgan");
const { UserRoutes, TweetsRoutes } = require("./modules");
import dbConfig from "./config/db";

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(morgan("dev"));
// -----Database ----- \\
dbConfig(process.env.MONGO_DB_URL);

app.use((req, res, next) => {
  res.header("Access-Control-Allow-Origin", "*");
  res.header(
    "Access-Control-Allow-Headers",
    "Origin, X-Requested-With, Content-Type, Accept"
  );
  next();
});

app.use("/api", [UserRoutes, TweetsRoutes]);

// app.get("/", (req, res) => {
//   res.send("endpoint live");
// });

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => console.log(`Server listening on port ${PORT}`));

// db.js

const mongoose = require("mongoose");
export default mongoURL => {
  mongoose.Promise = global.Promise;
  mongoose.connect(
    mongoURL,
    { useNewUrlParser: true }
  );

  let db = mongoose.connection;

  db.once("open", () => console.log("Connected to the database"));
  db.on("error", console.error.bind(console, "Mongo connection error: "));
};

// tweetController.js

import Tweet from "./TweetsSchema";

module.exports = {
  createTweet: async (req, res, next) => {
    const createdTweet = req.body;
    console.log("req.body: ", req.body);

    try {
      console.log("Here we are");
      let tweet = await new Tweet.create(createdTweet);
      tweet.save();
      console.log("tweet: ", tweet);
      res.status(201).json(tweet);
    } catch (error) {
      res.status(500).json({
        error: true,
        message: "There was an error creating the tweet"
      });
    }
  },
  getAllTweets: async (req, res, next) => {
    const foundTweets = await Tweet.find({})
      .lean()
      .exec();
    res.status(200).json(foundTweets);
    next();
  }
};

// actions.js


export const postTweet = tweet => {
  let response = axios
     .post(
       `http://10.0.2.2:<PORT>/api/tweet`,
       { tweet },
       {
         headers: {
           "Content-Type": "application/json;charset=UTF-8",
           "Access-Control-Allow-Origin": "*"
         }
       }
     )
     .then(res => {
       return res.data;
     })
     .catch(error => {
       console.log(error);
     });
  return {
    type: POST_TWEET,
    payload: response
  };
};

Answer 1

问题是您混入了两个用于创建新文档的命令

不要像这样同时使用new和create：

let tweet = await new Tweet.create(createdTweet);

您应该只使用其中的一种：

let tweet = await Tweet.create(createdTweet);
tweet.save();

或者：

let tweet = new Tweet(createdTweet);
await tweet.save();

在React Native中发布到我的Mongo数据库的问题

1 个答案: