如何在 Heroku 上使用带有 Axios 和 Vue 的 Postgres 数据库？

Question

我使用 Vue 制作了一个 spa，并希望将其部署在 Heroku 上并使用 Postgres 配置一个数据库。

我设法让应用程序在 Heroku 上运行，并带有一个节点服务器。我添加了数据库和连接（在同一个文件中），它正在生产中工作。 但是我想使用 Axios 向数据库发出 HTTP 请求，并在部署之前在本地进行测试。这就是我卡住的地方。

我已将 DATABASE_URL 复制到 .env 中，但仍然无法访问数据库。当我将值打印到控制台时，它始终是未定义的。

我的 server.js：

const express = require("express");
const serveStatic = require("serve-static");
const path = require("path");
const port = process.env.PORT || 8080;

// Connection to the database
const { Client } = require('pg');
const client = new Client({
  connectionString: process.env.DATABASE_URL,
  ssl: {
    rejectUnauthorized: false
  }
});
client.connect();
client.query('SELECT table_schema,table_name FROM information_schema.tables;', (err, res) => {
  if (err) throw err;
  for (let row of res.rows) {
    console.log(JSON.stringify(row));
  }
  client.end();
});

//
const app = express();

//here we are configuring dist to serve app files
app.use("/", serveStatic(path.join(__dirname, "/dist")));

// this * route is to serve project on different page routes except root `/`
app.get(/.*/, function (req, res) {
  res.sendFile(path.join(__dirname, "/dist/index.html"));
});

app.listen(port);
console.log(`app is listening on port: ${port}`);

用户服务.js：

import axios from 'axios';

// the single Axios instance we use for calls
const apiClient = axios.create({
  //baseURL: 'http://localhost:5000',
  baseURL: process.env.DATABASE_URL, // with ssl?
  withCredentials: false, // this is the default
  headers: {
    Accept: 'application/json',
    'Content-Type': 'application/json',
  },
});

export default {
  /* with pagination */
  getUsers() {
    console.log(process.env.DATABASE_URL);
    return apiClient.get('/users');
  },
};

package.json:

{
  "name": "test-deploy-heroku",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "serve": "vue-cli-service serve",
    "build": "vue-cli-service build",
    "lint": "vue-cli-service lint",
    "start": "node server.js"
  },
  "dependencies": {
    "axios": "^0.21.1",
    "core-js": "^3.6.5",
    "dns": "^0.2.2",
    "express": "^4.17.1",
    "pg": "^8.5.1",
    "pg-native": "^3.0.0",
    "vue": "^2.6.11",
    "vue-router": "^3.2.0",
    "vuetify": "^2.4.0",
    "vuex": "^3.4.0"
  },
  "devDependencies": {
    "@vue/cli-plugin-babel": "~4.5.0",
    "@vue/cli-plugin-eslint": "~4.5.0",
    "@vue/cli-plugin-router": "~4.5.0",
    "@vue/cli-plugin-vuex": "~4.5.0",
    "@vue/cli-service": "~4.5.0",
    "@vue/eslint-config-prettier": "^6.0.0",
    "babel-eslint": "^10.1.0",
    "eslint": "^6.7.2",
    "eslint-plugin-prettier": "^3.3.1",
    "eslint-plugin-vue": "^6.2.2",
    "prettier": "^2.2.1",
    "sass": "^1.32.0",
    "sass-loader": "^10.0.0",
    "vue-cli-plugin-vuetify": "~2.3.1",
    "vue-template-compiler": "^2.6.11",
    "vuetify-loader": "^1.7.0"
  }
}

我将配置变量复制到我的本地 .env 文件中

heroku config:get CONFIG-VAR-NAME -s  >> .env

然后开始这个过程

heroku local

但是我仍然无法使用 axios 连接到数据库。

我找遍了，但没有找到答案。

Answer 1

您可能需要将 require('dotenv').config() 添加到 server.js 文件的顶部

if (process.env.NODE_ENV === 'development') require('dotenv').config()